Technical Field
[0001] The present disclosure relates to a construction machine driving device, and a construction
machine and a construction machine system including the construction machine driving
device.
Background Art
[0002] A construction machine includes a machine body and a work device capable of changing
an orientation with respect to the machine body. In a case where the construction
machine is, for example, a hydraulic excavator, the machine body is constituted by
a lower travelling body, and the work device includes an upper slewing body, a boom,
an arm, and a bucket. The construction machine performs various pieces of work at
a work site. An operator frequently performs a lever operation for adjusting an orientation
of a work device to a desired orientation according to content of work. However, it
is not easy for an unskilled person to efficiently perform such an operation. Therefore,
a technique in which a controller of a construction machine assists an operation by
an operator has been proposed.
[0003] Patent Literature 1 discloses a construction machine for assisting an operator so
that a work element can reliably reach a target value in an individual piece of work.
In this construction machine, in a case where pilot pressure is less than a maximum
value at a time point when a work element moves to a second predetermined position
before moving to a first predetermined position, a control device changes a value
of the pilot pressure output from operation device to the maximum value, and accelerates
the work element based on the changed maximum value. Further, the control device decelerates
and stops a work element using one deceleration pattern selected from a plurality
of deceleration patterns based on a speed of the work element detected by a speed
detector.
[0004] In the assist technique of Patent Literature 1 described above, pilot pressure is
changed to a maximum value regardless of a lever operation quantity that is the magnitude
of operation by an operator when a work element is accelerated, and a work element
is decelerated and stopped according to a preset deceleration pattern when a work
element is stopped. That is, in the assistance control of Patent Literature 1, since
an intention of an operator does not intervene in either acceleration or stop of a
work element, there is a problem that an operation technique of the operator is hardly
improved.
Citation List
Patent Literature
Summary of Invention
[0006] An object of the present disclosure is to provide a construction machine driving
device capable of assisting operation by an operator for adjusting an orientation
of a work device to a desired orientation while allowing intervention of an operator's
intention, and a construction machine and a construction machine system including
the construction machine driving device.
[0007] A construction machine driving device to be provided includes an operation device
to which an operation by an operator for moving a work device with respect to a machine
body is given, and a controller, in which the controller sets a target physical quantity
that is a target of a physical quantity related to an orientation of the work device,
calculates a current physical quantity that is a physical quantity related to an actual
orientation of the work device, calculates a physical quantity error that is an error
between the target physical quantity and the current physical quantity, calculates
an assistance operation value for assisting the operation of the operator, corrects
an operator operation value corresponding to the operation to an operator correction
value such that the operator correction value becomes smaller when the physical quantity
error is small as compared with when the physical quantity error is large, corrects
the assistance operation value to an assistance correction value such that the assistance
correction value becomes larger when the physical quantity error is small as compared
with when the physical quantity error is large, and controls the orientation of the
work device by using a total value obtained by adding the operator correction value
and the assistance correction value.
Brief Description of Drawings
[0008]
FIG. 1 is a side view illustrating an example of a construction machine including
a driving device according to an embodiment of the present disclosure.
FIG. 2 is a diagram illustrating a hydraulic circuit and a controller of the construction
machine.
FIG. 3 is an example of a map illustrating a relationship between a physical quantity
error and an assistance rate, the physical quantity error being an error between a
target physical quantity of a work device of the construction machine and a current
physical quantity of the work device.
FIG. 4 is an example of a block diagram illustrating a process of control by the controller.
FIG. 5 is a flowchart illustrating an example of arithmetic processing by the controller.
FIG. 6 is a side view for explaining operation of a work device in earth removal work
as an example of work performed by the construction machine.
FIG. 7 is a graph illustrating an example of a temporal change in a tip height of
a bucket and an assistance rate.
FIG. 8 is another example of a block diagram illustrating a process of control by
the controller.
FIG. 9 is still another example of a block diagram illustrating a process of control
by the controller.
FIG. 10 is a diagram illustrating an example of a display device of the driving device.
FIG. 11 is a diagram illustrating another example of the display device.
Description of Embodiments
[0009] Hereinafter, a construction machine driving device according to an embodiment of
the present disclosure and a construction machine including the construction machine
driving device will be described with reference to the drawings.
[First embodiment]
[0010] As illustrated in FIGS. 1 and 2, a construction machine 100 includes a lower travelling
body 1, an upper slewing body 2 supported by the lower travelling body 1 so as to
be slewable with respect to the lower travelling body 1 about a Z axis extending vertically,
an attachment 3 supported by the upper slewing body 2, a plurality of hydraulic actuators,
a plurality of hydraulic pumps, an orientation information acquisition unit, a plurality
of operation devices, a plurality of control valves, a plurality of proportional valves,
and a controller 50. The construction machine 100 according to the present embodiment
illustrated in FIG. 1 is a hydraulic excavator. The attachment 3 includes a boom 4,
an arm 5, and a tip attachment. The tip attachment is a bucket 6 in the specific example
illustrated in FIG. 1, but may be another tip attachment such as a fork, a grapple,
a breaker, a grinder (crusher), or the like. The driving device includes the plurality
of operation devices and the controller 50.
[0011] The lower travelling body 1 is an example of a machine body, and each of the upper
slewing body 2, the boom 4, the arm 5, and a tip attachment (for example, the bucket
6) is an example of a work device. Each of these work devices is a device operable
to change a relative orientation with respect to the lower travelling body 1.
[0012] The construction machine 100 can perform various pieces of work at a work site. The
various pieces of work include, for example, excavation work, earth and sand holding
and slewing work, earth removal work, and returning slewing work. The excavation work
is work of moving the bucket 6 along an excavation target such as the ground or banking
to excavate the excavation target and hold earth and sand in the bucket 6. The earth
and sand holding and slewing work is work of slewing the upper slewing body 2 while
holding excavated earth and sand in the bucket 6 to move the bucket 6 to the vicinity
of a cargo bed of a dump truck. The earth removal work is work of releasing earth
and sand held by the bucket 6 moved near a cargo bed from the bucket 6, and dropping
the earth and sand on the cargo bed of a dump truck to load the earth and sand on
the cargo bed. The returning slewing work is work of slewing the upper slewing body
2 and adjusting an orientation of the attachment 3 after earth removal work to move
the bucket 6 to the excavation target.
[0013] The lower travelling body 1 includes a pair of left and right travelling devices
for causing the construction machine 100 to travel, and a lower frame coupling these
travelling devices. The upper slewing body 2 includes an upper frame supported by
a lower frame so as to be slewable with respect to the lower frame, and a cabin and
a machine room supported by the upper frame. A driver's seat or the like on which
an operator sits is arranged in the cabin, and various devices constituting a hydraulic
circuit are arranged in the machine room.
[0014] The boom 4 has a base end portion supported by a front portion of an upper frame
of the upper slewing body 2 so that the boom 4 can rotate about a horizontal axis
(boom rotation axis) with respect to the upper slewing body 2, and a tip portion on
the opposite side of the base end portion. The arm 5 has a base end portion attached
to a tip portion of the boom 4 so that the arm 5 is rotatable about a horizontal axis
(arm rotation axis) with respect to the boom 4, and a tip portion on the opposite
side of the base end portion. The bucket 6 includes a base end portion attached to
a tip portion of the arm 5 so that the bucket 6 is rotatable about a horizontal axis
(bucket rotation axis) with respect to the arm 5, a housing portion which is a portion
capable of housing and holding earth and sand, and a tip of the bucket 6. In the present
embodiment, the tip of the bucket 6 is constituted by at least a part of a tooth for
excavation.
[0015] A plurality of hydraulic pumps include a main pump 21 and a pilot pump 22. The main
pump 21 and the pilot pump 22 are driven by, for example, an engine (not illustrated).
Each of the main pump 21 and the pilot pump 22 is driven by an engine to discharge
hydraulic oil. The pilot pump 22 is driven by an engine to supply pilot pressure to
each of a plurality of control valves.
[0016] A plurality of hydraulic actuators include a plurality of hydraulic cylinders and
a slewing motor 11. The plurality of hydraulic cylinders include at least one boom
cylinder 7 for moving the boom 4, an arm cylinder 8 for moving the arm 5, and a bucket
cylinder 9 for moving the bucket 6. Although only one of the main pump 21 is illustrated
in FIG. 2, the construction machine 100 may include a plurality of main pumps 21.
[0017] At least one of the boom cylinder 7 has one end portion connected to the upper slewing
body 2 and the other end connected to the boom 4. At least one of the boom cylinder
7 extends or contracts by receiving supply of hydraulic oil discharged from the main
pump 21, so as to rotate the boom 4 in a boom raising direction or a boom lowering
direction. The boom raising direction is a direction in which a tip portion of the
boom 4 moves away from the ground, and the boom lowering direction is a direction
in which the tip portion of the boom 4 approaches the ground.
[0018] The arm cylinder 8 has one end portion connected to the boom 4 and the other end
portion connected to the arm 5. The arm cylinder 8 extends or contracts by receiving
supply of hydraulic oil discharged from the main pump 21, so as to rotate the arm
5 in an arm pulling direction or an arm pushing direction. The arm pushing direction
is a direction in which a tip portion of the arm 5 moves away from the boom 4, and
the arm pulling direction is a direction in which the tip portion of the arm 5 approaches
the boom 4.
[0019] The bucket cylinder 9 has one end portion connected to the arm 5 and the other end
portion connected to the bucket 6 via a link member. The bucket cylinder 9 expands
or contracts by receiving supply of hydraulic oil discharged from the main pump 21,
so as to rotate the bucket 6 in a bucket pulling direction or a bucket pushing direction.
The bucket pulling direction is a direction in which a tip of the bucket 6 approaches
the lower travelling body 1, and the bucket pushing direction is a direction in which
the tip of the bucket 6 moves away from the lower travelling body 1.
[0020] The slewing motor 11 is a hydraulic motor that operates to slew the upper slewing
body 2 in a right direction or in a left direction with respect to the lower travelling
body 1 by receiving supply of hydraulic oil discharged from the main pump 21. The
slewing motor 11 includes an output part (not illustrated) that receives supply of
the hydraulic oil and rotates, and the output part transmits a driving force to the
upper slewing body 2 so as to slew the upper slewing body 2 in both left and right
directions. Specifically, the slewing motor 11 has a pair of ports, and by receiving
supply of hydraulic oil to one of the ports, the output part rotates in a direction
corresponding to the one of the ports and discharges hydraulic oil from the other
port.
[0021] The orientation information acquisition unit acquires orientation information that
is information on an orientation of a plurality of work devices including the upper
slewing body 2, the boom 4, the arm 5, and the bucket 6. The orientation information
acquisition unit inputs the acquired orientation information to the controller 50.
In the present embodiment, the orientation information acquisition unit includes a
boom orientation detector 31, an arm orientation detector 32, a bucket orientation
detector 33, and a slewing body orientation detector 34.
[0022] The boom orientation detector 31 detects boom orientation information that is information
on an orientation of the boom 4. The boom orientation detector 31 inputs a detection
signal corresponding to the detected boom orientation information to the controller
50. Specifically, the boom orientation detector 31 may be a boom angle sensor that
detects an angle (an example of boom orientation information) of the boom 4 with respect
to a preset reference. In this case, the reference may be, for example, the upper
slewing body 2, may be a horizontal plane, or may be a straight line or a plane perpendicular
to a slewing center axis (Z axis in FIG. 1). Further, the boom orientation detector
31 may be a cylinder stroke sensor that detects a cylinder length of the boom cylinder
7. The cylinder length of the boom cylinder 7 corresponds to an orientation of the
boom 4 with respect to the upper slewing body 2. The cylinder length of the boom cylinder
7 is an example of boom orientation information.
[0023] The arm orientation detector 32 detects arm orientation information that is information
on an orientation of the arm 5. The arm orientation detector 32 inputs a detection
signal corresponding to the detected arm orientation information to the controller
50. Specifically, the arm orientation detector 32 may be an arm angle sensor that
detects an angle (an example of arm orientation information) of the arm 5 with respect
to a preset reference. In this case, the reference may be, for example, the boom 4,
may be a horizontal plane, or may be a straight line or a plane perpendicular to a
slewing center axis (Z axis in FIG. 1). Further, the arm orientation detector 32 may
be a cylinder stroke sensor that detects a cylinder length of the arm cylinder 8.
The cylinder length of the arm cylinder 8 corresponds to an orientation of the arm
5 with respect to the boom 4. The cylinder length of the arm cylinder 8 is an example
of arm orientation information.
[0024] The bucket orientation detector 33 detects bucket orientation information that is
information on an orientation of the bucket 6. The bucket orientation detector 33
inputs a detection signal corresponding to the detected bucket orientation information
to the controller 50. Specifically, the bucket orientation detector 33 may be a bucket
angle sensor that detects an angle (an example of bucket orientation information)
of the bucket 6 with respect to a preset reference. In this case, the reference may
be, for example, the arm 5, may be a horizontal plane, or may be a straight line or
a plane perpendicular to a slewing center axis (Z axis in FIG. 1). Further, the bucket
orientation detector 33 may be a cylinder stroke sensor that detects a cylinder length
of the bucket cylinder 9. The cylinder length of the bucket cylinder 9 corresponds
to an orientation of the bucket 6 with respect to the arm 5. The cylinder length of
the bucket cylinder 9 is an example of bucket orientation information.
[0025] The slewing body orientation detector 34 detects slewing body orientation information
that is information on an orientation of the upper slewing body 2. The slewing body
orientation detector 34 inputs a detection signal corresponding to the detected slewing
body orientation information to the controller 50. Specifically, the slewing body
orientation detector 34 may be, for example, an inclination angle sensor that detects
an inclination angle (an example of slewing body orientation information) of the upper
slewing body 2 with respect to a horizontal plane, or may be a rotation angle sensor
that detects a rotation angle (an example of slewing body orientation information)
of the upper slewing body 2 with respect to the lower travelling body 1. Further,
the slewing body orientation detector 34 may include both the inclination angle sensor
and the rotation angle sensor.
[0026] Each of the boom angle sensor, the arm angle sensor, the bucket angle sensor, and
the rotation angle sensor may be, for example, a resolver, a rotary encoder, a potentiometer,
an inertial measurement unit (IMU), or another sensor. The inclination angle sensor
may be, for example, an IMU.
[0027] The controller 50 stores in advance size of each of a plurality of work devices according
to a model of the construction machine 100. Further, the controller 50 may store in
advance, for example, a relative positional relationship between a slewing center
axis and a boom rotation axis, a relative positional relationship between a boom rotation
axis, an arm rotation axis, a bucket rotation axis, and a corresponding work device,
and the like. By the above, the controller 50 can geometrically calculate an orientation
of each of a plurality of work devices including the upper slewing body 2, the boom
4, the arm 5, and the bucket 6 based on a detection signal input from each of the
detectors 31 to 34, and can calculate coordinates of a specific part SP that is a
part set in advance in any of a plurality of work devices. The specific part SP may
be set at a tip of the bucket 6, for example, as illustrated in FIG. 1.
[0028] As illustrated in FIG. 2, a plurality of operation devices include a boom operation
device 61, an arm operation device 62, a bucket operation device 63, and a slewing
operation device 64. Each of the operation devices 61 to 64 includes operation levers
61A to 64A that receive operation of an operator. Each of the operation devices 61
to 64 may include an electric operation device that inputs an operator operation value
(electric signal), which is an operation value corresponding to operation applied
to an operation lever by an operator, to the controller 50. FIG. 2 illustrates a circuit
configuration in a case where the operation devices 61 to 64 include an electric operation
device. Further, each of the operation devices 61 to 64 may include an operation device
(not illustrated) including a remote control valve.
[0029] A lever structure in which one operation lever functions as a plurality of operation
levers may be included. For example, a right operation lever arranged on the right
front side of a driver's seat on which an operator sits may function as the boom operation
lever 61A in a case of being operated in a front-rear direction, and may function
as the bucket operation lever 63A in a case of being operated in a left-right direction.
Further, a left operation lever arranged on the left front side of the driver's seat
may function as an arm operation lever 62A in a case of being operated in the front-rear
direction, and may function as a slewing operation lever 64A in a case of being operated
in the left-right direction. The lever structure may be configured such that a combination
functioning as a plurality of operation levers can be optionally changed by an operator's
instruction.
[0030] The operation lever 61A of the boom operation device 61 is configured to be able
to receive a boom raising operation that is an operation by an operator for moving
the boom 4 in the boom raising direction and a boom lowering operation that is an
operation by an operator for moving the boom 4 in the boom lowering direction. When
the boom raising operation or the boom lowering operation is given to the operation
lever 61A, the boom operation device 61 inputs an operator operation value (Lo) corresponding
to magnitude of the operation and a direction of the operation to the controller 50.
[0031] The operation lever 62A of the arm operation device 62 is configured to be able to
receive an arm pushing operation that is an operation by an operator for moving the
arm 5 in the arm pushing direction and an arm pulling operation that is an operation
by an operator for moving the arm 5 in the arm pulling direction. When the arm pushing
operation or the arm pulling operation is given to the operation lever 62A, the arm
operation device 62 inputs an operator operation value (Lo) corresponding to magnitude
of the operation and a direction of the operation to the controller 50.
[0032] The operation lever 63A of the bucket operation device 63 is configured to be able
to receive a bucket pulling operation that is an operation by an operator for moving
the bucket 6 in the bucket pulling direction and a bucket pushing operation that is
an operation by an operator for moving the bucket 6 in the bucket pushing direction.
When the bucket pulling operation or the bucket pushing operation is given to the
operation lever 63A, the bucket operation device 63 inputs an operator operation value
(Lo) corresponding to magnitude of the operation and a direction of the operation
to the controller 50.
[0033] The operation lever 64A of the slewing operation device 64 is configured to be able
to receive a right slewing operation which is an operation by an operator for slewing
the upper slewing body 2 in the right direction and a left slewing operation which
is an operation by an operator for slewing the upper slewing body 2 in the left direction.
When the right slewing operation or the left slewing operation is given to the operation
lever 64A, the slewing operation device 64 inputs an operator operation value (Lo)
corresponding to magnitude of the operation and a direction of the operation to the
controller 50.
[0034] A plurality of control valves include a boom control valve 41, an arm control valve
42, a bucket control valve 43, and a slewing control valve 44. Each of the plurality
of control valves has a pair of pilot ports.
[0035] The boom control valve 41 is interposed between the main pump 21 and the boom cylinder
7, and opens and closes to change a direction and a flow rate of hydraulic oil supplied
to the boom cylinder 7 according to pilot pressure supplied to a pilot port corresponding
to one of the boom raising operation and the boom lowering operation.
[0036] The arm control valve 42 is interposed between the main pump 21 and the arm cylinder
8, and opens and closes to change a direction and a flow rate of hydraulic oil supplied
to the arm cylinder 8 according to pilot pressure supplied to a pilot port corresponding
to one of the arm pushing operation and the arm pulling operation.
[0037] The bucket control valve 43 is interposed between the main pump 21 and the bucket
cylinder 9, and opens and closes to change a direction and a flow rate of hydraulic
oil supplied to the bucket cylinder 9 according to pilot pressure supplied to a pilot
port corresponding to one of the bucket pulling operation and the bucket pushing operation.
[0038] The slewing control valve 44 is interposed between the main pump 21 and the slewing
motor 11, and opens and closes to change a direction and a flow rate of hydraulic
oil supplied to the slewing motor 11 according to pilot pressure supplied to a pilot
port corresponding to one of the right slewing operation and the left slewing operation.
[0039] A plurality of proportional valves include a pair of boom electromagnetic proportional
valves 45 and 45, a pair of arm electromagnetic proportional valves 46 and 46, a pair
of bucket electromagnetic proportional valves 47 and 47, and a pair of slewing electromagnetic
proportional valves 48 and 48. Each of the plurality of proportional valves reduces
pressure of pilot oil (hydraulic oil) discharged from the pilot pump 22 in accordance
with a control command input from the controller 50, and opens and closes such that
pilot pressure that is the reduced pressure is supplied to a pilot port of a control
valve corresponding to the proportional valve. By the above, the control valve opens,
in a direction corresponding to a pilot port to which pilot pressure is supplied,
with a stroke corresponding to magnitude of the pilot pressure. As a result, hydraulic
oil from the main pump 21 is supplied to a hydraulic actuator corresponding to the
control valve at a flow rate corresponding to the stroke.
[0040] The controller 50 includes, for example, a computer including an arithmetic processing
device such as an MPU and a memory. The controller 50 includes an operation command
unit 51, a target physical quantity setting unit 52, a current physical quantity arithmetic
unit 53, a physical quantity error arithmetic unit 54, an assistance rate setting
unit 55, an assistance operation value arithmetic unit 56, an operator operation value
correction unit 57, an assistance operation value correction unit 58, and a work determination
unit 59. Each of the operation command unit 51, the target physical quantity setting
unit 52, the current physical quantity arithmetic unit 53, the physical quantity error
arithmetic unit 54, the assistance rate setting unit 55, the assistance operation
value arithmetic unit 56, the operator operation value correction unit 57, the assistance
operation value correction unit 58, and the work determination unit 59 is realized
by the arithmetic processing device executing a program.
[0041] The operation command unit 51 inputs the control command to each of a plurality of
proportional valves. Specifically, when the boom raising operation or the boom lowering
operation is given to the operation lever 61A of the boom operation device 61, the
operation command unit 51 inputs a control command to the boom electromagnetic proportional
valve 45 corresponding to the operation between the pair of the boom electromagnetic
proportional valves 45 and 45. When the arm pushing operation or the arm pulling operation
is given to the operation lever 62A of the arm operation device 62, the operation
command unit 51 inputs a control command to the arm electromagnetic proportional valve
46 corresponding to the operation between the pair of the arm electromagnetic proportional
valves 46 and 46. When the bucket pulling operation or the bucket pushing operation
is given to the operation lever 63A of the bucket operation device 63, the operation
command unit 51 inputs a control command to the bucket electromagnetic proportional
valve 47 corresponding to the operation between the pair of the bucket electromagnetic
proportional valves 47 and 47. When the right slewing operation or the left slewing
operation is given to the operation lever 64A of the slewing operation device 64,
the operation command unit 51 inputs a control command to the slewing electromagnetic
proportional valve 48 corresponding to the operation between the pair of the slewing
electromagnetic proportional valves 48 and 48.
[0042] More specifically, in a case where predetermined target work among a plurality of
pieces of work that can be performed by the construction machine 100 is performed,
as will be described later, the operation command unit 51 inputs a control command
calculated using an operator correction value (Lo') and an assistance correction value
(La') to a proportional valve corresponding to an operation performed in the target
work. The target work is work set in advance as a target of assistance by the controller
50 for an operation of an operator.
[0043] On the other hand, in a case where the target work is not performed among a plurality
of pieces of work, that is, in a case where non-target work that is work other than
the target work is performed, the operation command unit 51 inputs a command corresponding
to an operator operation value (Lo) input to the controller 50 from an operation device
operated in the non-target work among the plurality of operation devices 61 to 64
to a proportional valve corresponding to the operation as the control command.
[0044] The target physical quantity setting unit 52 sets a target physical quantity which
is a target of a physical quantity related to an orientation of at least one work
device. In the present embodiment, the physical quantity related to an orientation
of a work device is coordinates of a specific part, and the target physical quantity
is target coordinates of the specific part. In the present embodiment, the specific
part is a tip of the bucket 6. The target physical quantity setting unit 52 may set
target coordinates as described below, for example.
[0045] In the present embodiment, the construction machine 100 further includes a storage
switch 80 that can be operated by an operator. The storage switch 80 is arranged at
a position (for example, a position near a driver's seat) at which an operator can
operate in a cabin, for example. The storage switch 80 may be a button that can be
operated by an operator. Further, the storage switch 80 may be formed on a screen
of a display and may be a region that can be operated by an operator. An operator
arranges a tip of the bucket 6 at a desired position by operating at least one of
the operation levers 61A to 64A of the plurality of operation devices 61 to 64. In
a state where a tip of the bucket 6 is arranged at a desired position, an operator
performs an input operation (for example, button operation) on the storage switch
80. The target physical quantity setting unit 52 sets, as target coordinates, coordinates
at which a tip (specific part) of the bucket 6 is arranged at a time point when an
input operation is performed on the storage switch 80. A coordinate system serving
as a reference of target coordinates may be, for example, a coordinate system having
a preset position at a work site as the origin, a coordinate system having a preset
part in the construction machine 100 as the origin, or a coordinate system having
another position as the origin. Further, the coordinate system may be a three-dimensional
coordinate system or a two-dimensional coordinate system.
[0046] Note that the method of setting target coordinates is not limited to the above specific
example. For example, in a case where the construction machine 100 includes a camera
that acquires an image of a work site and a display that can display an image of the
work site (for example, a three-dimensional image) based on image data input from
the camera to the controller 50, when an operator designates a desired part in an
image displayed on the display (specifically, for example, when the operator touches
the desired part on a screen), the target physical quantity setting unit 52 may set
coordinates corresponding to the designated part as target coordinates. Further, the
target physical quantity setting unit 52 may set coordinates (a plurality of numerical
values) input by an operator as target coordinates.
[0047] The current physical quantity arithmetic unit 53 calculates a current physical quantity
which is a physical quantity related to an actual orientation of at least one work
device. In the present embodiment, the current physical quantity is actual coordinates
of a tip of the bucket 6, that is, current coordinates which are coordinates at that
time point. Therefore, the current physical quantity arithmetic unit 53 calculates
current coordinates which are coordinates of a tip (specific part) of the bucket 6.
The current physical quantity arithmetic unit 53 calculates current coordinates of
a tip of the bucket 6 based on orientation information input from the orientation
information acquisition unit. Specifically, the current physical quantity arithmetic
unit 53 may calculate an orientation of the boom 4, an orientation of the arm 5, and
an orientation of the bucket 6 based on, for example, boom orientation information,
arm orientation information, and bucket orientation information detected by the detectors
31 to 33, and calculate current coordinates of a tip of the bucket 6 based on these
orientations. Further, the current physical quantity arithmetic unit 53 may calculate
current coordinates of a tip of the bucket 6 in further consideration of slewing body
orientation information detected by the detector 34.
[0048] As illustrated in FIG. 1, an orientation of the boom 4 may be represented by a boom
angle θ1 which is an angle of the boom 4, an orientation of the arm 5 may be represented
by an arm angle θ2 which is an angle of the arm 5, and an orientation of the bucket
6 may be represented by a bucket angle Θ3 which is an angle of the bucket 6. The boom
angle θ1 may be, for example, an angle formed by a reference plane and a straight
line connecting a rotation center of the boom 4 at a base end portion of the boom
4 and a rotation center of the arm 5 at a base end portion of the arm 5.
[0049] The reference plane may be a horizontal plane or a plane orthogonal to a slewing
center axis (Z axis in FIG. 1). The arm angle θ2 may be an angle formed by a straight
line connecting the rotation center of the boom 4 and the rotation center of the arm
5 and a straight line connecting the rotation center of the arm 5 and a rotation center
of the bucket 6. The bucket angle Θ3 may be an angle formed by a straight line connecting
the rotation center of the arm 5 and the rotation center of the bucket 6 and a straight
line connecting the rotation center of the bucket 6 and a tip of the bucket 6.
[0050] The physical quantity error arithmetic unit 54 calculates a physical quantity error
that is an error between the target physical quantity and the current physical quantity.
In the present embodiment, the physical quantity error arithmetic unit 54 calculates
a coordinate error (e) that is an error between the target coordinates and the current
coordinates. Specifically, the physical quantity error arithmetic unit 54 calculates
the coordinate error (e) by using, for example, an equation "coordinate error (e)
= target coordinates - current coordinates". The coordinate error (e) calculated by
the above equation indicates a direction from current coordinates to target coordinates
and a distance from the current coordinates to the target coordinates.
[0051] The assistance rate setting unit 55 sets an assistance rate such that the assistance
rate has a larger value when the physical quantity error is small as compared with
when the physical quantity error is large. In the present embodiment, the assistance
rate setting unit 55 sets an assistance rate (r) such that the assistance rate (r)
has a larger value when the coordinate error (e) is small as compared with when the
coordinate error (e) is large. Specifically, the assistance rate setting unit 55 sets
the assistance rate (r) based on the coordinate error (e) calculated by the physical
quantity error arithmetic unit 54 and a map (graph) in which a relationship between
the coordinate error (e) and the assistance rate (r) is set in advance as illustrated
in FIG. 3, for example.
[0052] In the graph illustrated in FIG. 3, the horizontal axis represents magnitude of the
coordinate error (e), that is, a distance from current coordinates to target coordinates,
and the vertical axis represents the assistance rate (r). As illustrated in FIG. 3,
the assistance rate (r) is set to a maximum value ("1" in the specific example of
FIG. 3) in a small region where the coordinate error (e) is small, the assistance
rate (r) is set to a minimum value ("0" in the specific example of FIG. 3) in a large
region where the coordinate error (e) is large, and the assistance rate (r) is set
such that the assistance rate (r) becomes larger as the coordinate error (e) is smaller
in a middle region which is an intermediate region between the small region and the
large region. However, the map illustrated in FIG. 3 is an example of a map created
in advance for setting the assistance rate (r) such that the assistance rate (r) has
a larger value when the coordinate error (e) is small as compared with when the coordinate
error (e) is large, and the map representing a relationship between the coordinate
error (e) and the assistance rate (r) is not limited to the specific example illustrated
in FIG. 3. In the map, for example, at least a part of the middle region may be represented
by a curve, and at least one of the small region and the large region may be omitted.
Further, the maximum value of the assistance rate (r) may be a value larger than "1"
or a value smaller than "1", and the minimum value of the assistance rate (r) may
be a value larger than "0" or a value smaller than "0".
[0053] The assistance operation value arithmetic unit 56 calculates an assistance operation
value (La) which is an operation value for assisting operation of the operator. In
the present embodiment, the assistance operation value arithmetic unit 56 calculates
the assistance operation value (La) for assisting operation of the operator based
on the coordinate error (e). Specifically, the controller 50 stores in advance, for
example, Formula (1) described below for performing feedback control. For example,
as illustrated in FIG. 4, the assistance operation value arithmetic unit 56 (PID controller)
calculates the assistance operation value (La) by using Formula (1) described below
and the coordinate error (e). Note that, in Formula (1) described below, "u" is the
assistance operation value (La), "Kp", "Ki", and "Kd" are PID gains (a proportional
gain, an integral gain, and a derivative gain), and "e" is a coordinate error.
[Mathematical formula 1]

[0054] The assistance operation value (La) is an operation value for bringing the coordinate
error (e) close to zero, that is, an operation value for bringing a tip (specific
part) of the bucket 6 close to target coordinates. The controller 50 performs feedback
control using an assistance operation value (La) for bringing the coordinate error
(e) close to zero. For example, the assistance operation value (La) may be an operation
value that realizes at least one of bringing a direction in which a tip of the bucket
6 moves closer to target coordinates and decreasing a speed at which a tip of the
bucket 6 moves as magnitude (distance) of the coordinate error (e) is lowered. The
assistance operation value (La) may be an operation value that assists operation of
an operator so that a tip of the bucket 6 moves toward target coordinates. Further,
the assistance operation value (La) may be an operation value that makes a speed at
which a tip of the bucket 6 moves toward target coordinates large when the coordinate
error (e) is large, and makes a speed at which the tip of the bucket 6 moves toward
the target coordinates small when the coordinate error (e) is small.
[0055] The operator operation value correction unit 57 corrects the operator operation value
(Lo) to the operator correction value (Lo') such that the operator correction value
(Lo') becomes smaller when the physical quantity error is small as compared with when
the physical quantity error is large. In the present embodiment, the operator operation
value correction unit 57 corrects the operator operation value (Lo) to the operator
correction value (Lo') such that the operator correction value (Lo') becomes smaller
as the assistance rate (r) is larger. For example, the operator operation value correction
unit 57 may calculate the operator correction value (Lo') by multiplying the operator
operation value (Lo) by a value obtained by subtracting the assistance rate (r) from
a preset setting value (for example, "1"). Specifically, for example, the operator
operation value correction unit 57 calculates the operator correction value (Lo')
by using Formula (2) "Lo' = Lo × (1 - r)". In Formula (2), the assistance rate (r)
is a value (0 ≤ r ≤ 1) of zero or more and one or less.
[0056] Therefore, the operator correction value (Lo') decreases as the assistance rate (r)
increases.
[0057] The assistance operation value correction unit 58 corrects the assistance operation
value (La) to the assistance correction value (La') such that the assistance correction
value (La') becomes larger when the physical quantity error is small as compared with
when the physical quantity error is large. In the present embodiment, the assistance
operation value correction unit 58 corrects the assistance operation value (La) to
the assistance correction value (La') such that the assistance correction value (La')
becomes larger as the assistance rate (r) is larger. The assistance operation value
correction unit 58 calculates the assistance correction value (La') by, for example,
multiplying the assistance operation value (La) by the assistance rate (r). Specifically,
for example, the assistance operation value correction unit 58 calculates the assistance
correction value (La') by using Formula (3) "La' = La × r". In Formula (3), the assistance
rate (r) is a value (0 ≤ r ≤ 1) equal to or more than zero and equal to or less than
one like the one described above. Therefore, the assistance correction value (La')
becomes larger as the assistance rate (r) is larger.
[0058] As described above, in a case where target work is performed among a plurality of
pieces of work, the operation command unit 51 inputs a control command calculated
using the operator correction value (Lo') and the assistance correction value (La')
to a proportional valve corresponding to an operation performed in the target work.
Specifically, in a case where target work is performed, the operation command unit
51 outputs a total value obtained by adding the operator correction value (Lo') and
the assistance correction value (La') as a control command Y (Y = Lo × (1 - r) + La
× r) which is a final operation value. The output control command Y is input to a
proportional valve corresponding to at least one operation device among operation
devices operated in the target work.
[0059] The work determination unit 59 determines work performed by the construction machine
100. The work determination unit 59 can acquire a boom orientation, an arm orientation,
a bucket orientation, and a slewing body orientation based on a detection signal input
from the plurality of detectors 31 to 34 to the controller 50. For example, since
at least one of an orientation of the boom 4, an orientation of the arm 5, an orientation
of the bucket 6, and an orientation of the upper slewing body 2 is characteristically
changed temporally in each of excavation work, earth and sand holding and slewing
work, earth removal work, and returning slewing work, the work determination unit
59 can determine work of the construction machine 100 based on data of the temporal
change of at least one of the orientation of the boom 4, the orientation of the arm
5, the orientation of the bucket 6, and the orientation of the upper slewing body
2.
[0060] Specifically, for example, in a case where data of the temporal change satisfies
a predetermined condition related to excavation work, the work determination unit
59 determines that the construction machine 100 is performing the excavation work.
Similarly, the work determination unit 59 determines that the construction machine
100 is performing earth and sand holding and slewing work in a case where data of
the temporal change satisfies a predetermined condition related to the earth and sand
holding and slewing work, the work determination unit 59 determines that the construction
machine 100 is performing earth removal work in a case where data of the temporal
change satisfies a predetermined condition related to the earth removal work, and
the work determination unit 59 determines that the construction machine 100 is performing
returning slewing work in a case where data of the temporal change satisfies a predetermined
condition related to the returning slewing work.
[0061] The work determination unit 59 may determine work by the construction machine 100
based on the operator operation value (Lo) instead of or together with data of a temporal
change of at least one of an orientation of the boom 4, an orientation of the arm
5, an orientation of the bucket 6, and an orientation of the upper slewing body 2.
Further, the work determination unit 59 may determine work by the construction machine
100 based on a load applied to a work device instead of or together with data of a
temporal change of at least one of an orientation of the boom 4, an orientation of
the arm 5, an orientation of the bucket 6, and an orientation of the upper slewing
body 2. In this case, the work determination unit 59 may use, for example, a detection
result (detection signal) of a load sensor capable of detecting a load applied to
a work device or a load sensor attached to at least one of a plurality of movable
portions constituting a work device for determination of work of the construction
machine 100.
[0062] When the driving device of the construction machine 100 includes an input device
90 (see FIG. 2) that allows an operator to input a type of work, the work determination
unit 59 may determine work performed by the construction machine 100 based on work
content input by the operator.
[0063] Hereinafter, an example of arithmetic processing by the controller 50 will be described
with reference to a flowchart illustrated in FIG. 5. In a specific example below,
earth and sand loading work including a series of pieces of work is repeatedly performed
at a work site, the pieces of work including excavation work, earth and sand holding
and slewing work, earth removal work, and returning slewing work. Among these pieces
of work, the earth removal work is set as the target work described above, and the
excavation work, the earth and sand holding and slewing work, and the returning slewing
work are set as non-target work. The specific part is set to a tip of the bucket 6.
[0064] The target physical quantity setting unit 52 of the controller 50 determines whether
or not an input operation to the storage switch 80 (coordinate storage switch in the
present embodiment) is performed (Step S 1).
[0065] At a time point of starting earth and sand loading work, for example, as illustrated
in an upper diagram (A) in FIG. 6, an operator operates at least one of the operation
levers 61A to 64A of the operation devices 61 to 64 to move a tip of the bucket 6
to a desired position TP (position of a star). The position TP of the star is a target
position suitable for causing earth and sand held by the bucket 6 to fall from the
bucket 6 to a cargo bed of a dump truck in earth removal work. The operator presses
the storage switch 80 after stopping the tip of the bucket 6 at the desired position
TP (the position of the star).
[0066] When a signal indicating that the storage switch 80 is pressed is input to the controller
50, the target physical quantity setting unit 52 determines that an input operation
to the storage switch 80 is performed (YES in Step S1), and sets coordinates at which
the tip of the bucket 6 is located at that time as target coordinates (target physical
quantity) (Step S2). On the other hand, when determining that an input operation to
the storage switch 80 is not performed (NO in Step S1), the target physical quantity
setting unit 52 sets target coordinates (target physical quantity) to a default value
(Step S3). The default value may be coordinates previously set as target coordinates
and stored in a memory, or may be target coordinates set last time.
[0067] Next, the work determination unit 59 of the controller 50 determines whether or not
the earth removal work set as the target work is performed (Step S4). Based on a detection
signal input from the plurality of detectors 31 to 34 to the controller 50, for example,
in a case where data of a temporal change of an orientation of the arm 5 and an orientation
of the bucket 6 satisfies a predetermined condition related to the earth removal work,
the work determination unit 59 determines that the construction machine 100 is performing
the earth removal work (YES in Step S4). Specifically, this will be described below.
[0068] A work device at a time point at which earth and sand holding and slewing work performed
before the earth removal work is finished and the earth removal work is started is
arranged in, for example, an orientation (earth removal work starting orientation)
as illustrated in a second diagram (B) in FIG. 6. A third diagram (C) in FIG. 6 illustrates
an orientation of the work device at an intermediate stage of the earth removal work,
and a lower diagram (D) in FIG. 6 illustrates an orientation of the work device at
a time point at which the earth removal work is finished. As illustrated in the diagrams
(B) to (D), in the earth removal work, the arm pushing operation is given to the operation
lever 62A of the arm operation device 62 so that the arm 5 moves in the arm pushing
direction, and the bucket pushing operation is given to the operation lever 63A of
the bucket operation device 63 so that the bucket 6 moves in the bucket pushing direction.
That is, in the earth removal work, an orientation of the arm 5 and an orientation
of the bucket 6 characteristically change temporally as described above. Therefore,
a condition related to the earth removal work is set in advance to a condition for
which a characteristic temporal change in an orientation of the arm 5 and an orientation
of the bucket 6 as described above can be determined.
[0069] When the work determination unit 59 determines that the earth removal work is being
performed (YES in Step S4), the current physical quantity arithmetic unit 53 calculates
current coordinates which are coordinates of the tip of the bucket 6 at that time
point based on orientation information input from the orientation information acquisition
unit (detectors 31 to 34), and the physical quantity error arithmetic unit 54 calculates
the coordinate error (e) by using, for example, the above formula (coordinate error
(e) = target coordinates - current coordinates) (Step S5).
[0070] Next, the assistance rate setting unit 55 sets the assistance rate (r) based on,
for example, the map illustrated in FIG. 3 and the coordinate error (e) calculated
by the physical quantity error arithmetic unit 54 (Step S6).
[0071] Next, the operator operation value (Lo) at that time point is input to the controller
50. Specifically, when the arm pushing operation is given to the operation lever 62A,
the arm operation device 62 inputs the operator operation value (Lo), which is an
electric signal corresponding to magnitude of the arm pushing operation, to the controller
50, and when the bucket pushing operation is given to the operation lever 63A, the
bucket operation device 63 inputs the operator operation value (Lo), which is an electric
signal corresponding to magnitude of the bucket pushing operation, to the controller
50.
[0072] Further, the assistance operation value arithmetic unit 56 (PID controller) calculates
the assistance operation value (La) for assisting the bucket pushing operation by
using Formula (1) described above and the coordinate error (e).
[0073] The operator operation value correction unit 57 calculates the operator correction
value (Lo') by using Formula (2) described above, the operator operation value (Lo)
in the bucket pushing operation, and the assistance rate (r).
[0074] The assistance operation value correction unit 58 calculates the assistance correction
value (La') by using Formula (3) described above, the assistance operation value (La)
in the bucket pushing operation, and the assistance rate (r).
[0075] Regarding the bucket pushing operation, the operation command unit 51 outputs a total
value obtained by adding the operator correction value (Lo') and the assistance correction
value (La') as the control command Y (Y = Lo × (1 - r) + La × r) which is a final
operation value (Step S7). The output control command Y is input to the proportional
valve 47 corresponding to the bucket pushing operation.
[0076] On the other hand, when the work determination unit 59 determines that the earth
removal work is not being performed (NO in Step S4), the operation command unit 51
outputs the operator operation value (Lo) corresponding to an operation input from
at least one of the plurality of operation devices 61 to 64 as a control command which
is a final operation value (Step S8).
[0077] As described above, in this construction machine, the controller 50 controls an orientation
of at least one work device by using a total value obtained by adding the operator
correction value (Lo'), which is corrected to become a small value when the coordinate
error (e) is small as compared with when the coordinate error (e) is large, and the
assistance correction value (La'), which is corrected to become a large value when
the coordinate error (e) is small as compared with when the coordinate error (e) is
large. That is, the controller 50 performs feedback control using the assistance operation
value (La) for bringing the coordinate error (e) close to zero as illustrated in FIG.
4, and repeatedly performs arithmetic processing as illustrated in Steps S1 to S8
of the flowchart of FIG. 5. This makes it possible to assist operator's operation
for adjusting an orientation of at least one work device to a desired orientation
while allowing intervention of an operator's intention.
[0078] The controller 50 sets the assistance rate (r) that is large when the coordinate
error (e) is small as compared with when the coordinate error (e) is large, calculates
the assistance correction value (La') by multiplying the assistance operation value
(La) by the assistance rate (r), and calculates the operator correction value (Lo')
by multiplying the operator operation value (Lo) by a value obtained by subtracting
the assistance rate (r) from "1" that is a preset setting value. Therefore, as the
coordinate error (e) becomes smaller, that is, as a tip of the bucket 6 approaches
target coordinates, the operator correction value (Lo') can be continuously decreased
and the assistance correction value (La') can be continuously increased. This enables
smooth transition from a state in which operation by an operator is mainly performed
to a state in which assist by the controller 50 is mainly performed in a process in
which a tip of the bucket 6 approaches target coordinates.
[Second embodiment]
[0079] In the first embodiment, a physical quantity related to an orientation of a work
device is coordinates of a tip (specific portion) of the bucket 6, but in a second
embodiment, the physical quantity is a cylinder length detected by the stroke sensor
(an example of the orientation information acquisition unit). In the second embodiment,
a target physical quantity is a target cylinder length, and a current physical quantity
is an actual cylinder length (current cylinder length) detected by the stroke sensor.
A physical quantity error is a length error that is an error between a target cylinder
length and a current cylinder length.
[0080] In the second embodiment, the boom orientation detector 31 is a cylinder stroke sensor
that detects a cylinder length of the boom cylinder 7, the arm orientation detector
32 is a cylinder stroke sensor that detects a cylinder length of the arm cylinder
8, and the bucket orientation detector 33 is a cylinder stroke sensor that detects
a cylinder length of the bucket cylinder 9.
[0081] In the second embodiment, an operator arranges the boom 4, the arm 5, and the bucket
6 in a desired orientation by operating at least one of the operation levers 61A to
64A of the plurality of operation devices 61 to 64. The desired orientation varies
depending on target work.
[0082] Similarly to the first embodiment, the controller 50 of the driving device according
to the second embodiment may perform arithmetic processing along the flowchart illustrated
in FIG. 5, for example. Hereinafter, an example of arithmetic processing by the controller
50 according to the second embodiment will be described with reference to the flowchart
illustrated in FIG. 5. Also in a specific example below, target work is set to earth
removal work, and excavation work, earth and sand holding and slewing work, and returning
slewing work are set to non-target work.
[0083] The target physical quantity setting unit 52 of the controller 50 determines whether
or not an input operation to the storage switch 80 is performed (Step S1).
[0084] At a time point of starting earth and sand loading work, an operator operates at
least one of the operation levers 61A to 64A of the operation devices 61 to 64 to
arrange the arm 5 and the bucket 6 in a desired orientation as illustrated in an upper
diagram (A) in FIG. 6, for example, and, in this state, presses the storage switch
80.
[0085] When a signal indicating that the storage switch 80 is pressed is input to the controller
50, the target physical quantity setting unit 52 determines that input operation to
the storage switch 80 is performed (YES in Step S1), sets a cylinder length of the
arm cylinder 8 at that time point to a target cylinder length (first target cylinder
length), and sets a cylinder length of the bucket cylinder 9 at that time point to
a target cylinder length (second target cylinder length) (Step S2). On the other hand,
when determining that an input operation to the storage switch 80 is not performed
(NO in Step S1), the target physical quantity setting unit 52 sets a target cylinder
length to a default value (Step S3). The default value may be a value set in advance
as the first target cylinder length and the second target cylinder length and stored
in a memory, or may be the first target cylinder length and the second target cylinder
length set last time.
[0086] Next, the work determination unit 59 of the controller 50 determines whether earth
removal work is being performed (Step S4). Based on a detection signal input from
the plurality of detectors 31 to 34 to the controller 50, for example, in a case where
data of a temporal change of an orientation of the arm 5 and an orientation of the
bucket 6 satisfies a predetermined condition related to the earth removal work, the
work determination unit 59 determines that the construction machine 100 is performing
the earth removal work (YES in Step S4).
[0087] When the work determination unit 59 determines that the earth removal work is being
performed (YES in Step S4), the current physical quantity arithmetic unit 53 calculates
a current cylinder length (first current cylinder length) which is a cylinder length
of the arm cylinder 8 at that time point based on a detection signal input from the
arm orientation detector 32, and calculates a current cylinder length (second current
cylinder length) which is a cylinder length of the bucket cylinder 9 at that time
point based on a detection signal input from the bucket orientation detector 33. Then,
the physical quantity error arithmetic unit 54 calculates the first length error (e)
related to an orientation of the arm 5 by using, for example, a formula (first length
error = first target cylinder length - first current cylinder length), and calculates
the second length error (e) related to an orientation of the bucket 6 by using, for
example, a formula (second length error = second target cylinder length - second current
cylinder length) (Step S5).
[0088] The controller 50 stores in advance a map (arm map), for example, as illustrated
in FIG. 3, set in advance to control an orientation of the arm 5, and stores in advance
a map (bucket map), for example, as illustrated in FIG. 3, set in advance to control
an orientation of the bucket 6. These two maps are individually set in advance so
that each of the arm 5 and the bucket 6 performs appropriate operation in the earth
removal work. In the second embodiment, in the graph illustrated in FIG. 3, the horizontal
axis represents a length error (first length error or second length error), and the
vertical axis represents the assistance rate (r).
[0089] Next, the assistance rate setting unit 55 sets the first assistance rate (r) which
is an assistance rate for the arm 5 based on the arm map and the first length error
(e) calculated by the physical quantity error arithmetic unit 54, and sets the second
assistance rate (r) which is an assistance rate for the bucket 6 based on the bucket
map and the second length error (e) calculated by the physical quantity error arithmetic
unit 54 (Step S6).
[0090] Next, the operator operation value (Lo) at that time point is input to the controller
50. Specifically, when the arm pushing operation is given to the operation lever 62A,
the arm operation device 62 inputs an operator operation value (first operator operation
value (Lo)), which is an electric signal corresponding to magnitude of the arm pushing
operation, to the controller 50. When the bucket pushing operation is given to the
operation lever 63A, the bucket operation device 63 inputs an operator operation value
(second operator operation value (Lo)), which is an electric signal corresponding
to magnitude of the bucket pushing operation, to the controller 50.
[0091] The controller 50 stores in advance, for example, a formula (arm arithmetic expression)
as shown in Formula (1) described above, which is set in advance for feedback control
of an orientation of the arm 5, and stores in advance, for example, a formula (bucket
arithmetic expression) as shown in Formula (1) described above, which is set in advance
for feedback control of an orientation of the bucket 6. These two formulas are individually
set in advance so that each of the arm 5 and the bucket 6 performs appropriate operation
in the earth removal work.
[0092] The assistance operation value arithmetic unit 56 (PID controller) calculates the
first assistance operation value (La), which is an assistance operation value for
assisting the arm pushing operation, by using the arm arithmetic expression and the
first length error (e). Similarly, the assistance operation value arithmetic unit
56 (PID controller) calculates the second assistance operation value (La), which is
an assistance operation value for assisting the bucket pushing operation, by using
the bucket arithmetic expression and the second length error (e).
[0093] The operator operation value correction unit 57 calculates the first operator correction
value (Lo') by using Formula (2) described above, the first operator operation value
(Lo) in the arm pushing operation, and the first assistance rate (r), and calculates
the second operator correction value (Lo') by using Formula (2) described above, the
second operator operation value (Lo) in the bucket pushing operation, and the second
assistance rate (r).
[0094] The assistance operation value correction unit 58 calculates the first assistance
correction value (La') by using Formula (3) described above, the first assistance
operation value (La) in the arm pushing operation, and the first assistance rate (r),
and calculates the second assistance correction value (La') by using Formula (3) described
above, the second assistance operation value (La) in the bucket pushing operation,
and the second assistance rate (r).
[0095] Regarding the arm pushing operation, the operation command unit 51 outputs a first
total value that is a total value obtained by adding the first operator correction
value (Lo') and the first assistance correction value (La') as the first control command
Y (Y = Lo × (1 - r) + La × r) that is a final operation value. Further, regarding
the bucket pushing operation, the operation command unit 51 outputs a second total
value that is a total value obtained by adding the second operator correction value
(Lo') and the second assistance correction value (La') as the second control command
Y (Y = Lo × (1 - r) + La × r) which is a final operation value (Step S7). The output
first control command Y is input to the proportional valve 46 corresponding to the
arm pushing operation, and the output second control command Y is input to the proportional
valve 47 corresponding to the bucket pushing operation.
[0096] On the other hand, when the work determination unit 59 determines that the earth
removal work is not being performed (NO in Step S4), the operation command unit 51
outputs the operator operation value (Lo) corresponding to an operation input from
at least one of the plurality of operation devices 61 to 64 as a control command which
is a final operation value (Step S8).
[0097] As described above, the controller 50 performs the feedback control using the assistance
operation value (La) for bringing the length error (e) close to zero as illustrated
in FIG. 4 for each of the arm 5 and the bucket 6, and repeatedly performs the arithmetic
processing as illustrated in Steps S1 to S8 of the flowchart of FIG. 5 for each of
the arm 5 and the bucket 6. This makes it possible to assist operator's operation
for adjusting an orientation of the arm 5 and an orientation of the bucket 6 to a
desired orientation while allowing intervention of an operator's intention.
[Third embodiment]
[0098] In the driving device according to the above embodiment, the target work is the earth
removal work, but the driving device according to the present disclosure is not limited
to that in the above embodiment. The target work may be, for example, the returning
slewing work. In this case, the specific part is, for example, a tip of the bucket
6, the physical quantity related to an orientation of a work device is a height of
the tip of the bucket 6, the target physical quantity is, for example, a target height
(excavation start height) of the tip of the bucket 6, the current physical quantity
is, for example, a current height that is an actual height of the tip of the bucket
6, and the physical quantity error is a height error that is an error between the
target height (excavation start height) and the current height (for example, a distance
between the tip of the bucket 6 and a working surface). The excavation start height
and the current height may have, for example, a value based on the ground, or may
have a value based on a position below or above the ground. FIG. 7 is a graph illustrating
an example of a temporal change in a tip height of a bucket and an assistance rate
in this third embodiment, and FIG. 8 is an example of a block diagram illustrating
a process of control by the controller 50 in the third embodiment.
[0099] In the third embodiment, an operator arranges a tip of the bucket 6 at a desired
position by operating at least one of the operation levers 61A to 64A of the plurality
of operation devices 61 to 64. The desired position is, for example, a position of
the tip of the bucket 6 when excavation is started. When an operator performs an input
operation on the storage switch 80 in a state where the tip of the bucket 6 is arranged
at the desired position, the target physical quantity setting unit 52 sets a height
at which the tip of the bucket 6 is arranged at that time point as an excavation start
height (target height).
[0100] The current physical quantity arithmetic unit 53 calculates a current height (attachment
tip height) of the tip of the bucket 6 based on orientation information input from
the orientation information acquisition unit. For example, the current physical quantity
arithmetic unit 53 may calculate the current height based on the boom angle 01, the
arm angle θ2, and the bucket angle θ3 detected by the detectors 31 to 33, and an inclination
angle of the upper slewing body 2 with respect to the horizontal plane detected by
the slewing body orientation detector 34. Specifically, for example, when the ground
on which the lower travelling body 1 is arranged and the ground located below the
bucket 6 are assumed to be included in the same plane, the current physical quantity
arithmetic unit 53 can geometrically calculate a height of the tip of the bucket 6
from the ground based on a detection signal input from the detectors 31 to 34.
[0101] The physical quantity error arithmetic unit 54 calculates the height error, which
is an error between the excavation start height and the current height, by using,
for example, a formula "height error = excavation start height - current height".
[0102] The assistance rate setting unit 55 sets the assistance rate (r) such that the assistance
rate (r) has a larger value when the height error is small as compared with when the
height error is large. Specifically, the assistance rate setting unit 55 sets the
assistance rate (r) based on a height error calculated by the physical quantity error
arithmetic unit 54 and a map in which a relationship between the height error (e)
and the assistance rate (r) is set in advance as illustrated in FIG. 8, for example.
[0103] The assistance operation value arithmetic unit 56 calculates the assistance operation
value (La) which is for assisting operation of the operator. Specifically, in the
third embodiment, the assistance operation value arithmetic unit 56 calculates the
assistance operation value (La) which is an operation value for bringing an angular
error, which is an error between a target bucket angle and the actual bucket angle
θ3, close to zero.
[0104] In FIG. 1, an angle θ4 is an arm to ground angle that is an angle of the arm 5 with
respect to the ground, and an angle θ5 is a bucket to ground angle that is an angle
of the bucket 6 with respect to the ground. For example, as illustrated in FIG. 1,
the arm to ground angle θ4 may be an angle between a straight line connecting a rotation
center of the arm 5 with respect to the boom 4 and a rotation center of the bucket
6 with respect to the arm 5 and the ground. For example, as illustrated in FIG. 1,
the bucket to ground angle θ5 may be an angle between a straight line connecting a
rotation center of the bucket 6 with respect to the arm 5 and a tip of the bucket
6 and the ground.
[0105] The assistance operation value arithmetic unit 56 sets a target bucket angle based
on, for example, a map in which a relationship between the arm to ground angle θ4
and a target angle (target bucket angle) of the bucket 6 is set in advance as in the
graph drawn at the left end of FIG. 8 and the actual arm to ground angle θ4 at that
time. Next, the assistance operation value arithmetic unit 56 (PID controller) calculates
the assistance operation value (La) by using, for example, Formula (1) described above
and the angular error.
[0106] The operator operation value correction unit 57 calculates the operator correction
value (Lo') by using Formula (2) "Lo' = Lo × (1 - r)" similar to the one described
above. The calculated operator correction value (Lo') becomes smaller as the assistance
rate (r) is larger.
[0107] The assistance operation value correction unit 58 calculates the assistance correction
value (La') by using Formula (3) "La' = La × r" similar to the one described above.
The calculated assistance correction value (La') becomes larger as the assistance
rate (r) is larger.
[0108] In a case where target work (returning slewing work in the third embodiment) is performed,
the operation command unit 51 outputs a total value obtained by adding the operator
correction value (Lo') and the assistance correction value (La') as the control command
Y (Y = Lo × (1 - r) + La × r) which is a final operation value. The output control
command Y is input to a proportional valve corresponding to at least one operation
device among operation devices operated in the returning slewing work.
[0109] In the third embodiment, an assistance rate is set using a height error that is an
error between an excavation start height of the bucket 6 and a current height of a
tip of the bucket 6. Therefore, when a height error is large, it is possible to allow
significant intervention of an operator's intention. On the other hand, when the height
error is small, that is, when a tip of the bucket 6 approaches an excavation start
height (target height) and fine adjustment of an orientation of a work device is performed,
intervention of an operator's intention can be made less than that when the height
error is large, and the tip of the bucket 6 can be easily adjusted to the excavation
start height with assistance of the controller 50. By the above, it is possible to
achieve both intervention of an operator's intention and easy adjustment of an orientation
of a work device.
[0110] Further, in the third embodiment, the assistance operation value (La) is calculated
using an angular error that is an error between a target bucket angle and the actual
bucket angle Θ3. The assistance operation value (La) is an operation value calculated
using, for example, Formula (1) described above in order to bring the angular error
close to zero. Therefore, in the third embodiment, the controller 50 performs feedback
control using the assistance operation value (La) for bringing the angular error close
to zero as illustrated in FIG. 8, and repeatedly performs the arithmetic processing
as illustrated in Steps S1 to S8 of the flowchart of FIG. 5, for example, so that
the bucket to ground angle θ5 at start of excavation can be brought close to a desired
angle while intervention of an operator's intention is allowed. The desired angle
is preferably an angle (for example, an angle of about 90 degrees) at which a tip
of the bucket 6 is positioned directly below a rotation center of the bucket 6 with
respect to the arm 5.
[Fourth embodiment]
[0111] FIG. 9 is an example of a block diagram illustrating a process of control by the
controller 50 according to a fourth embodiment. In the fourth embodiment, a physical
quantity related to an orientation of a work device is an angle detected by an angle
sensor, a target physical quantity is a target angle that is a target of an angle
of the work device, and a current physical quantity is a current angle that is an
actual angle detected by the angle sensor. Specifically, in the fourth embodiment,
an orientation of the boom 4, an orientation of the arm 5, and an orientation of the
bucket 6 are controlled using an angle of the boom 4, an angle of the arm 5, and an
angle of the bucket 6. In the fourth embodiment, the boom orientation detector 31
is a boom angle sensor, the arm orientation detector 32 is an arm angle sensor, and
the bucket orientation detector 33 is a bucket angle sensor.
[0112] In the fourth embodiment, a target physical quantity includes first to third target
physical quantities, a current physical quantity includes first to third current physical
quantities, and a physical quantity error includes first to third physical quantity
errors. Specifically, the first target physical quantity is a first target angle (boom
target angle) that is a target of an angle of the boom 4, the second target physical
quantity is a second target angle (arm target angle) that is a target of an angle
of the arm 5, and the third target physical quantity is a third target angle (bucket
target angle) that is a target of an angle of the bucket 6. The first current physical
quantity is a first current angle which is an actual angle of the boom 4 detected
by the boom orientation detector 31, the second current physical quantity is a second
current angle which is an actual angle of the arm 5 detected by the arm orientation
detector 32, and the third current physical quantity is a third current angle which
is an actual angle of the bucket 6 detected by the bucket orientation detector 33.
The first physical quantity error is a first angular error that is an error between
the first target angle and the first current angle, the second physical quantity error
is a second angular error that is an error between the second target angle and the
second current angle, and the third physical quantity error is a third angular error
that is an error between the third target angle and the third current angle.
[0113] Similarly to the first embodiment, the controller 50 of the driving device according
to the fourth embodiment may perform arithmetic processing along the flowchart illustrated
in FIG. 5, for example. Hereinafter, an example of arithmetic processing by the controller
50 according to the fourth embodiment will be described with reference to the flowchart
illustrated in FIG. 5. In the fourth embodiment, target work is set to earth removal
work, and excavation work, earth and sand holding and slewing work, and returning
slewing work are set to non-target work.
[0114] At a time point of starting earth and sand loading work, an operator operates at
least one of the operation levers 61A to 64A of the operation devices 61 to 64 to
arrange the boom 4, the arm 5, and the bucket 6 in a desired orientation as illustrated
in the upper diagram (A) in FIG. 6, for example, and, in this state, presses the storage
switch 80.
[0115] When a signal indicating that the storage switch 80 is pressed is input to the controller
50, the target physical quantity setting unit 52 (target orientation setting device
in FIG. 9) determines that input operation to the storage switch 80 is performed (YES
in Step S1), sets an angle of the boom 4 at that time point as the first target angle,
sets an angle of the arm 5 at that time point as the second target angle, and sets
an angle of the bucket 6 at that time point as the third target angle (Step S2). On
the other hand, when determining that input operation to the storage switch 80 is
not performed (NO in Step S1), the target physical quantity setting unit 52 sets the
first to third target angles to a default value (Step S3). The default value may be
a value preset as the first to third target angles and stored in a memory, or may
be the first to third target angles set last time.
[0116] Next, the work determination unit 59 of the controller 50 determines whether the
earth removal work is being performed as described above (Step S4). When the work
determination unit 59 determines that the earth removal work is being performed (YES
in Step S4), the current physical quantity arithmetic unit 53 calculates the first
current angle which is an angle of the boom 4 at that time point based on a detection
signal input from the boom orientation detector 31, calculates the second current
angle which is an angle of the arm 5 at that time point based on a detection signal
input from the arm orientation detector 32, and calculates the third current angle
which is an angle of the bucket 6 at that time point based on a detection signal input
from the bucket orientation detector 33. Then, the physical quantity error arithmetic
unit 54 calculates the first angular error that is an error relating to the boom 4
by using, for example, a formula (first angular error = first target angle - first
current angle), calculates the second angular error that is an error relating to the
arm 5 by using, for example, a formula (second angular error = second target angle
- second current angle), and calculates the third angular error that is an error relating
to the bucket 6 by using, for example, a formula (third angular error = third target
angle - third current angle) (Step S5).
[0117] The controller 50 stores in advance a map (boom map), for example, as illustrated
in FIG. 3, set in advance to control an orientation of the boom 4, stores in advance
a map (arm map), for example, as illustrated in FIG. 3, set in advance to control
an orientation of the arm 5, and stores in advance a map (bucket map), for example,
as illustrated in FIG. 3, set in advance to control an orientation of the bucket 6.
These three maps are individually set in advance so that each of the boom 4, the arm
5, and the bucket 6 performs appropriate operation in the earth removal work. In the
fourth embodiment, in the graph illustrated in FIG. 3, the horizontal axis represents
an angular error (first angular error, second angular error, or third angular error),
and the vertical axis represents the assistance rate (r).
[0118] Next, the assistance rate setting unit 55 sets the first assistance rate (r) which
is an assistance rate for the boom 4 based on the boom map and the first angular error
(e) calculated by the physical quantity error arithmetic unit 54. Similarly, the assistance
rate setting unit 55 sets the second assistance rate (r) which is an assistance rate
for the arm 5 based on the arm map and the second angular error (e) calculated by
the physical quantity error arithmetic unit 54, and sets the third assistance rate
(r) which is an assistance rate for the bucket 6 based on the bucket map and the third
angular error (e) calculated by the physical quantity error arithmetic unit 54 (Step
S6).
[0119] Next, the operator operation value (Lo) at that time point is input to the controller
50. Specifically, when boom operation (the boom lowering operation or the boom raising
operation) is given to the operation lever 61A, the boom operation device 61 inputs
an operator operation value (the first operator operation value (Lo)), which is an
electric signal corresponding to a direction and magnitude of the boom operation,
to the controller 50. Specifically, when the arm pushing operation is given to the
operation lever 62A, the arm operation device 62 inputs an operator operation value
(the second operator operation value (Lo)), which is an electric signal corresponding
to magnitude of the arm pushing operation, to the controller 50. When the bucket pushing
operation is given to the operation lever 63A, the bucket operation device 63 inputs
an operator operation value (the third operator operation value (Lo)), which is an
electric signal corresponding to magnitude of the bucket pushing operation, to the
controller 50.
[0120] The controller 50 stores in advance, for example, a formula (boom arithmetic expression)
as shown in Formula (1) described above, which is set in advance for feedback control
of an orientation of the boom 4, stores in advance, for example, a formula (arm arithmetic
expression) as shown in Formula (1) described above, which is set in advance for feedback
control of an orientation of the arm 5, and stores in advance, for example, a formula
(bucket arithmetic expression) as shown in Formula (1) described above, which is set
in advance for feedback control of an orientation of the bucket 6. These three formulas
are individually set in advance so that each of the boom 4, the arm 5, and the bucket
6 performs appropriate operation in the earth removal work.
[0121] The assistance operation value arithmetic unit 56 (PID controller) calculates the
first assistance operation value (La), which is an assistance operation value for
assisting the boom operation, by using the boom arithmetic expression and the first
angular error (e). Similarly, the assistance operation value arithmetic unit 56 (PID
controller) calculates the second assistance operation value (La), which is an assistance
operation value for assisting the arm pushing operation, by using the arm arithmetic
expression and the second angular error (e), and calculates the third assistance operation
value (La), which is an assistance operation value for assisting the bucket pushing
operation, by using the bucket arithmetic expression and the third angular error (e).
[0122] The operator operation value correction unit 57 calculates the first operator correction
value (Lo') by using Formula (2) described above, the first operator operation value
(Lo) in the boom operation, and the first assistance rate (r). Similarly, the operator
operation value correction unit 57 calculates the second operator correction value
(Lo') by using Formula (2) described above, the second operator operation value (Lo)
in the arm pushing operation, and the second assistance rate (r), and calculates the
third operator correction value (Lo') by using Formula (2) described above, the third
operator operation value (Lo) in the bucket pushing operation, and the third assistance
rate (r).
[0123] The assistance operation value correction unit 58 calculates the first assistance
correction value (La') by using Formula (3) described above, the first assistance
operation value (La) in the boom operation, and the first assistance rate (r). Similarly,
the assistance operation value correction unit 58 calculates the second assistance
correction value (La') by using Formula (3) described above, the second assistance
operation value (La) in the arm pushing operation, and the second assistance rate
(r), and calculates the third assistance correction value (La') by using Formula (3)
described above, the third assistance operation value (La) in the bucket pushing operation,
and the third assistance rate (r).
[0124] Regarding the boom operation, the operation command unit 51 outputs a first total
value that is a total value obtained by adding the first operator correction value
(Lo') and the first assistance correction value (La') as the first control command
Y (Y = Lo × (1 - r) + La × r) that is a final operation value. Further, regarding
the arm pushing operation, the operation command unit 51 outputs a second total value
that is a total value obtained by adding the second operator correction value (Lo')
and the second assistance correction value (La') as the second control command Y (Y
= Lo × (1 - r) + La × r) that is a final operation value. Further, regarding the bucket
pushing operation, the operation command unit 51 outputs a third total value that
is a total value obtained by adding the third operator correction value (Lo') and
the third assistance correction value (La') as the third control command Y (Y = Lo
× (1 - r) + La × r) which is a final operation value (Step S7). The output first control
command Y is input to the proportional valve 45 corresponding to the boom operation
(boom lowering operation or boom raising operation), the output second control command
Y is input to the proportional valve 46 corresponding to the arm pushing operation,
and the output third control command Y is input to the proportional valve 47 corresponding
to the bucket pushing operation.
[0125] On the other hand, when the work determination unit 59 determines that the earth
removal work is not being performed (NO in Step S4), the operation command unit 51
outputs the operator operation value (Lo) corresponding to an operation input from
at least one of the plurality of operation devices 61 to 64 as a control command which
is a final operation value (Step S8).
[0126] As described above, the controller 50 performs the feedback control using the assistance
operation value (La) for bringing the angular error (e) close to zero as illustrated
in FIG. 4 for each of the boom 4, the arm 5, and the bucket 6, and repeatedly performs
the arithmetic processing as illustrated in Steps S1 to S8 of the flowchart of FIG.
5 for each of the boom 4, the arm 5, and the bucket 6. This makes it possible to assist
operator's operation for adjusting an orientation of the boom 4, an orientation of
the arm 5, and an orientation of the bucket 6 to a desired orientation while allowing
intervention of an operator's intention.
[Variation]
[0127] The construction machine driving device according to the embodiment of the present
disclosure is described above, but the present disclosure is not limited to the embodiment,
and includes a variation below, for example.
- (A) In the first embodiment, a physical quantity related to an orientation of a work
device is coordinates of a tip of the bucket 6, and an orientation of the bucket 6
is controlled using coordinates of the tip of the bucket 6. However, the first embodiment
is not limited to such a specific example. For example, an orientation of a work device
may be controlled using at least one of coordinates of a specific part (for example,
a tip of the boom 4) in the boom 4, coordinates of a specific part (for example, a
tip of the arm 5) in the arm 5, and coordinates of a specific part (for example, a
tip of the bucket 6) in the bucket 6. Specifically, for example, an orientation of
the arm 5 may be controlled using coordinates of a tip of the arm 5, and an orientation
of the bucket 6 may be controlled using coordinates of a tip of the bucket 6. Further,
an orientation of the boom 4 may be controlled using coordinates of a tip of the boom
4, an orientation of the arm 5 may be controlled using coordinates of a tip of the
arm 5, and an orientation of the bucket 6 may be controlled using coordinates of a
tip of the bucket 6. Specifically, in a case where a tip of the arm 5 is set as the
specific part and a tip of the bucket 6 is set as the specific part in the first embodiment,
the controller 50 preferably controls an orientation of the arm 5 by using a current
physical quantity that is actual coordinates of the tip of the arm 5, a target physical
quantity that is a target of coordinates of the tip of the arm 5, a physical quantity
error that is an error between these, an operator operation value, an assistance operation
value, an operator correction value, and an assistance correction value, and preferably
controls an orientation of the bucket 6 by using a current physical quantity that
is actual coordinates of the tip of the bucket 6, a target physical quantity that
is a target of coordinates of the tip of the bucket 6, a physical quantity error that
is an error between these, an operator operation value, an assistance operation value,
an operator correction value, and an assistance correction value.
- (B) In the second embodiment, a physical quantity related to an orientation of a work
device is a cylinder length, an orientation of the arm 5 is controlled using a cylinder
length of the arm cylinder 8, and an orientation of the bucket 6 is controlled using
a cylinder length of the bucket cylinder 9. However, the second embodiment is not
limited to such a specific example. For example, an orientation of a work device may
be controlled using at least one of a cylinder length of the boom cylinder 7, a cylinder
length of the arm cylinder 8, and a cylinder length of the bucket cylinder 9.
- (C) In the third embodiment, a physical quantity related to an orientation of a work
device is a height of a tip of the bucket 6, and an orientation of the work device
is controlled using a height of the tip of the bucket 6, but the present invention
is not limited to such a specific example. For example, an orientation of a work device
may be controlled using at least one of a height of a specific part (for example,
a tip of the boom 4) in the boom 4, a height of a specific part (for example, a tip
of the arm 5) in the arm 5, and a height of a specific part (for example, a tip of
the bucket 6) in the bucket 6.
- (D) A physical quantity related to an orientation of a work device may include, for
example, at least one of the boom angle 01, the arm angle θ2, the bucket angle Θ3,
and an inclination angle of the upper slewing body 2.
- (E) Regarding construction machine system
[0128] The driving device according to the present disclosure can also be applied to a construction
machine system. The construction machine system includes the construction machine
100, and the remote operation devices 61 to 64 which are the operation device 61 to
64 arranged at a position away from the construction machine 100. The construction
machine 100 may include a part or whole of the controller 50, and a part or whole
of the controller 50 may be arranged at a remote location. The construction machine
100 is configured to operate based on operation by an operator given to the remote
operation devices 61 to 64. The operator operation value (Lo) output from the remote
operation devices 61 to 64 is transmitted to the construction machine 100 by wireless
communication or wired communication. Further, an image of a work site where the construction
machine 100 performs work is captured by a camera (not illustrated), captured data
is transmitted to a remote place by wireless communication or wired communication,
and a display device arranged at the remote place displays an image of the work site
in real time by using the transmitted data. An operator operates the remote operation
devices 61 to 64 while viewing the display device at a remote place. In a case where
the remote operation devices 61 to 64 are operated at a remote place in the above
manner, it is difficult for an operator to grasp a situation of a work site such as
a sense of perspective of a work site as compared with a case where the operator gets
on the construction machine 100 (actual machine) and operates an operation device.
Therefore, as the driving device according to the present disclosure is applied to
a system for such remote control, an effect of reducing burden on an operator by assistance
of the driving device becomes more remarkable in work of adjusting a work device to
a predetermined orientation.
(F) Regarding operation device
[0129] In a case where each of the operation devices 61 to 64 is constituted by an operation
device including a remote control valve, the construction machine 100 includes a plurality
of pilot pressure sensors (not illustrated) that detect pressure of pilot oil output
from the remote control valve according to a lever operation quantity that is magnitude
of an operation given to an operation lever of each of the operation devices 61 to
64. Each of the plurality of pilot pressure sensors inputs an operation value, which
is a signal corresponding to detected pressure of pilot oil, to the controller 50
as an operator operation value. Further, an electromagnetic proportional valve is
arranged between each remote control valve and a control valve corresponding to each
remote control valve, and the electromagnetic proportional valve reduces pressure
of pilot oil based on a control command from the controller 50 and supplies the reduced
pilot pressure to a pilot port of a corresponding control valve. In a case where pressure
larger than pressure of pilot oil output from the remote control valve is supplied
to a pilot port of a control valve according to a lever operation quantity, the controller
50 may control a second electromagnetic proportional valve different from the electromagnetic
proportional valve so that secondary pressure of the second electromagnetic proportional
valve is selected to a high level in a shuttle valve (not illustrated) to be supplied
to the pilot port of the control valve.
(G) Regarding input device
[0130] The driving device may further include the input device 90 (see FIG. 2) that receives
input by an operator for correcting the assistance rate (r), and the controller 50
may be configured to correct the assistance rate (r) based on input by the operator
to the input device 90. In this configuration, since an operator can correct the assistance
rate (r), degree of intervention of an operator's intention can be adjusted according
to the preference of the operator.
[0131] Specifically, for example, an operator inputs an input value (r') for correcting
the assistance rate (r) to the input device 90. The operator operation value correction
unit 57 of the controller 50 may calculate the operator correction value (Lo') by
using, for example, a formula "Lo × (1 - miner, r'))", and the assistance operation
value correction unit 58 may calculate the assistance correction value (La') by using,
for example, a formula "La × miner, r')". Then, the operation command unit 51 may
output a total value obtained by adding the operator correction value (Lo') and the
assistance correction value (La') as the control command Y (Y = Lo × (1 - min(r, r'))
+ La × min(r, r')) which is a final operation value. Note that "min(r, r')" in the
above formula means that a smaller one of the assistance rate (r) and the input value
(r') is employed for calculation.
[0132] Further, the operator operation value correction unit 57 of the controller 50 may
calculate the operator correction value (Lo') by using, for example, a formula "Lo
× (1 - r) × (1 - r')", and the assistance operation value correction unit 58 may calculate
the assistance correction value (La') by using, for example, a formula "La × r × r'".
Then, the operation command unit 51 may output a total value obtained by adding the
operator correction value (Lo') and the assistance correction value (La') as the control
command Y (Y = Lo × (1 - r) × (1 - r') + La × r × r') which is a final operation value.
(H) Regarding notification device
[0133] As illustrated in FIG. 2, the driving device may further include a notification device
70 (an example of a teaching device) for notifying an operator of a situation of control
by the controller 50, and the controller 50 may be configured to control operation
of the notification device so that output from the notification device 70 changes
according to the assistance rate (r). The notification device 70 outputs, for example,
sound, an image, vibration (for example, vibration of an operation lever), and the
like. With this configuration, an operator can perform work for adjusting an orientation
of a work device to a desired orientation while roughly grasping a situation of control
by the controller 50 based on the assistance rate (r). By the above, since the operator
can recognize that assistance control by the controller 50 is being performed, a sense
of security of the operator at the time of operation is improved. In this case, the
controller 50 is preferably configured to control operation of the notification device
so that output from the notification device 70 changes according to magnitude of the
assistance rate (r). By the above, the operator can perform work for adjusting an
orientation of a work device to a desired orientation while more accurately grasping
a situation of control by the controller 50 based on the assistance rate (r).
[0134] Further, the controller 50 may be configured to control operation of the notification
device 70 so that output from the notification device 70 changes according to the
physical quantity error (e). With this configuration, an operator can perform work
for adjusting an orientation of a work device to a desired orientation while roughly
grasping a situation of control by a controller based on the physical quantity error
(e). By the above, the operator can operate an operation device while grasping a sense
of distance until a work device reaches a desired orientation (target orientation),
and thus a sense of security of the operator at the time of operation is improved.
In particular, in a case where the operator is an unskilled person, improvement of
an ability to grasp a sense of distance of the unskilled person can be expected.
[0135] Further, in this case, the controller 50 is preferably configured to control operation
of the notification device so that output from the notification device 70 changes
according to magnitude of the physical quantity error (for example, a coordinate error,
a height error, a distance error, a length error, an angular error, or the like).
By the above, an operator can perform work for adjusting an orientation of a work
device to a desired orientation while more accurately grasping the physical quantity
error (e), that is, the sense of distance.
[0136] In the specific example illustrated in FIG. 9, the controller 50 controls operation
of the notification device 70 so that an alarm sound from an alarm sound generation
device as the notification device 70 changes according to an angular error. The controller
50 may be configured to change a type of sound according to the error (e). By the
above, an operator can recognize a distance until a work device reaches a desired
orientation (target orientation) through a change in a type of sound, so that a sense
of security is improved. Further, the controller 50 may be configured to change a
type of sound according to the assistance rate (r). By the above, since the operator
can recognize that assistance control by the controller 50 is being performed, a sense
of security of the operator at the time of operation is improved.
(I) Regarding target physical quantity
[0137] The controller 50 may be configured to set a plurality of target physical quantities,
determine work being performed by the construction machine 100, and select a target
physical quantity corresponding to the determined work among the plurality of target
physical quantities. In this configuration, for example, in a case where a plurality
of different pieces of work are continuously performed, an operator does not need
to select a target physical quantity for each piece of work, so that burden on the
operator is reduced. A specific example is as described below.
[0138] In a case where earth and sand loading work, which is a series of pieces of work
including excavation work, earth and sand holding and slewing work, earth removal
work, and returning slewing work, is repeatedly performed at a work site, the earth
removal work and the returning slewing work may be set to the target work described
above, and the excavation work and the earth and sand holding and slewing work may
be set to non-target work. In this case, before the series of pieces of work is started,
the controller 50 sets and stores a target physical quantity for the earth removal
work and a target physical quantity for the returning slewing work. Then, in the series
of pieces of work, the work determination unit 59 of the controller 50 determines
work performed by the construction machine 100, and the operation command unit 51
outputs a total value obtained by adding the operator correction value (Lo') and the
assistance correction value (La') as the control command Y (Y = Lo × (1 - r) + La
× r) which is a final operation value in a case where the earth removal work or the
returning slewing work is performed. On the other hand, in a case where neither the
earth removal work nor the returning slewing work is performed, the operation command
unit 51 outputs the operator operation value (Lo) corresponding to an operation input
from at least one of the plurality of operation devices 61 to 64 as a control command
which is a final operation value.
[0139] (J) In the embodiment described above, the controller 50 calculates the assistance
correction value (La') by multiplying the assistance operation value (La) by the assistance
rate (r), and calculates the operator correction value (Lo') by multiplying the operator
operation value (Lo) by a value obtained by subtracting the assistance rate (r) from
a preset setting value (for example, "1"), but the embodiment is not limited to such
a mode. The controller 50 may calculate the assistance correction value (La') and
the operator correction value (Lo') without using an assistance rate. That is, the
controller 50 may correct the operator operation value (Lo) corresponding to an operation
by an operator to the operator correction value (Lo') based on a map set in advance
such that the operator correction value (Lo') becomes smaller when the physical quantity
error (e) is small as compared with when the physical quantity error (e) is large.
Further, the controller 50 may correct the assistance operation value (La) to the
assistance correction value (La') based on a map set in advance such that the assistance
correction value (La') becomes a larger value when the physical quantity error (e)
is small as compared with when the physical quantity error (e) is large.
(K) Regarding assistance by image
[0140] The driving device of the construction machine 100 according to each of the embodiments
described above may further include a display device (an example of a teaching device),
and the controller 50 may be configured to cause the display device to display an
actual orientation image which is an image relating to an actual orientation of at
least one work device of the plurality of work devices and a target orientation image
which is an image relating to a target orientation of the at least one work device.
The display device may be, for example, a display arranged at a position that can
be viewed by an operator in a cabin of the upper slewing body 2, or may be a head
mounted display that can be worn by the operator. Further, the display device may
be, for example, a device capable of displaying an image on front glass of the cabin.
Further, in a case where the driving device according to the present disclosure is
applied to the construction machine system as described above, the display device
may be arranged at a remote place. That is, the display device may be a device that
can be viewed by an operator who operates the remote operation devices 61 to 64 arranged
at a position away from the construction machine 100.
[0141] FIG. 10 is a diagram illustrating an example of a display device 92. In the specific
example illustrated in FIG. 10, the controller 50 displays an image in which the entire
construction machine 100 including a plurality of work devices is viewed from the
side. The image drawn by a solid line in FIG. 10 includes an actual orientation image
which is an image relating to an actual orientation of each of the lower travelling
body 1, the upper slewing body 2, the boom 4, the arm 5, and the bucket 6 at that
time point. The actual orientation image may be, for example, an actual image of at
least one work device captured by a camera, or may be an image created by the controller
50 based on the orientation information input from the orientation information acquisition
unit to the controller 50.
[0142] The image depicted by a broken line in FIG. 10 includes a boom target orientation
image related to a target orientation of the boom 4, an arm target orientation image
related to a target orientation of the arm 5, and a bucket target orientation image
related to a target orientation of the bucket 6. The boom target orientation image
is an image corresponding to the target physical quantity (boom target physical quantity)
related to an orientation of the boom 4 set by the target physical quantity setting
unit 52. The arm target orientation image is an image corresponding to a target physical
quantity (arm target physical quantity) related to an orientation of the arm 5 set
by the target physical quantity setting unit 52. The bucket target orientation image
is an image corresponding to a target physical quantity (bucket target physical quantity)
related to an orientation of the bucket 6 set by the target physical quantity setting
unit 52.
[0143] The controller 50 causes the display device 92 to display a boom target orientation
image, an arm target orientation image, and a bucket target orientation image superimposed
on an actual orientation image of the boom 4, the arm 5, and the bucket 6. By the
above, an operator can recognize, through the image displayed on the display device
92, a gap between a target orientation of the boom 4, the arm 5, and the bucket 6
and an actual orientation of these. In particular, in a case where an operator is
an unskilled person, the unskilled person is expected to effectively improve an operation
technique by operating an operation device while recognizing the gap through an image
displayed on the display device 92.
[0144] FIG. 11 is a diagram illustrating another example of the display device 92. In the
specific example illustrate in FIG. 11, the controller 50 displays an image assuming
a viewpoint from an operator sitting on a driver's seat in a cabin. A left image drawn
by a solid line in FIG. 11 is an image (actual orientation image) related to an actual
orientation of each of the arm 5 and the bucket 6 at that time point. The actual orientation
image may be, for example, an actual image of at least one work device captured by
a camera, or may be an image created by the controller 50 based on the orientation
information. Further, in a case where the display device is a device capable of displaying
an image on front glass of a cabin, the actual orientation image may be an image created
by the controller 50 based on the orientation information, or may be an actual image
of the arm 5 and the bucket 6 visible through the front glass.
[0145] A right image drawn by a broken line in FIG. 11 is a bucket target orientation image
related to a target orientation of the bucket 6. The bucket target orientation image
is an image corresponding to a target physical quantity related to an orientation
of the bucket 6 set by the target physical quantity setting unit 52. A central image
drawn by a two-dot chain line in FIG. 11 is an intermediate orientation image (bucket
intermediate orientation image) related to an intermediate orientation between an
actual orientation of the bucket 6 and a target orientation of the bucket 6. The controller
50 causes the display device 92 to display an actual orientation image of the arm
5 and the bucket 6, a bucket target orientation image, and a bucket intermediate orientation
image. By the above, an operator can recognize, through the image displayed on the
display device 92, a gap between a target orientation of the bucket 6 and an actual
orientation of the bucket 6. Moreover, an operator can recognize, through the bucket
intermediate orientation image displayed on the display device 92, what kind of intermediate
orientation the bucket 6 takes until reaching a target orientation from an actual
orientation.
[0146] Further, the controller 50 may cause the display device 92 to further display an
image of an object present around the bucket 6 in addition to an actual orientation
image of the bucket 6, a bucket target orientation image, and a bucket intermediate
orientation image. In this case, an operator can determine whether the bucket 6 collides
with an object present around the bucket 6 while the bucket 6 reaches a target orientation
from an actual orientation through an intermediate orientation.
[0147] For example, the controller 50 may calculate the intermediate orientation based on
information related to an operation speed of the bucket 6. By the above, the controller
50 can relatively accurately predict the intermediate orientation. Specifically, an
operation speed of the bucket 6 includes a direction in which the bucket 6 operates
and a speed at which the bucket 6 operates. The controller 50 may use information
related to an operation speed of the bucket 6 at that time point and, for example,
a set time set in advance or a set time set based on input by an operator to calculate,
as the intermediate orientation, an orientation of the bucket 6 after lapse of the
set time from that time point. However, calculation of the intermediate orientation
by the controller 50 is not limited to the above specific example. For example, the
controller 50 may calculate an orientation at a central point between an actual orientation
of the bucket 6 and a target orientation of the bucket 6 by using, for example, a
method such as linear interpolation.
[0148] The information related to an operation speed of the bucket 6 may be an operator
operation value corresponding to an operation given to at least one of the plurality
of operation devices 61 to 64. Further, the information related to an operation speed
of the bucket 6 may be a total value obtained by adding the operator correction value
(Lo') and the assistance correction value (La'). Further, the information related
to an operation speed of the bucket 6 may be an operation speed of the bucket 6 actually
detected by a speed sensor (not illustrated).
(L) Regarding release of assistance control
[0149] In a case where a non-assistance condition, which is a predetermined condition, is
satisfied while the controller 50 performs assistance control for controlling the
orientation of the work device by using the total value, the controller 50 may be
configured to switch from the assistance control to control based on an operation
given to an operation device (normal control). In this variation, in a case where
the non-assistance condition is satisfied while the controller 50 performs assistance
control, the controller 50 switches from the assistance control to the normal control.
By the above, assist by the controller 50 is released, and the work device performs
operation corresponding to the operation given to an operation device by an operator.
This makes it possible to release assistance and appropriately operate a work device
according to an operator's intention in a case where a situation in which it is not
preferable to continue assistance control as it is occurs.
[0150] Examples of the situation in which it is not preferable to continue assistance control
as it is include a situation in which a work device needs to avoid an obstacle, a
situation in which earth removal from a bucket is completed before an orientation
of a work device reaches a target orientation when earth removal work is being performed,
and the like.
[0151] The non-assistance condition may include switching from the operation given to the
operation device in the assistance control to another operation set in advance. In
a case where the above situation occurs, an operator often switches from an operation
given to an operation device in assistance control to another operation. Specifically,
for example, when a situation in which a work device needs to avoid an obstacle occurs,
an operator tries to avoid contact between the work device and the obstacle by switching
to an operation in a direction different from (for example, a direction opposite to)
a direction of a lever operation given to the work device until then. When assist
by the controller 50 is released under such a situation, contact between the work
device and the obstacle is more effectively avoided. Further, when a situation in
which earth removal from a bucket is completed occurs during earth removal work, an
operator switches to the arm pulling operation in a direction opposite to the arm
pushing operation which is given to a work device until then, in order to perform
a next piece of work (for example, returning slewing work). When assist by the controller
50 is released under such a situation, continuity of a plurality of pieces of work
is more effectively ensured. As described above, switching from the operation given
to the operation device in the assistance control to another operation set in advance
is an indication for determining that a situation in which it is not preferable to
continue assistance control as it is occurs.
[0152] However, the non-assistance condition is not limited to the above specific example,
and may include, for example, switching from a state in which the physical quantity
error decreases to a state in which the physical quantity error increases, and elapsed
time from the switching exceeding a time threshold which is a preset threshold.
[0153] As described above, according to the present disclosure, the construction machine
driving device capable of assisting an operation by an operator for adjusting an orientation
of a work device to a desired orientation while allowing intervention of an operator's
intention, and a construction machine and a construction machine system including
the construction machine driving device are provided.
[0154] A construction machine driving device to be provided includes an operation device
to which an operation by an operator for moving a work device with respect to a machine
body is given, and a controller, in which the controller sets a target physical quantity
that is a target of a physical quantity related to an orientation of the work device,
calculates a current physical quantity that is a physical quantity related to an actual
orientation of the work device, calculates a physical quantity error that is an error
between the target physical quantity and the current physical quantity, calculates
an assistance operation value for assisting the operation of the operator, corrects
an operator operation value corresponding to the operation to an operator correction
value such that the operator correction value becomes smaller when the physical quantity
error is small as compared with when the physical quantity error is large, corrects
the assistance operation value to an assistance correction value such that the assistance
correction value becomes larger when the physical quantity error is small as compared
with when the physical quantity error is large, and controls the orientation of the
work device by using a total value obtained by adding the operator correction value
and the assistance correction value.
[0155] The controller of the construction machine controls an orientation of a work device
by using a total value obtained by adding an operator correction value corrected to
become a small value when a physical quantity error is small as compared with when
the physical quantity error is large and an assistance correction value corrected
to become a large value when the physical quantity error is small as compared with
when the physical quantity error is large. Therefore, the controller of the construction
machine can assistance operation by an operator for adjusting an orientation of a
work device to a desired orientation while allowing intervention of an operator's
intention. Specifically, when a physical quantity error is large, a proportion of
contribution of an operator operation value to the total value can be made large,
and when the physical quantity error is small, a proportion of contribution of an
assistance operation value to the total value can be made large. Therefore, when a
physical quantity error is large, significant intervention of an operator's intention
is allowed, and when the physical quantity error is small, that is, when an orientation
of a work device approaches a target orientation and the orientation of the work device
is finely adjusted, intervention of an operator's intention can be made less as compared
with when the physical quantity error is large, and an orientation of the work device
can be easily adjusted to a target orientation by assistance of the controller. By
the above, it is possible to achieve both intervention of an operator's intention
and easy adjustment of an orientation of a work device.
[0156] The controller preferably sets an assistance rate such that the assistance rate becomes
a larger value when the physical quantity error is small as compared with when the
physical quantity error is large, calculates the assistance correction value by multiplying
the assistance operation value by the assistance rate, and calculates the operator
correction value by multiplying the operator operation value by a value obtained by
subtracting the assistance rate from a preset setting value. In this configuration,
as a physical quantity error becomes smaller, that is, as an orientation of a work
device approaches a target orientation, an operator correction value can be continuously
made smaller and an assistance correction value can be continuously made larger. This
enables smooth transition from a state in which operation by an operator is mainly
performed to a state in which assist by the controller is mainly performed in a process
in which an orientation of a work device approaches a target orientation.
[0157] The driving device may further include an input device that receives input by the
operator for correcting the assistance rate, in which the controller may correct the
assistance rate based on the input by the operator. In this configuration, since an
operator can correct an assistance rate, degree of intervention of an operator's intention
can be adjusted according to the preference of the operator.
[0158] The driving device preferably further includes a notification device for notifying
the operator of a situation of control by the controller, and the controller preferably
controls operation of the notification device such that output from the notification
device changes according to the assistance rate. With this configuration, an operator
can perform work for adjusting an orientation of a work device to a desired orientation
while roughly grasping a situation of control by the controller based on an assistance
rate.
[0159] The driving device preferably further includes a notification device for notifying
the operator of a situation of control by the controller, in which the controller
preferably controls operation of the notification device such that output from the
notification device changes according to the physical quantity error. With this configuration,
an operator can perform work for adjusting an orientation of a work device to a desired
orientation while roughly grasping a situation of control by a controller based on
the physical quantity error.
[0160] The controller may calculate the assistance operation value based on the physical
quantity error such that the physical quantity error approaches zero. In this configuration,
the controller can effectively perform assistance to bring an orientation of a work
device close to a target orientation.
[0161] The controller may set a plurality of target physical quantities including the target
physical quantity, determine work being performed by the construction machine, and
select a target physical quantity corresponding to the determined work from the plurality
of target physical quantities. In this configuration, the controller can select an
appropriate target physical quantity for each piece of work. Therefore, in this configuration,
for example, in a case where a plurality of different pieces of work are continuously
performed, an operator does not need to select a target physical quantity for each
piece of work, so that burden on the operator is reduced.
[0162] The controller preferably determines whether or not target work that is work set
in advance as a target of assistance by the controller is performed, controls the
orientation of the work device by using the total value in a case where the target
work is performed, and controls the orientation of the work device by using the operator
operation value in a case where the target work is not performed. In this configuration,
the controller can perform control according to a determination result as to whether
or not target work is being performed. By the above, an operator can smoothly perform
a plurality of series of pieces of work including target work and other pieces of
work.
[0163] The work device may include a bucket, and the physical quantity error may be a value
corresponding to a distance between a tip of the bucket and a working surface. In
this configuration, for example, in a case of performing excavation work, an operator
can easily arrange a tip of a bucket at a desired position that is an excavation start
position of a working surface while receiving assistance from the controller.
[0164] The driving device may further include a display device, in which the controller
may cause the display device to display an actual orientation image which is an image
related to an actual orientation of the work device and a target orientation image
which is an image related to a target orientation of the work device. By the above,
an operator can recognize, through an image displayed on the display device, a gap
between a target orientation and an actual orientation of a work device. In particular,
in a case where an operator is an unskilled person, the unskilled person is expected
to effectively improve an operation technique by operating an operation device while
recognizing the gap through an image displayed on the display device.
[0165] The controller may cause the display device to further display an intermediate orientation
image which is an image related to an intermediate orientation between the actual
orientation and the target orientation. By the above, an operator can recognize, through
an image displayed on the display device, what kind of intermediate orientation a
work device takes until reaching a target orientation from an actual orientation.
[0166] The controller may calculate the intermediate orientation based on information related
to an operation speed of the work device. By the above, the controller can relatively
accurately predict the intermediate orientation.
[0167] In a case where a non-assistance condition, which is a predetermined condition, is
satisfied while the controller performs assistance control for controlling the orientation
of the work device by using the total value, the controller preferably switches from
the assistance control to control based on an operation given to the operation device
(normal control). In this configuration, in a case where the non-assistance condition
is satisfied while assistance control is performed, the controller switches from the
assistance control to the normal control, so that assistance by the controller is
released, and the work device performs an operation corresponding to the operation
given to the operation device by an operator. This makes it possible to release assistance
and appropriately operate a work device according to an operator's intention in a
case where a situation in which it is not preferable to continue assistance control
as it is occurs.
[0168] The non-assistance condition preferably includes switching from the operation given
to the operation device in the assistance control to another operation set in advance.
In a case where the above situation occurs, an operator often switches from an operation
given to an operation device in assistance control to another operation. Therefore,
switching from the operation given to the operation device in the assistance control
to another operation set in advance is an indication for determining that a situation
in which it is not preferable to continue assistance control as it is occurs.
[0169] A construction machine to be provided includes the machine body, the work device,
and the driving device described above. The construction machine can assistance operation
by an operator for adjusting an orientation of a work device to a desired orientation
while allowing intervention of an operator's intention.
[0170] A construction machine system to be provided includes the driving device described
above, in which the operation device is a remote operation device arranged at a place
away from the construction machine. In this construction machine system, in a case
where an operator operates a remote operation device at a remote place to cause a
construction machine to perform work at a work site, the controller can assistance
operation by an operator while allowing intervention of an operator's intention. Specifically,
in a case where a remote operation device is operated at a remote place, it is difficult
for an operator to grasp a situation of a work site such as a sense of perspective
of a work site as compared with a case where the operator gets on a construction machine
(actual machine) and operates an operation device. Therefore, as the driving device
according to the present disclosure is applied to a system for such remote control,
an effect of reducing burden on an operator by assistance of the driving device becomes
more remarkable in work of adjusting a work device to a predetermined orientation.