Field
[0001] The present disclosure relates to a control apparatus for a lifting device, to a
corresponding method and computer program for a lifting device, to a remote-control
device, and to a corresponding method and computer program for a remote-control device.
Background
[0002] The determination of the support force in vehicle support devices, such as support
legs, is known from the state of the art. One way of measuring this support force
is via electrical or electronic force measuring devices, which are preferably arranged
in the support plate, i.e. near the point of application of the support force. Another
method of determining the support force is to measure the pressure in the cylinder
itself (on the piston and rod side). The measured pressures can be used to calculate
the support force. Instead of measuring the pressure in the cylinder being used to
extend and retract the vehicle support devices, the pressure can also be measured
in a separate hydraulic circuit, as shown in
EP 2 815 135 B1.
[0003] In some systems, the support force being measured is used to limit the operation
of a crane. For example, a threshold can be entered for the support forces occurring
at the support legs of the crane and, if the current support forces at one of the
support legs are exceeded, further movements of the crane that increase this support
force can be blocked. In many systems, the threshold being used is the same threshold
for every support leg. In
EP 2 909 127 B1, separate thresholds are used for the different support legs.
[0004] JP2010159148A describes a jack reaction force display device for a work vehicle designed to monitor
the safety of outrigger grounding in real time. The system utilizes extension width
detectors and jack reaction force detectors to establish a reference reaction force
based on the outrigger's extension; it then selects specific display colors or shapes
based on the deviation of the actual reaction force from this reference and renders
them on a monitor to provide visual safety information.
[0005] CN110950248A describes a crane outrigger control system and method utilizing a mobile APP and
Bluetooth technology. The system enables the transmission of control commands and
the reading of length and pressure parameters via a controller that converts Bluetooth
signals to CAN signals for the vehicle controller. It features a safety mechanism
where exceeding predefined upper or lower limits triggers vibration alerts on the
APP and audible/visual alarms from the controller, while simultaneously issuing motion-limiting
commands to enhance operational safety and accuracy.
[0006] WO2014059457A1 describers a method for securing the position of a crane with at least two support
legs for supporting said crane on surfaces. At least one threshold is entered for
the support legs, and movements which increase the supporting force are blocked if
at least one threshold is exceeded by a current supporting force, the thresholds for
each of the support legs being entered individually and/or for subgroups of support
legs.
[0007] There may be a desire for providing an improved concept for operating a lifting device.
Summary
[0008] This desire is addressed by the subject matter of the independent claims.
[0009] The proposed concept is based on the insight that the aforementioned systems are
based on limiting the movement of the crane when a force exceeding a threshold indicating
a maximally tolerable force is detected. These systems are only activated when the
maximally tolerable force is reached, effectively shutting down operation of the crane
to prevent accidents. For operators of lifting devices, the measured support forces
are of major interest well before the threshold is reached, to improve the operation
of the lifting device by the operator. Therefore, instead or in addition to waiting
for a maximally tolerable threshold to be exceeded (and the operation of the crane
being limited accordingly), the user is provided with an indication of the support
force, based on the comparison with another threshold (that can be set by the user).
[0010] Some aspects of the present disclosure relate to a control apparatus for a lifting
device. The control apparatus comprises interface circuitry and processor circuitry.
The processor circuitry is configured to receive, via the interface circuitry, force
measurements from force sensors associated with support legs being used to stabilize
the lifting device. The processor circuitry is configured to compare the force measurements
to at least one force threshold. The processor circuitry is configured to provide,
via the interface circuitry, a control signal to a remote-control device to control
at least one indicator of the remote-control device based on the comparison. By providing
a control signal to control an indicator, the operator of the lifting device can be
supplied with valuable information on the current support force measured for the support
legs. As a result, the operation of the lifting device by the operator can be improved.
[0011] In many cases, the operator of a lifting device, such as a vehicle-mounted crane, can
be improved if the operator can see the lifting device in the context of its surroundings.
For this purpose, the operator may use a remote-control device (e.g., a remote-control
device that is communicatively coupled with the control apparatus or lifting device,
e.g., via a wired or wireless communication path) to control the lifting device and
the support legs. To improve the operation of the lifting device (and the support
legs) while the operator is using the remote-control device, the control signal is
provided to the remote-control device, to control an indicator of the remote-control
device, so that the operator becomes aware of the indication as he or she is controlling
the lifting device via the remote-control device. Accordingly, the processor circuitry
is configured to provide the control signal to a remote-control device.
[0012] There are various modalities that can be used to grab the attention of the operator.
For example, the processor circuitry may be configured to provide the control signal
to the remote-control device to trigger a vibration at the remote-control device.
A vibration can be perceived by the operator even in noisy environments and while
having their eyes on the lifting device rather than the remote-control device, thus
improving the likelihood that the operator becomes aware of the indication.
[0013] Additionally, or alternatively, the indication can be displayed by the remote-control
device, e.g., using light-emitting diodes (LEDs) or a display (e.g., of a user interface)
of the remote-control device. For example, the processor circuitry may be configured
to provide the control signal to the remote-control device to trigger a visual indicator
representing the comparison to be displayed by the remote-control device. Visual indications
provide a means to provide precise information to the operator, e.g., using numbers
to represent the measured forces and the threshold(s). Different colors (e.g., in
the user interface, or when using the LEDs) can be used to let the operator take in
the urgency of the situation at a glance. For example, a red color can be used to
represent scenarios in which the comparison between the at least one threshold and
the force measurements indicates a critical situation, e.g., as a highest threshold
of the at least one threshold has been reached or surpassed. A yellow color can be
used to represent scenarios in which the comparison between the at least one threshold
and the force measurements indicate a mildly critical situation, e.g., as a second-highest
threshold of the at least one threshold has been reached or surpassed. A green color
can be used in noncritical scenarios, e.g., when none of the thresholds have been
reached or surpassed.
[0014] Another way of grabbing the operator's attention is by using one or more indicators
that are arranged at the lifting device or at a carrier vehicle hosting the lifting
device. For example, the processor circuitry may be configured to further provide
the control signal to an optical system (e.g., LEDs or other types of lights arranged
at the lifting device, e.g., at a status board or at the support legs themselves)
or acoustic system (e.g., loudspeakers) of the lifting device or to an optical system
(e.g., LEDs or other types of lights arranged at the carrier vehicle, e.g., at a status
board or at the support legs themselves) or acoustic system of a carrier vehicle hosting
the lifting device. This way, the operator can be made aware of the result of the
comparison while looking at the lifting device or support legs.
[0015] In many cases, lifting devices are used in non-even territory. For example, some of
the support legs may be placed on a sidewalk, while others are placed on the street,
or the ground may be sloped. Moreover, due to slight shifts in the center of gravity
of the lifting device, different amounts of force may be applied on the support legs.
Therefore, force measurements may be obtained, e.g., substantially in real-time, separately
for each of the support legs. In other words, the force measurements may comprise,
for two or more support legs, separate force measurements being taken by a force sensor
associated with the respective support leg. This way, a more precise determination
of the respective support forces can be made.
[0016] In general, each of the support legs is constrained by the amount of support force
it is allowed to take. Therefore, the force measurements may be compared separately
to the at least one threshold. In other words, the processor circuitry may be configured
to compare the force measurements separately to the at least one force threshold.
[0017] In many cases, using a single support force threshold is sufficient, as the condition
of the ground and/or the security or legal requirements are the same for each of the
support legs. In other words, the processor circuitry may be configured to compare
the force measurements to the same force threshold. In some cases, e.g., when some
of the support legs are placed on the street while others are placed on the sidewalk,
specifying multiple different force thresholds for the different ground structures
may be useful. In other words, the processor circuitry may be configured to compare
the force measurements to support leg-specific thresholds. This improves operation
of the support legs in heterogeneous ground scenarios.
[0018] In general, a vital information for the operator is whether the support force of
a support leg reaches or surpasses some threshold, e.g., a user-defined threshold,
or a threshold derived from laws or regulations. For example, user-defined thresholds
may be used that are set below the threshold derived from laws or regulations (e.g.,
at 75%, 80%, 90% of the security, legal or regulatory threshold), to make the operator
aware that the measured forces are close to reaching the legal or regulatory thresholds.
Accordingly, the processor circuitry may be configured to provide the control signal
such that, if the force measurement for a support leg reaches or surpasses the threshold
for the support leg, the at least one indicator is controlled to indicate that the
force measurement for the support leg has reached or surpassed the threshold. This
way, the operator does not have to check the measured forces but can rely on there
being an indication when some relevant threshold is reached, which makes controlling
the lifting device or the support legs less cognitively complex.
[0019] In some cases, e.g., when the indication is provided via lights that are placed on
the support legs themselves, the operator might not see each of the indicators at
once. Therefore, if a threshold is surpassed for the force measurements of one support
leg, the indicators for multiple support leges may be used to display the indication,
to ensure that the indication is seen by the operator. For example, the processor
circuitry may be configured to provide the control signal such, that, if the force
measurement for a support leg reaches or surpasses the threshold for the support leg,
the at least one indicator may be controlled to indicate, at an indicator portion
related to at least two support legs, that the force measurement for at least one
support leg has reached or surpassed the threshold. This way, the operator is aware
of the result of the comparison for several support legs, even if the operator can
only perceive the operator for a subset of the support legs.
[0020] The proposed concept is particularly useful in combination with operator-defined
thresholds (that sit below the security, legal or regulatory thresholds), to enable
setting thresholds that indicate to the operator that he or she is to proceed with
caution when the respective threshold is reached or surpassed. For example, the processor
circuitry may be configured to receive, from a remote-control device, the at least
one force threshold. This way, a threshold being used for the comparison can be input
by the operator based on the scenario, e.g., ground conditions, at hand.
[0021] In some cases, different stabilizer pads, i.e., pads that are attached to or part
of the feet of the respective support legs, may be available for use with the support
legs. For example, depending on the ground conditions or available space, different
stabilizer pads. If the force measurements represent the pressure inside a hydraulic
system of the support legs, or if the force measurements represent the force on the
support legs (and not on the ground), the size of the stabilizer pads is relevant
for interpreting the force measurements. In particular, changing the pad size results
in a change in pressure, which allows the pressure of the stabilizers on the ground
to be varied or limited. Without using the size of the support pad, the force on the
ground can be limited. Using the size of the stabilizer pads, the pressure of the
stabilizers on the ground can be limited. Thus, the processor circuitry may be configured
to receive, from the remote-control device, information on a size of a stabilizer
pad of at least one support leg. The processor circuitry may be configured to adjust,
interpret or convert at least one force measurement associated with the at least one
support leg based on the size of the stabilizer pad. For example, when comparing the
at least one force measurement to the at least one force threshold, the respective
forces may be forces and force thresholds that are applied or defined with respect
to a unit of area on the ground. This way, the proposed concept can easily be adjusted
to differently-sized stabilizer pads and/or to requirements regarding the pressure
on the ground (instead of the force on the ground).
[0022] In the proposed concept, different levels of thresholds are used. For example, a
first threshold and a second threshold being different from the second threshold,
e.g., being higher than the first threshold, is used. For example, the first threshold
may be the user-defined threshold, and the second, higher threshold may be the security,
legal or regulatory threshold. Alternatively, the first threshold may be a pre-defined
fraction (e.g., at least 75%, 80%, or 90%) of the second threshold, which may be user-defined
threshold or a security, legal or regulatory threshold. In some cases, a third threshold
may be used in addition to the first and second threshold, being higher than the first
and second threshold. These thresholds may be distinguished, and different indications
may be provided depending on which threshold has been reached or surpassed. In other
words, the processor circuitry is configured to compare the force measurements to
the first and the second threshold. The processor circuitry is configured to provide
the control signal to control the indicator to exhibit a first indication behavior
if the force measurements indicate that a respective force exceeds (or reaches) the
first threshold and to control the indicator to exhibit a second indication behavior
if the force measurements indicate that the respective force exceeds (or reaches)
the second threshold. For example, the processor circuitry may be configured to compare
the force measurements to the third threshold and control the indicator to exhibit
a third indication behavior if the force measurements indicate that a respective force
exceeds (or reaches) the third threshold. This can be used to distinguish between
scenarios in which the operator has to use caution to proceed (first threshold) and
scenarios in which the operator has to cease operating the lifting device (second
threshold). This provides the operator with more fine-granular indications that help
improve operation of the lifting device by the operator.
[0023] As outlined above, the first and second (and third) indication behavior may be used
to information the operator as to which scenario the operator is operating in (e.g.,
normal operation, operate with caution, cede operations immediately). These can be
distinguished, using the indicator(s), using different means, such as using different
colors, different alarm tones, or different vibrations. For example, the first and
second (and third) indication may differ with respect to a color to be output by the
indicator (e.g., yellow and red). Alternatively, or additionally (if multiple indicators
are used), the first and second (and third) indication may differ with respect to
a vibrational force, speed or pattern to be output by the indicator. For example,
the vibrational force or speed used for the first indication may be lower than the
vibrational force or speed used for the second indication etc. Similarly, the vibrational
pattern used for the first indication may be less hectic or stressful than the vibrational
pattern used for the second indication etc. This way, the operator can sub-consciously
distinguish the different scenarios.
[0024] In some cases, one of the thresholds being used may be a security, legal or regulatory
threshold, or the operator may define a threshold that represents a maximal support
force the operator is comfortable with. In this case, if this threshold is surpassed,
the operation of the lifting device may be limited (in addition to the respective
indication being shown). In other words, the processor circuitry may be configured
to limit the speed of movement of the lifting device based on the comparison. Additionally,
or alternatively, the processor circuitry may be configured to limit a selection of
movements that can be performed by the lifting device based on the comparison. This
way, the safety of operating the lifting device may be improved.
[0025] In particular, the processor circuitry may be configured to compare the force measurements
to a first and a second threshold, and to limit a speed of movement of the lifting
device if the force measurements indicate that a respective force exceeds the first
threshold and to limit a selection of movements that can be performed by the lifting
device if the force measurements indicate that the respective force exceeds the second
threshold. Limiting the speed of movement can improve the safety of operation the
lifting device is mildly critical situations, as it decrease the speed at which the
measured support forces change, while limiting the selection of movements can ensure
that the support forces are not increased. This way, the safety of operating the lifting
device may be improved.
[0026] For example, the first threshold may be a user-defined threshold. The second threshold
may be a security threshold defined by the specifications of the support legs or of
the lifting device, e.g., a security, legal or regulatory threshold, or an absolute
maximum before complete stop. By distinguishing multiple thresholds, the user can
be made aware of mildly critical scenarios before reaching the thresholds defined
by the specifications of the support legs or of the lifting device, e.g., a security,
legal or regulatory threshold. This way, the operator can be made aware that he or
she is to use additional caution after having surpassed the user-defined threshold,
without the operation of the lifting device being limited due to having reached the
second threshold.
[0027] In some examples, the first threshold may be a pre-defined ratio or offset from a
user-defined threshold and the second threshold may be the user-defined threshold.
For example, the first threshold may be 75% of the second threshold, 80% of the second
threshold, or 90% of the second threshold. This way, the user does not have to input
multiple thresholds while distinguishing between the three scenarios (normal operation,
operating with caution, cede operations). In this case, the security threshold defined
by the specifications of the support legs or of the lifting device may be used as
a third threshold (being higher than the first and second threshold).
[0028] Another aspect of the present disclosure relates to a lifting device comprising the
control apparatus. Another aspect of the present disclosure relates to a system comprising
a carrier vehicle and the lifting device (comprising the control apparatus), with
the lifting device being mounted on the carrier vehicle.
[0029] Another aspect of the present disclosure relates to a corresponding method for a
lifting device. The method comprises receiving force measurements from force sensors
associated with support legs being used to stabilize the lifting device. The method
comprises comparing the force measurements to at least one force threshold. The method
comprises providing a control signal to a remote-control device to control at least
one indicator of the remote-control device based on the comparison. For example, the
method may comprise one or more additional features that have been discussed in connection
with the corresponding control apparatus. For example, the method may be performed
by the lifting device, e.g., by the control apparatus of the lifting device. Alternatively,
the method may be performed by the carrier vehicle, e.g., by a control apparatus of
the carrier vehicle.
[0030] Another aspect of the present disclosure relates to a computer program having a program
code for performing the method, when the computer program may be executed on a computer,
a processor, or a programmable hardware component.
[0031] Some aspects of the present disclosure relate to a remote-control device for controlling
a lifting device. For example, the remote-control device may be a portable device,
i.e., a device to be carried around by a user. For example, the remote-control device
may be a handheld device or a device carried by a user with the help of a neck strap.
For example, the remote-control device might not be a device that is permanently attached
to another device, such as a vehicle or the lifting device. The remote-control device
comprises an indicator, interface circuitry for communicating with a control apparatus
of the lifting device, and processor circuitry. The processor circuitry is configured
to receive, from the control apparatus, a control signal to control the indicator
of the remote-control device. The control signal is based on a comparison between
force measurements of force sensors associated with support legs being used to stabilize
the lifting device and at least one force threshold. The processor circuitry is configured
to control the indicator of the remote-control device based on the control signal.
By obtaining a control signal to control an indicator, the operator of the lifting
device can be supplied with valuable information on the current support force measured
for the support legs. To improve operation of the lifting device (and the support
legs) while the operator is using the remote-control device, the control signal is
provided to the remote-control device, to control the indicator of the remote-control
device, so that the operator becomes aware of the indication as he or she is controlling
the lifting device via the remote-control device.
[0032] For example, the indicator may comprise a display or a light-emitting diode. The
processor circuitry may be configured to display a color indicator representing the
comparison on the display or using the light-emitting diode. Visual indications provide
a means to provide precise information to the operator, e.g., using numbers to represent
the measured forces and the threshold(s). Different colors (e.g., in the user interface,
or when using the LEDs) can be used to let the operator take in the urgency of the
situation at a glance.
[0033] Additionally, or alternatively, the indicator may comprise a vibration motor. The
processor circuitry may be configured to control the vibration motor based on the
control signal. A vibration can be perceived by the operator even in noisy environments
and while having their eyes on the lifting device rather than the remote-control device,
thus improving the likelihood that the operator becomes aware of the indication.
[0034] For example, the remote-control device according to one may comprise a user interface.
The processor circuitry may be configured to obtain, via the user interface, an input
with respect to the at least one force threshold, and to provide the at least one
force threshold to the control apparatus based on the input. This way, a threshold
being used for the comparison can be input by the operator based on the scenario,
e.g., ground conditions, at hand.
[0035] Additionally, or alternatively, the processor circuitry may be configured to obtain,
via the user interface, an input with respect to a size of a stabilizer pad of at
least one support leg, and to provide the at least one force threshold and/or information
on the size of the stabilizer pad to the control apparatus based on the input. This
way, the control apparatus can be made aware of the size of the stabilizer pad and
can adjust its interpretation of the force measurements accordingly.
[0036] Some aspects of the present disclosure relate to a corresponding method for a remote-control
device for controlling a lifting device. The method comprises receiving, from a control
apparatus for controlling the lifting device, a control signal to control an indicator
of the remote-control device. The control signal is based on a comparison between
force measurements of force sensors associated with support legs being used to stabilize
the lifting device and at least one force threshold. The method comprises controlling
the indicator of the remote-control device based on the control signal. For example,
the method may comprise one or more additional features that have been discussed in
connection with the corresponding remote-control device. For example, the method may
be performed by the remote-control device. Alternatively, the method may be performed
by a mobile device, such as a tablet computer, being used to control the lifting device
and/or the carrier vehicle.
[0037] Another aspect of the present disclosure relates to a computer program having a program
code for performing the method, when the computer program may be executed on a computer,
a processor, or a programmable hardware component.
Brief description of the Figures
[0038] Some examples of apparatuses and/or methods will be described in the following by
way of example only, and with reference to the accompanying figures, in which
- Fig. 1
- shows a schematic drawing of side view a lifting device mounted on a carrier vehicle;
- Fig. 2
- shows a schematic drawing of a top view of a lifting device mounted on a carrier vehicle;
- Fig. 3a
- shows a block diagram of an example of a control apparatus for a lifting device;
- Fig. 3b
- shows a flow chart of an example of a method for controlling a lifting device;
- Fig. 4a
- shows a block diagram of an example of a remote-control device for controlling a lifting
device;
- Fig. 4b
- shows a flow chart of an example of a method for a remote-control device for controlling
a lifting device;
- Figs. 5a to 7b
- show flow charts of example flows for controlling at least one indicator representing
a support force at at least one support leg of a lifting device or carrier vehicle;
- Fig. 8a
- shows a user interface screen for activating or selecting a stabilizer mode;
- Fig. 8b
- shows a user interface screen for setting an input value;
- Figs. 9a to 9c
- show user interface screens for controlling an operation of support legs of a carrier
vehicle; and
- Fig. 10
- shows a user interface screen for monitoring a support force while operating a lifting
device.
Detailed Description
[0039] Some examples are now described in more detail with reference to the enclosed figures.
However, other possible examples are not limited to the features of these embodiments
described in detail. Other examples may include modifications of the features as well
as equivalents and alternatives to the features. Furthermore, the terminology used
herein to describe certain examples should not be restrictive of further possible
examples.
[0040] Throughout the description of the figures same or similar reference numerals refer
to same or similar elements and/or features, which may be identical or implemented
in a modified form while providing the same or a similar function. The thickness of
lines, layers and/or areas in the figures may also be exaggerated for clarification.
[0041] When two elements A and B are combined using an "or", this is to be understood as
disclosing all possible combinations, i.e. only A, only B as well as A and B, unless
expressly defined otherwise in the individual case. As an alternative wording for
the same combinations, "at least one of A and B" or "A and/or B" may be used. This
applies equivalently to combinations of more than two elements.
[0042] If a singular form, such as "a", "an" and "the" is used and the use of only a single
element is not defined as mandatory either explicitly or implicitly, further examples
may also use several elements to implement the same function.
If a function is described below as implemented using multiple elements, further examples
may implement the same function using a single element or a single processing entity.
It is further understood that the terms "include", "including", "comprise" and/or
"comprising", when used, describe the presence of the specified features, integers,
steps, operations, processes, elements, components and/or a group thereof, but do
not exclude the presence or addition of one or more other features, integers, steps,
operations, processes, elements, components and/or a group thereof.
[0043] Fig. 1 shows a schematic drawing of side view a lifting device 110 (a knuckle boom
crane) mounted on a carrier vehicle 120. The carrier vehicle 120 is parked on an inclined
base (angle of inclination approximately 5° in the illustration) with a lifting device
110 in the form of a knuckle boom crane arranged on it. The carrier vehicle 120 has
a support system with four support legs 130a, 130b (partially concealed, see also
Fig. 2) and a control unit 140 arranged on the carrier vehicle for actuating the drives
of the support legs 130a-130b based on a support leg control signal. In Fig. 1, the
parked carrier vehicle 120 has been aligned to the horizontal after being supported
by the support legs 130a-130b on the surface. The inclination relative to the horizontal
is essentially 0° in the illustration. It can be seen that at least one wheel of the
carrier vehicle 120 has remained on the ground, i.e. the carrier vehicle 120 has not
been completely lifted by the support legs 130a-130b. In contrast to the illustration,
the carrier vehicle 120 can also be completely raised. While Fig. 1 shows an inclination
of the ground along a center axis of the carrier vehicle 120 spanning the carrier
vehicle from back to front (or front to back), the support legs can also be used to
compensate for an inclination along other axes of the carrier vehicle 120, e.g., an
inclination along an axis that is perpendicular to the center axis.
[0044] Fig. 2 shows a schematic drawing of the top view of a lifting device 210 mounted
on a carrier vehicle 220. For example, the lifting device 210, carrier vehicle 220
and support legs 230a-230d of Fig. 2 may be implemented similar to the lifting device
110, carrier vehicle 120 and support legs 130a-130b of Fig. 1. As shown, the carrier
vehicle has horizontally adjustable support arms on which the support legs 230a-230d
are arranged.
[0045] The proposed concept is based on using measured support forces measured by force
sensors associated with the respective support legs to provide an indication to an
operator of the lifting devices. In general, a support force is the force exerted
by the support legs, also known as outriggers, to stabilize the lifting device (e.g.,
the crane) during operation. This force counteracts the weight and movement of the
load being lifted, maintaining balance and preventing the vehicle from tipping over.
The support force of support legs of a vehicle-mounted lifting device can be measured
using load cells or pressure sensors integrated into the support legs. These devices
monitor the force exerted by each leg and provide real-time data to ensure stability
and safe operation. Accordingly, the support legs 130a-b, 230a-d shown in Fig. 1 and
2 may include force sensors 36 (shown in Fig. 3) being configured to determine, e.g.,
substantially in real-time, the support force of the respective legs. These force
measurements are provided to a control apparatus 30 (also shown in Fig. 3) for controlling
the lifting device.
[0046] Fig. 3a shows a block diagram of an example of a control apparatus 30 for a lifting
device 300, e.g., for the lifting device 110, 210 of Figs. 1 and/or 1b. Fig. 3a further
shows the lifting device 300 comprising the control apparatus 30. For example, the
lifting device 300 may be implemented similar to the lifting device 110, 210 of Figs.
1 and/or 2. For example, as shown in Fig. 1 and 2, the lifting device 110, 120 (e.g.,
comprising the control apparatus 30) may be mounted on a carrier vehicle 120, 220
and form a system together with the carrier vehicle.
[0047] In general, the lifting device 110, 210, 300 may, for example, be a crane (e.g. a
loader crane) or an elevating work platform (e.g. a crane with a lifting platform).
The lifting device may be a knuckle boom crane or a stiff boom crane. Cranes having
only one boom may also be called stiff boom cranes since they do not exhibit multiple
booms that can change their orientation with respect to each other. In the event of
cranes having multiple booms, a knuckle can be used to connect the different booms
to one another so as to enable them to change their relative orientation, by bending
about an axis defined by the knuckle. Cranes having at least two booms connected by
a knuckle or hinge offer an additional degree of freedom as compared to stiff boom
cranes and may be called knuckle-boom cranes. The booms can be connected by hydraulic
cylinders across the knuckle to cause the rotation.
[0048] The lifting device may have a crane arm system (e.g. also called crane arm or boom)
with arms (e.g. also called crane arm segments) with a variable geometry, whereby
the arms of the crane arm system can be moved in relation to each other by at least
one actuator in the direction of at least one degree of freedom.
[0049] The movements of a degree of freedom can be performed by an actuator corresponding
to the degree of freedom. For example, two arms that are pivotably mounted to each
other can be pivoted relative to each other by an actuator. Two arms mounted so that
they can be translationally moved relative to each other can, for example, be translationally
moved relative to each other by an actuator.
[0050] The lifting device can be moved by control of actuators by issuing operating commands
by an operator or user, preferably via a suitable user interface (e.g. a remote control).
For example, individual actuators of the lifting device can be specifically controlled
by corresponding control commands on the basis of operating commands from an operator.
[0051] The degrees of freedom of the crane arm system can basically comprise angles of arms
of the crane arm system to each other or with respect to a horizontal or vertical
axis and lengths of arms that can be changed in length. The actuators can be implemented
by hydraulic cylinders or electric drives.
[0052] Control commands can generally be issued by the control apparatus 30 in the form
of control signals, which may contain control pulses with an amplitude and a pulse
duration, whereby control pulses can be used, for example, to switch electric drives
and/or control valves for the hydraulic supply of actuators of the lifting device.
[0053] In the proposed concept, the control apparatus is used to monitor, and optionally
control, the support legs 130a-b, 230a-d of the lifting device or carrier vehicle.
The control apparatus 30 comprises interface circuitry 32 and processor circuitry
34. The interface circuitry 32 is coupled with the processor circuitry 34. For example,
the processor circuitry 34 may be configured to provide the functionality of the control
apparatus 30, e.g., in conjunction with the interface circuitry 32 (for exchanging
information with other entities, such as a remote-control device 40 shown in Fig.
4, with one or more force sensors 36 (e.g., directly or via the control apparatus
of the carrier vehicle), or with one or more indicators 38). For example, the processors
circuitry 34 may be configured to execute machine-readable instructions to provide
its functionality. For example, the control apparatus 30 may comprise the machine-readable
instructions being executed by the processor circuitry 34.
[0054] The control apparatus 30 comprises interface circuitry 32. For example, the interface
circuitry 32 may be used for receiving signals from sensors, a control panel, a control
apparatus of a carrier vehicle and/or a remote-control device 40 through a wireless
or wired connection. For example, the interface circuitry 32 may be used for transmitting
signals to actuators, drivers, controllers of actuators, a control panel, a control
apparatus of a carrier vehicle and/or a remote-control device through a wireless or
wired connection. For example, the interface circuitry 32 may comprise a single universal
input and/or output interface or various different input and/or output interfaces
(e.g. a wireless input and/or output interface to be connected to a remote control
and wired input and/or output interfaces for different sensors, actuators or drivers
or controllers of actuators) for different data sources.
[0055] In embodiments the processor circuitry 34 may be implemented using one or more processing
units, one or more processing devices, any means for processing, such as a processor,
a computer or a programmable hardware component being operable with accordingly adapted
software. In other words, the described function of the processor circuitry 34 may
as well be implemented in software, which is then executed on one or more programmable
hardware components. Such hardware components may comprise a general-purpose processor,
a Digital Signal Processor (DSP), a micro-controller, etc.
[0056] The processor circuitry 34 is configured to receive, via the interface circuitry
32, force measurements from force sensors 36 associated with the support legs (e.g.,
support legs 130a-b, 230a-d of Figs. 1 and/or 2) being used to stabilize the lifting
device. The processor circuitry 34 is configured to compare the force measurements
to at least one force threshold. The processor circuitry 34 is configured to provide,
via the interface circuitry, a control signal to control at least one indicator 38
based on the comparison. The process of receiving the force measurements, comparing
the force measurements to at least one force threshold and providing the control signal
may be repeated over and over again, e.g., periodically (e.g., every 50 ms, every
100 ms, every 200 ms, every 500 ms, or every second) or when new force measurements
are received.
[0057] Fig. 3b shows a flow chart of an example of a corresponding method for controlling
the lifting device 110, 120, 300. The method comprises receiving 310 force measurements
from force sensors associated with support legs being used to stabilize the lifting
device. The method comprises comparing 320 the force measurements to at least one
force threshold. The method comprises providing 330 a control signal to control at
least one indicator based on the comparison. For example, the method may comprise
one or more additional features that are described in connection with the control
apparatus of Fig. 3a and in connection with the examples of Fig. 5 to 10.
[0058] In many cases, a remote-control device, e.g., remote-control device 40 of Fig. 4,
is used by an operator, to control the lifting device. For example, the remote-control
device 40 may be used to operate the lifting device by sending (wireless) control
signals to the crane's control apparatus 30. The control apparatus 30 interprets these
signals and directs the lifting device's motors and other components to perform specific
actions like lifting, lowering, or rotating the load. This allows the operator to
control the lifting devices from a safe distance.
[0059] In the proposed concept, the remote-control device can be provided with an indicator.
Fig. 4a shows a block diagram of an example of a remote-control device 40 for controlling
a lifting device 110, 210, 300 that comprises one or more indicators 46, 48. The remote-control
device 40 further comprises interface circuitry 42 for communicating with the control
apparatus 30 of the lifting device, and processor circuitry 44 that is coupled with
the interface circuitry 42 and the indicator 46, 48 (e.g., via the interface circuitry
42). The interface circuitry 42 is coupled with the processor circuitry 44. For example,
the processor circuitry 44 may be configured to provide the functionality of the control
apparatus 40, e.g., in conjunction with the interface circuitry 42 (for exchanging
information with other entities, such as the control apparatus 30 of the lifting device
300). For example, the processors circuitry 44 may be configured to execute machine-readable
instructions to provide its functionality. For example, the control apparatus 40 may
comprise the machine-readable instructions being executed by the processor circuitry
44. For example, the remote-control device 40 may comprise a user interface 48 (with
a display) that can be used as an indicator, and/or the remote-control device 40 may
comprise an indicator 46 that is separate from the display, such as one or more LEDs
and/or a vibration motor.
[0060] The interface circuitry 42 may correspond to one or more inputs and/or outputs for
receiving and/or transmitting information, which may be in digital (bit) values according
to a specified code, within a module, between modules or between modules of different
entities. For example, the interface circuitry 42 may comprise interface circuitry
configured to receive and/or transmit information. The processor circuitry 44 may
be implemented using one or more processing units, one or more processing devices,
any means for processing, such as a processor, a computer or a programmable hardware
component being operable with accordingly adapted software. In other words, the described
function of the processor circuitry 44 may as well be implemented in software, which
is then executed on one or more programmable hardware components. Such hardware components
may comprise a general-purpose processor, a Digital Signal Processor (DSP), a micro-controller,
etc.
[0061] The processor circuitry 44 of the remote-control device 40 is configured to receive
from the control apparatus 30 and via the interface circuitry 42, the control signal
to control the indicator 46, 48 of the remote-control device. The control signal is
based on a comparison between force measurements of force sensors 36 associated with
the support legs being used to stabilize the lifting device and at least one force
threshold. The processor circuitry 44 of the remote-control device 40 is configured
to control the indicator of the remote-control device based on the control signal.
[0062] Fig. 4a further shows a system comprising the control apparatus 30 and the remote-control
device 40. For example, the system may comprise the lifting device with the control
apparatus 30.
[0063] Fig. 4b shows a flow chart of an example of a corresponding method for a remote-control
device for controlling a lifting device. The method comprises receiving 410, from
a control apparatus for controlling the lifting device, the control signal to control
an indicator of the remote-control device. The control signal is based on a comparison
between force measurements of force sensors associated with support legs being used
to stabilize the lifting device and at least one force threshold. The method comprises
controlling 420 the indicator of the remote-control device based on the control signal.
For example, the method may be performed by the remote-control device 40 of Fig. 4a.
Features introduced in connection with the remote-control device 40 of Fig. 4a may
likewise be introduced into the corresponding method of Fig. 4b.
[0064] More details and aspects of the control apparatus 30, the corresponding method and
a corresponding computer program, and of the remote-control device 40, the corresponding
method and a corresponding computer program are mentioned in connection with the proposed
concept or one or more examples described above or below (e.g. Fig. 1 to 2, 5a to
10). The control apparatus 30, remote-control device 40, and the corresponding methods
and computer programs may comprise one or more additional optional features corresponding
to one or more aspects of the proposed concept or one or more examples described above
or below.
[0065] In the following, the functionality of the control apparatus 30 of Fig. 3a and of
the remote-control device 40 of Fig. 4 will be explained in more detail together with
reference to the examples given in connection with Figs. 5a to 10.
[0066] Some lifting devices or carrier vehicles have a force stabilization function, which
can be used to stabilize the carrier vehicle or lifting device based on the pressure
in the stabilizers (support legs). In addition to automatic stabilization, the pressure
in the crane stabilizers can be output as a percentage of their maximum tolerable
force, rather than showing the exact force or pressure. Similarly, some lifting devices
or carrier vehicles have a frame protection system (FPS) that is used to protect the
frame of the carrier vehicle or lifting devices based on the pressure in the front
stabilizers. Again, the FPS function can be used to show the pressure in the front
stabilizers as a percentage. In both cases, the pressure in the stabilizers is measured,
which enables a determination of the support force.
[0067] The proposed concept is based on the insight that it would be beneficial, for the
operators, to view the actual force exerted by the stabilizers. The proposed concept,
in the following also denoted Support Force Limitation (SFL) function allows the operator
to see the real-time force of the stabilizers. For example, the operator may input
a specific amount of force to the crane via remote control. If the actual stabilizer
force exceeds this input, the operator receives a notification. To enable SFL, the
lifting device or carrier vehicle may comprise sensors to measure the pressure or
support force. This applies to lifting devices that support the force stabilization
function, as lifting devices supporting the force stabilization function use stabilizers
with pressure sensors. The hardware used for the force stabilization function is thus
used by the SFL software discussed in the present disclosure.
[0068] The Support Force Limitation function may enable the operator to view the real-time
force in the stabilizers and input a specific force. If the real-time force of the
stabilizers exceeds this input amount, notifications may be sent to the operator.
These notifications may include vibrations from the remote control, changes in the
remote control's lights to yellow and red, and flashing lights on the stabilizers,
for example.
[0069] Examples of the use of the SFL function are now discussed in the context of the flow
charts of Figs. 5a to 7b. Figs. 5a to 7b show flow charts of example flows for controlling
at least one indicator representing a support force at at least one support leg of
a lifting device or carrier vehicle. In Figs. 5a to 7b, user input is denoted by thin,
solid lines, while software functions (e.g., performed by the control apparatus 30
of Fig. 3a) are denoted by thick, dashed lines. Figs. 5a and 5b show two portions
of the same flow, as do Figs. 6a and 6b and Figs. 7a and 7b, respectively.
[0070] The flow presented in Figs. 5a and 5b starts at 501 with switching on the SFL function,
and, at 502, saving the SFL status. Concurrently, at 503, the system (e.g., the control
apparatus 30) boots up. If SFL is enabled, the system checks if all stabilizers and
the crane are in a transport position. If yes, at 504, the user defines a new input
value (threshold), e.g., using the remote control, and, at 505, the system saves a
new value. In other words, with respect to the control apparatus 30 of Fig. 3a, the
processor circuitry of the control apparatus 30 may be configured to receive, from
the remote-control device 40, the at least one force threshold. Accordingly, with
respect to the remote-control device 40 of Fig. 4a, the remote-control device may
comprise a user interface 48, with the processor circuitry of the remote-control device
being configured to obtain, via the user interface, an input with respect to the at
least one force threshold, and to provide the at least one force threshold to the
control apparatus 30 based on the input. In other words, the user (operator) inputs
the input value (the input with respect to the at least one force threshold) at the
remote-control device 40, which transmits the input value to the control apparatus
30.
[0071] In some cases, the support legs can be used with different types of stabilizer pads,
which are used as "feet" of the support legs. Depending on their size, the force measurements
may be implemented differently, as the overall support force is distributed over the
area covered by the stabilizer pad. In other words, depending on the size of the support
pad, the force applied by square centimeter square changes, while the overall support
force stays the same. As regulations regarding the maximally allowed support force
are generally defined for a pre-defined area (e.g., per m
2, per ft
2 or per cm
2), the size of the stabilizer pads may be used to adjust (e.g., scale), interpret
or convert (into a force measurement per unit of area) the force measurements. Similar
to the at least one force threshold, the size of the stabilizer pads may be input
via the remote control device. Accordingly, the processor circuitry of the remote
control device may be configured to obtain, via the user interface, an input with
respect to the size of a stabilizer pad of at least one support leg, and to provide
information on the size of the stabilizer pad to the control apparatus based on the
input. For example, the size (e.g., radius, diameter, x-y dimensions or area) may
be input numerically, or may be selected from a set of pre-defined sizes. The control
apparatus can then use the information on the size of the support legs to process
the force measurements. In other words, the processor circuitry of the control apparatus
may be configured to receive, from the remote-control device, the information on a
size of a stabilizer pad of at least one support leg, and to adjust, interpret or
convert the at least one force measurement associated with the at least one support
leg based on the size of the stabilizer pad.
[0072] If the stabilizers and the crane are not in a transport position, at 506, the user
may indicate to use the last saved input value, and, at 507, the system may use the
saved value. At 508, the system measures each stabilizer force. The system then compares
the measured values with an overload limit (e.g., a second threshold), and if the
measured values exceed the overload limit, at 509, the system may stop all dangerous
movements and return to measuring the stabilizer force at 508. If the measured values
do not exceed the overload limit, at 510, the system may show the force values on
a display 48 of the remote-control device, e.g., by transmitting the control signal
to the remote-control device 40. At 511, the system may send the measured force to
a telematics module (for processing date, time, GPS (Global Positioning System), force,
size of support input etc.). The system may compare the measured values with the input
value. If the measured values are less than 80% of the input value, at 512, the light
on the remote-control device stay green, and, at 513, lights at the stabilizers are
permanently on. If the measured values are between 80% of the input value and less
than 100% of the input value, at 514, the lights on the remote-control device turn
to orange, at 515 the remote-control device vibrates, at 516, the stabilizer lights
start blinking, and at 517, the speed of the crane is reduced. If the measured values
are larger than 100% of the input value, at 518, the lights on the remote-control
device turn to red, at 519 the remote-control device vibrates, at 520, the stabilizer
lights blink faster, and at 521, all dangerous movements of the crane are stopped.
[0073] This flow illustrates the features of the control apparatus 30 and remote-control
device 40. It is evident from blocks 510 and 512-521 that the indicator that is based
on the comparison of the force measurements and the at least one thresholds may be
provided both to the remote-control device 40 (see blocks 510, 512, 514, 515, 518,
519) and to an optical or acoustic system of the lifting device or carrier vehicle
(blocks 513, 516, 520). In addition, the operation of the lifting device may be slowed
(block 517) or limited (block 521).
[0074] In various examples, the remote-control device is used to provide the indication
to the user. Accordingly, the processor circuitry of the control apparatus may be
configured to provide the control signal to the remote-control device 40.
[0075] At the remote-control device, the indication may be provided visually, e.g., via
lights (e.g., LEDs) or via a display (e.g., a display used to provide the user interface).
In particular, the processor circuitry of the control apparatus may be configured
to provide the control signal to the remote-control device to trigger a visual indicator
representing the comparison to be displayed (e.g., using the LEDs or the display)
by the remote-control device. Accordingly, the indicator of the remote-control device
may comprise a display and/or at least one LED, with the processor circuitry being
configured to display the indication using the at least one LED or the display. In
particular, the processor circuitry may be configured to provide a color indicator
representing the comparison on the display or using the light-emitting diode. In the
example given in Figs. 5a and 5b, three different color indicators are given - green
(box 512) in the normal operation case, yellow (box 514) in the "operate with caution"
case, and red (box 518) in the "cede operation" case. These color indicators may be
output by LEDs on the remote-control device or using the display of the remote-control
device (as shown in Figs. 9a to 9c and 10). For example, for each of the support legs,
a separate color indicator may be provided (see Figs. 9a to 9c and 10). Alternatively,
the color indicator representing the "worst case" (e.g., the highest percentage of
the user input in the context of Figs. 5a and 5b) may be used, e.g., if only a single
color indicator is provided that is representative of all comparisons.
[0076] Additionally, or alternatively, the indication may be provided using vibration. For
example, the indicator of the remote-control device may comprise a vibration motor,
with the processor circuitry of the remote-control device being configured to control
the vibration motor based on the control signal. Accordingly, the processor circuitry
of the control apparatus may be configured to provide the control signal to the remote-control
device to trigger a vibration at the remote-control device. For example, as shown
in Fig. 5b, in the "normal operation" case, no vibration may be caused, in the "operate
with caution" case, a vibration with a lower or slower vibrational force, pattern
or speed may be used, and in the "cede operation" case, a vibration with a higher
or faster vibrational force, pattern or speed may be used. Alternatively, in both
the "operate with caution" and the "cede operation" case, the same vibrational force,
pattern or speed may be used.
[0077] Another modality for providing the indication to the operator is to use an optical
system or acoustic system at the lifting device or at the carrier vehicle. Accordingly,
the processor circuitry may be configured to provide the control signal to an optical
system or acoustic system of the lifting device or to an optical system or acoustic
system of a carrier vehicle hosting the lifting device. In particular, as shown in
boxes 513, 516 and 520 of Fig. 5b, lights may be placed on the stabilizers (support
legs) as optical system, to indicate the comparison between the measured forces and
the at least one force threshold. Additionally, or alternatively, lights or a display
may be arranged at a status board mounted on the lifting device or carrier vehicle.
For example, similar to the example with respect to the remote-control device, color
indicators may be used to display an indication representing the comparison. Alternatively,
a blinking rate (permanently on or off, slower blinking, faster blinking, as shown
in boxes 513, 516, 520) of the optical system (i.e., lights) may be used as indication
of the comparison. Furthermore, in addition or instead of the optical system, an acoustic
system may be used (e.g., loudspeakers). For example, no acoustic signal might be
provided in the "normal operation" case, a first lower sound or lower repetition rate
of an alarm sound might be provided in the "operation with caution" case, and a second
higher sound or higher repletion rate of an alarm sound might be provided in the "cede
operation" case etc.
[0078] The proposed concept is based on the comparison of the measured forces with at least
one (operator-defined, user-defined) threshold. In particular, the comparison may
be performed separately for each of the support legs. In other words, the force measurements
may comprise, for two or more support legs, separate force measurements being taken
by a force sensor associated with the respective support leg. These force measurements
may be compared separately to the at least one threshold. For example, the processor
circuitry may be configured to compare the force measurements separately to the at
least one force threshold. The same threshold or thresholds may be used for comparison
for each of the support legs, or a different threshold or different thresholds may
be used. In other words, the processor circuitry may be configured to compare the
force measurements to the same force threshold, or to compare the force measurements
to support leg-specific thresholds.
[0079] In the example of Figs. 5a and 5b, it is not specified whether the indications are
provided on a per-support leg basis or whether the indication(s) is/are provided for
the entirety of the support legs (without showing indications for the separate support
legs). In the former case, the processor circuitry may be configured to provide the
control signal such, that, if the comparison of a force measurement for a support
leg reaches or surpasses the threshold for the support leg, the at least one indicator
may be controlled to indicate that the force measurement for the support leg (i.e.,
this particular support leg) has reached or surpassed the threshold. Accordingly,
separate indicators or indicator regions may be used to provide indications for the
individual support legs. In the latter case, one indication (e.g., per modality) may
be provided, even if multiple indicators are used (e.g., at the support legs). For
example, the processor circuitry of the control apparatus may be configured to provide
the control signal such, that, if the comparison of a force measurement for a support
leg reaches or surpasses the threshold for the support leg, the at least one indicator
is controlled to indicate, at an indicator portion related to at least two support
legs, that the force measurement for at least one support leg has reached or surpassed
the threshold. In other words, if the measured force for one of the support legs (but
not the others) reaches or surpasses a threshold, the indicator portions for all of
the support legs may be changed, e.g., according to the highest force measurement.
For example, if the support force of one support leg reaches the respective threshold,
all light indicators may start to blink with the same indication sequence. Alternatively,
if the support force of one support leg reaches the respective threshold, the indication
sequence on each leg may be different. For example, the closer the support force of
a leg is to the respective threshold, the quicker the lights may blink (which may
differ between countries). In other words, the processor circuitry of the control
apparatus may be configured to provide the control signal such, that a blinking rate
of a light indicator (of the remote-control device or of a light (LED) mounted to
the lifting device or carrier vehicle (e.g., mounted to a support leg) is based on
a difference between the support force indicated by the force measurement of the respective
leg and the at least one threshold. For example, a smaller difference may result in
a higher blinking frequency than a larger difference.
[0080] In the example shown in Figs. 5a and 5b, several different thresholds are used. For
example, in Figs. 5a and 5b, a user input (a single threshold) is obtained, and another
threshold (80% of the user input) is derived from the user input, resulting in a first
(lower) threshold (80% of the user input) and in a second (higher) threshold (100%
of the user input). In other words, the first threshold may be a pre-defined ratio
(80%) or offset (e.g., a pre-defined amount of kN) from a user-defined threshold and
the second threshold may be the user-defined threshold. Alternatively, the first threshold
may be a user-defined (operator-defined) threshold, and the second threshold may be
a security threshold defined by the specifications of the support legs or of the lifting
device (e.g., a security, legal or regulatory threshold).
[0081] As a result, the force measurements may be compared to at least two thresholds (i.e.,
the first and the second threshold). Depending on the comparison, different indications
may be triggered, as shown in Fig. 5b. In other words, the processor circuitry may
be configured to compare the force measurements to a first and a second threshold,
and to provide the control signal to control the indicator to exhibit a first indication
behavior if the force measurements indicate that a respective force exceeds the first
threshold and to control the indicator to exhibit a second indication behavior if
the force measurements indicate that the respective force exceeds the second threshold.
In Fig. 5b, the first indication behavior is provided if the measured force is at
least 80% and below 100% of the user input. The first indication behavior includes
the lights of the remote-control device turning orange (box 514), the remote-control
device vibrating (box 515) and the lights of the stabilizer lights starting to blink
(with a first slower pattern, box 516). The second indication behavior includes the
lights of the remote-control device turning red (box 518). The remote-control device
vibrating (e.g., with a higher vibrational force, with a more intense pattern or with
a higher speed, box 519), and the stabilizer lights blinking faster (box 520). In
other words, the first and second indication may differ with respect to a color to
be output by the indicator, with respect to a blinking pattern/speed, or with respect
to a vibrational force, speed or pattern to be output by the indicator.
[0082] In Fig. 5b, a third indication behavior is also shown, which is triggered, in this
case, when the measured force is below (each of) the thresholds). This third indication
behavior includes the lights of the remote-control device being green (box 512) and
the stabilizer lights being permanently on (box 513). Accordingly, the processor circuitry
of the control apparatus may be configured to provide the control signal to control
the indicator to exhibit the third indication behavior if the force measurements indicate
that the respective force is below or at most the first and second threshold.
[0083] In Fig. 5b, in addition to providing the indication representing the comparison,
the operation of the lifting device (or support legs) may be adjusted based on the
comparison. In particular, as shown in box 517, the processor circuitry of the control
apparatus may be configured to limit a speed of movement of the lifting device based
on the comparison. Additionally, or alternatively, as shown in box 521, the processor
circuitry may be configured to limit a selection of movements that can be performed
by the lifting device based on the comparison. In particular, as further shown in
Fig. 5b, the processor circuitry may be configured to limit a speed of movement of
the lifting device if the force measurements indicate that a respective force exceeds
the first threshold and to limit a selection of movements that can be performed by
the lifting device if the force measurements indicate that the respective force exceeds
the second threshold.
[0084] In some examples, as shown in Fig. 5a, the force measurements may additionally be
compared to a third threshold ("overload limit" in Fig. 5a). For example, the processor
circuitry of the control apparatus may be configured to stop all dangerous movements
if the force measurements (e.g., if one force measurement) reaches or surpasses the
third threshold.
[0085] At 522, the user may change between different crane modes (crane, stabilizers, radio
remote, workman basked) at the remote-control device. At 523, the system may use the
same SFL value and status. At 524, the user may switch off the SFL function. At 525,
the system may save the SFL status (ON/OFF). When the SFL is switched off, the flow
ends.
[0086] The flow of Figs. 6a and 6b is substantially similar to the flow of Fig. 5a and 5b,
with the flow of Figs. 6a and 6b lacking the check of whether the crane and the support
legs are in a transport position and with the flow of Figs. 6a and 6b lacking the
actions "limiting the speed of movement of the crane" and "stopping all dangerous
movements".
[0087] The flow presented in Figs. 6a and 6b starts at 601 with switching on the SFL function,
and, at 602, saving the SFL status. Concurrently, at 605, the system (e.g., the control
apparatus 30) boots up. If SFL is enabled, at 603, the user may define a new input
value (threshold), e.g., using the remote control, and, at 604, the system saves a
new value. Alternatively, at 607, the user may indicate to use the last saved input
value, and, at 608, the system may use the saved value.
[0088] At 609, the system measures each stabilizer force. The system then compares the measured
values with an overload limit (e.g., a second threshold), and if the measured values
exceed the overload limit, at 610, the system may stop all dangerous movements and
return to measuring the stabilizer force at 609. If the measured values do not exceed
the overload limit, at 611, the system may show the force values on a display 48 of
the remote-control device, e.g., by transmitting the control signal to the remote-control
device 40. At 612, the system may send the measured force to a telematics module (for
processing date, time, GPS (Global Positioning System), force, size of support input
etc.). The system may compare the measured values with the input value. If the measured
values are less than 80% of the input value, at 613, the light on the remote-control
device stays green, and, at 614, lights at the stabilizers are permanently on. If
the measured values are between 80% of the input value and less than 100% of the input
value, at 615, the lights on the remote-control device turn to orange, at 616 the
remote-control device vibrates, and at 617, the stabilizer lights start blinking.
If the measured values are larger than 100% of the input value, at 618, the lights
on the remote-control device turn to red, at 619 the remote-control device vibrates,
and at 620, the stabilizer lights blink faster.
[0089] At 621, the user may change between different crane modes (crane, stabilizers, radio
remote, workman basked) at the remote-control device. At 622, the system may use the
same SFL value and status. At 623, the user may switch off the SFL function. At 624,
the system may save the SFL status (ON/OFF). When the SFL is switched off, the flow
ends.
[0090] Figs. 7a and 7b show a flow that is similar to the flow of Fig. 6a and 6b, without
the user inputting a new input value or selecting the previously input value, and
with only the "raw" force measurements being provided (without comparison to an input
value, with the force measurements only being compared to the overload limit.
[0091] The flow presented in Figs. 7a and 7b starts at 701 with switching on the SFL function,
and, at 702, saving the SFL status. Concurrently, at 703, the system (e.g., the control
apparatus 30) boots up.
[0092] At 704, the system measures each stabilizer force. The system then compares the measured
values with an overload limit (e.g., a second threshold), and if the measured values
exceed the overload limit, at 705, the system may stop all dangerous movements and
return to measuring the stabilizer force at 704. If the measured values do not exceed
the overload limit, at 706, the system may show the force values on a display 48 of
the remote-control device, e.g., by transmitting the control signal to the remote-control
device 40. At 707, the system may send the measured force to a telematics module (for
processing date, time, GPS (Global Positioning System), force, size of support input
etc.).
[0093] At 708, the user may change between different crane modes (crane, stabilizers, radio
remote, workman basked) at the remote-control device. At 709, the system may use the
same SFL value and status. At 710, the user may switch off the SFL function. At 711,
the system may save the SFL status (ON/OFF). When the SFL is switched off, the flow
ends.
[0094] As outlined in connection with Figs. 3a to 7b, in some cases, the indication may
be provided via a display of the remote-control device 40, and the at least one threshold
may be input via the user interface (e.g., touchscreen display) of the remote-control
device 40. In Figs. 8a to 10, various user interface screens are provided that illustrate
this functionality.
[0095] Fig. 8a shows a user interface screen for activating or selecting a stabilizer mode.
When the operator activates the SFL functionality, the comparisons between the measured
force values and the at least one threshold and the provision of the control signal
may be started.
[0096] Fig. 8b shows a user interface screen for setting an input value. This input value
may be used to set a threshold, e.g., the first and second threshold (with the first
threshold being a ratio or offset from the user input and the second threshold being
the user input), or the first threshold, with the second threshold being a pre-defined
threshold (security, legal, regularity or pre-defined threshold for the support legs).
[0097] Figs. 9a to 9c show user interface screens for controlling an operation of support
legs of a carrier vehicle. In Fig. 9a, using touchscreen buttons 900, vertical movement
of the front support legs 910a, 910b can be activated. The measured force values are
displayed next to the front support legs 910a, 910b. Color indicators (yellow, red,
green) are used per support leg, to identify a match between the support legs and
the touchscreen buttons. The user input (SFL) value 920 (threshold) is displayed on
top.
[0098] In Fig. 9b, using touchscreen buttons 900, vertical and horizontal movement of the
back support legs 910c, 910d can be activated, with illustration 930 showing the horizontal
extension of the back support legs. The measured force values are displayed next to
the back support legs 910c, 910d. Color indicators (red, green) are used per support
leg, to identify a match between the support legs and the touchscreen buttons. The
user input (SFL) value 920 (threshold) is displayed on top.
[0099] In Fig. 9c, using touchscreen buttons 900, vertical and horizontal movements of the
side support legs 910e to 910h can be controlled. Color indicators are used per side
support leg (along the horizontal extension of the respective support legs (which
is also indicated in the user interface), to identify a match between the support
legs and the touchscreen buttons. Next to the front, back and side support legs 910a-910h,
the measured force values are displayed. In addition, color indicators (red, yellow
and green) are used as color indicators at the circular portions of the respective
support legs, to indicate the comparison between the force measurements and two thresholds
(user input value 920 of 50 kN, 80% of the user input value). Support legs 910b, 910d,
910h at 10 kN, 21 kN and 28 kN, respectively, are shown in green, support legs 910c,
910f and 910g at 42 kN, 45 kN, and 45 kN, respectively are shown in yellow (as the
measured support force is larger than 80% of the user input value), and support legs
910a, 910e at 50 kN each are shown in red (as the measured support force has reached
100% of the user input). In the middle, at 940, the center of gravity (and deviation
from a base center of gravity) is shown.
[0100] Fig. 10 shows a user interface screen for monitoring a support force while operating
a lifting device. The user interface screen of Fig. 10 is similar to the screen shown
in Fig. 9c, without the touchscreen buttons (and corresponding color indicators) for
controlling operation of the support legs. Next to the front, back and side support
legs 1010a-910h, the measured force values are displayed. In addition, color indicators
(red, yellow and green) are used as color indicators at the circular portions of the
respective support legs, to indicate the comparison between the force measurements
and two thresholds (user input value 1020 of 50 kN, 80% of the user input value).
Support legs 1010b, 1010d, 1010h at 10 kN, 21 kN and 28 kN, respectively, are shown
in green, support legs 1010c, 1010f and 1010g at 42 kN, 45 kN, and 45 kN, respectively
are shown in yellow (as the measured support force is larger than 80% of the user
input value), and support legs 1010a, 1010e at 50 kN each are shown in red (as the
measured support force has reached 100% of the user input). In the middle, at 1040,
the center of gravity (and deviation from a base center of gravity) is shown.
[0101] In the following, some examples of the proposed concept are presented:
An example (e.g., example 1) relates to a control apparatus (30) for a lifting device
(110, 210, 300), the control apparatus comprising interface circuitry (32) and processor
circuitry (34), wherein the processor circuitry is configured to receive, via the
interface circuitry, force measurements from force sensors (36) associated with support
legs (130a, 130b, 230a, 230b, 230c, 230d) being used to stabilize the lifting device,
compare the force measurements to at least one force threshold, and provide, via the
interface circuitry, a control signal to control at least one indicator (38, 46, 48)
based on the comparison.
[0102] Another example (e.g., example 2) relates to a previous example (e.g., example 1)
or to any other example, further comprising that the processor circuitry is configured
to provide the control signal to a remote-control device (40).
[0103] Another example (e.g., example 3) relates to a previous example (e.g., example 2)
or to any other example, further comprising that the processor circuitry is configured
to provide the control signal to the remote-control device to trigger a vibration
at the remote-control device.
[0104] Another example (e.g., example 4) relates to a previous example (e.g., one of the
examples 2 or 3) or to any other example, further comprising that the processor circuitry
is configured to provide the control signal to the remote-control device to trigger
a visual indicator representing the comparison to be displayed by the remote-control
device.
[0105] Another example (e.g., example 5) relates to a previous example (e.g., one of the
examples 1 to 4) or to any other example, further comprising that the processor circuitry
is configured to provide the control signal to an optical system or acoustic system
of the lifting device or to an optical system or acoustic system of a carrier vehicle
hosting the lifting device.
[0106] Another example (e.g., example 6) relates to a previous example (e.g., one of the
examples 1 to 5) or to any other example, further comprising that the force measurements
comprise, for two or more support legs, separate force measurements being taken by
a force sensor associated with the respective support leg.
[0107] Another example (e.g., example 7) relates to a previous example (e.g., example 6)
or to any other example, further comprising that the processor circuitry is configured
to compare the force measurements separately to the at least one force threshold.
[0108] Another example (e.g., example 8) relates to a previous example (e.g., example 7)
or to any other example, further comprising that the processor circuitry is configured
to compare the force measurements to the same force threshold, or to compare the force
measurements to support leg-specific thresholds.
[0109] Another example (e.g., example 9) relates to a previous example (e.g., one of the
examples 7 or 8) or to any other example, further comprising that the processor circuitry
is configured to provide the control signal such, that, if the comparison of a force
measurement for a support leg reaches or surpasses the threshold for the support leg,
the at least one indicator is controlled to indicate that the force measurement for
the support leg has reached or surpassed the threshold.
[0110] Another example (e.g., example 10) relates to a previous example (e.g., one of the
examples 7 or 8) or to any other example, further comprising that the processor circuitry
is configured to provide the control signal such, that, if the comparison of a force
measurement for a support leg reaches or surpasses the threshold for the support leg,
the at least one indicator is controlled to indicate, at an indicator portion related
to at least two support legs, that the force measurement for at least one support
leg has reached or surpassed the threshold.
[0111] Another example (e.g., example 11) relates to a previous example (e.g., one of the
examples 1 to 10) or to any other example, further comprising that the processor circuitry
is configured to receive, from a remote-control device, the at least one force threshold.
[0112] Another example (e.g., example 12) relates to a previous example (e.g., one of the
examples 1 to 11) or to any other example, further comprising that the processor circuitry
is configured to receive, from the remote-control device, information on a size of
a stabilizer pad of at least one support leg, with the processor circuitry being configured
to adjust, interpret or convert at least one force measurement associated with the
at least one support leg based on the size of the stabilizer pad
[0113] Another example (e.g., example 13) relates to a previous example (e.g., one of the
examples 1 to 12) or to any other example, further comprising that the processor circuitry
is configured to compare the force measurements to a first and a second threshold,
and to provide the control signal to control the indicator to exhibit a first indication
behavior if the force measurements indicate that a respective force exceeds the first
threshold and to control the indicator to exhibit a second indication behavior if
the force measurements indicate that the respective force exceeds the second threshold.
[0114] Another example (e.g., example 14) relates to a previous example (e.g., example 13)
or to any other example, further comprising that the first and second indication differ
with respect to a color to be output by the indicator, or wherein the first and second
indication differ with respect to a vibrational force, speed or pattern to be output
by the indicator.
[0115] Another example (e.g., example 15) relates to a previous example (e.g., one of the
examples 1 to 14) or to any other example, further comprising that the processor circuitry
is configured to limit a speed of movement of the lifting device based on the comparison,
and/or wherein the processor circuitry is configured to limit a selection of movements
that can be performed by the lifting device based on the comparison.
[0116] Another example (e.g., example 16) relates to a previous example (e.g., one of the
examples 1 to 15) or to any other example, further comprising that the processor circuitry
is configured to compare the force measurements to a first and a second threshold,
and to limit a speed of movement of the lifting device if the force measurements indicate
that a respective force exceeds the first threshold and to limit a selection of movements
that can be performed by the lifting device if the force measurements indicate that
the respective force exceeds the second threshold.
[0117] Another example (e.g., example 17) relates to a previous example (e.g., one of the
examples 13, 14, or 16) or to any other example, further comprising that the first
threshold is a user-defined threshold and the second threshold is a security threshold
defined by the specifications of the support legs or of the lifting device.
[0118] Another example (e.g., example 18) relates to a previous example (e.g., one of the
examples 13, 14, or 16) or to any other example, further comprising that the first
threshold is a pre-defined ratio or offset from a user-defined threshold and the second
threshold is the user-defined threshold.
[0119] Another example (e.g., example 19) relates to a lifting device (110, 210) comprising
the control apparatus (30) according to one of the examples 1 to 18.
[0120] Another example (e.g., example 20) relates to a system comprising a carrier vehicle
(120, 220) and the lifting device (110, 210) according to example 19 mounted on the
carrier vehicle.
[0121] An example (e.g., example 21) relates to a remote-control device (40) for controlling
a lifting device (110, 210, 300), comprising an indicator (46, 48), interface circuitry
(42) for communicating with a control apparatus (30) of the lifting device, and processor
circuitry (44) configured to receive, from the control apparatus, a control signal
to control the indicator of the remote-control device, wherein the control signal
is based on a comparison between force measurements of force sensors associated with
support legs (130a, 130b, 230a, 230b, 230c, 230d) being used to stabilize the lifting
device and at least one force threshold, and control the indicator of the remote-control
device based on the control signal.
[0122] Another example (e.g., example 22) relates to a previous example (e.g., example 21)
or to any other example, further comprising that the indicator comprises a display
or a light-emitting diode, the processor circuitry being configured to display a color
indicator representing the comparison on the display or using the light-emitting diode.
[0123] Another example (e.g., example 23) relates to a previous example (e.g., one of the
examples 21 or 22) or to any other example, further comprising that the indicator
comprises a vibration motor, the processor circuitry being configured to control the
vibration motor based on the control signal.
[0124] Another example (e.g., example 24) relates to a previous example (e.g., one of the
examples 21 to 23) or to any other example, further comprisinga user interface (48),
with the processor circuitry being configured to obtain, via the user interface, an
input with respect to the at least one force threshold and/or an input with respect
to a size of a stabilizer pad of at least one support leg, and to provide the at least
one force threshold and/or information on the size of the stabilizer pad to the control
apparatus based on the input.
[0125] An example (e.g., example 25) relates to a method for a lifting device, comprising
receiving (310) force measurements from force sensors associated with support legs
being used to stabilize the lifting device, comparing (320) the force measurements
to at least one force threshold, and providing (330) a control signal to control at
least one indicator based on the comparison.
[0126] An example (e.g., example 26) relates to a method for a remote-control device for
controlling a lifting device, comprising receiving (410), from a control apparatus
for controlling the lifting device, a control signal to control an indicator of the
remote-control device, wherein the control signal is based on a comparison between
force measurements of force sensors associated with support legs being used to stabilize
the lifting device and at least one force threshold, and controlling (420) the indicator
of the remote-control device based on the control signal.
[0127] Another example (e.g., example 27) relates to a computer program having a program
code for performing the method of one of the examples 25 or 26, when the computer
program is executed on a computer, a processor, or a programmable hardware component.
[0128] The aspects and features described in relation to a particular one of the previous
examples may also be combined with one or more of the further examples to replace
an identical or similar feature of that further example or to additionally introduce
the features into the further example.
[0129] Examples may further be or relate to a (computer) program including a program code
to execute one or more of the above methods when the program is executed on a computer,
processor or other programmable hardware component. Thus, steps, operations or processes
of different ones of the methods described above may also be executed by programmed
computers, processors or other programmable hardware components. Examples may also
cover program storage devices, such as digital data storage media, which are machine-,
processor- or computer-readable and encode and/or contain machine-executable, processor-executable
or computer-executable programs and instructions. Program storage devices may include
or be digital storage devices, magnetic storage media such as magnetic disks and magnetic
tapes, hard disk drives, or optically readable digital data storage media, for example.
Other examples may also include computers, processors, control units, (field) programmable
logic arrays ((F)PLAs), (field) programmable gate arrays ((F)PGAs), graphics processor
units (GPU), application-specific integrated circuits (ASICs), integrated circuits
(ICs) or system-on-a-chip (SoCs) systems programmed to execute the steps of the methods
described above.
[0130] It is further understood that the disclosure of several steps, processes, operations
or functions disclosed in the description or claims shall not be construed to imply
that these operations are necessarily dependent on the order described, unless explicitly
stated in the individual case or necessary for technical reasons. Therefore, the previous
description does not limit the execution of several steps or functions to a certain
order. Furthermore, in further examples, a single step, function, process or operation
may include and/or be broken up into several sub-steps, -functions, -processes or
-operations.
[0131] If some aspects have been described in relation to a device or system, these aspects
should also be understood as a description of the corresponding method. For example,
a block, device or functional aspect of the device or system may correspond to a feature,
such as a method step, of the corresponding method. Accordingly, aspects described
in relation to a method shall also be understood as a description of a corresponding
block, a corresponding element, a property or a functional feature of a corresponding
device or a corresponding system.
[0132] The following claims are hereby incorporated in the detailed description, wherein
each claim may stand on its own as a separate example. It should also be noted that
although in the claims a dependent claim refers to a particular combination with one
or more other claims, other examples may also include a combination of the dependent
claim with the subject matter of any other dependent or independent claim. Such combinations
are hereby explicitly proposed, unless it is stated in the individual case that a
particular combination is not intended. Furthermore, features of a claim should also
be included for any other independent claim, even if that claim is not directly defined
as dependent on that other independent claim.