FIELD
[0001] The present invention relates generally to robotic systems and, more specifically, to docking systems for mobile robots.
BACKGROUND
[0002] Automated robots and robotic devices are used to perform tasks traditionally considered mundane, time-consuming, or dangerous. As the programming technology increases, so too does the demand for robots that require a minimum of human interaction for tasks such as robot refueling, testing, and servicing. A goal is a robot that could be configured a single time, which would then operate autonomously, without need for human assistance or intervention.
SUMMARY OF THE INVENTION
[0003] According to embodiments of the invention, a mobile robot system includes a docking station and a mobile robot. The docking station includes a platform having a front and a rear, first and second raised charging contacts on the platform, and first and second ramp features on the platform. The mobile robot includes a housing, a motorized drive system connected to the housing and including first and second drive wheels, first and second charging contacts on a bottom of the housing, and a cleaning module including at least one rotatable cleaning head that extends below the bottom of the housing. The mobile robot is movable from an approach position with the mobile robot spaced apart from the front of the platform to a docked position with the mobile robot on the platform and the docking station charging contacts engaged with the mobile robot charging contacts. As the mobile robot moves from the approach position to the docked position, the mobile robot engages the first and second ramp features and the cleaning module is lifted over the docking station charging contacts.
[0004] According to embodiments of the invention, a method for docking a mobile cleaning robot with a docking station includes: advancing the mobile cleaning robot onto a platform of the docking station; while advancing the mobile cleaning robot onto the platform of the docking station, lifting a cleaning mechanism that extends below a bottom of a housing of the robot over at least one charging contact on the platform by advancing the robot over at least one elongated ramp feature on the platform; and docking the robot in a docked position on the platform with at least one charging contact on the bottom of the housing of the robot engaging the at least one charging contact on the platform and with the cleaning mechanism positioned between the at least one charging contact on the platform and a rear of the platform.
[0005] Further features, advantages and details of the present invention will be appreciated by those of ordinary skill in the art from a reading of the figures and the detailed description of the embodiments that follow, such description being merely illustrative of the present invention.
BRIEF DESCRIPTIONS OF THE DRAWINGS
[0006]
FIG. 1 is a perspective view of a mobile robot system according to embodiments of the invention.
FIG. 2 is a cross-sectional view of a robot forming a part of the system of FIG. 1.
FIG. 3 is a bottom perspective view of the robot of FIG. 2.
FIG. 4 is a top view of the robot of FIG. 2.
FIG. 5 is a perspective view of a dock forming a part of the system of FIG. 1.
FIG. 6 is a side view of the dock of FIG. 5.
FIG. 7 is a schematic diagram illustrating operations of a communications/guidance system forming a part of the system of FIG. 1.
FIGS. 8-13 are sequential side views of a robot of the system of FIG. 1 advancing from an approach position to docked position on a dock of the system of FIG. 1.
FIG. 14 is a fragmentary perspective view of an evacuation dock according to embodiments of the invention.
FIG. 15 is a side view of the evacuation dock of FIG. 14.
FIGS. 16-21 are sequential side views of a robot of the system of FIG. 1 advancing from an approach position to docked position on the evacuation dock of FIG. 14.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0007] The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which illustrative embodiments of the invention are shown. In the drawings, the relative sizes of regions or features may be exaggerated for clarity. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
[0008] It will be understood that when an element is referred to as being "coupled" or "connected" to another element, it can be directly coupled or connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly coupled" or "directly connected" to another element, there are no intervening elements present. Like numbers refer to like elements throughout.
[0009] In addition, spatially relative terms, such as "under", "below", "lower", "over", "upper" and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "under" or "beneath" other elements or features would then be oriented "over" the other elements or features. Thus, the exemplary term "under" can encompass both an orientation of over and under. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
[0010] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein the expression "and/or" includes any and all combinations of one or more of the associated listed items.
[0011] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[0012] The term "monolithic" means an object that is a single, unitary piece formed or composed of a material without joints or seams.
[0013] With reference to
FIGS. 1-14, a mobile robot system
10 according to some embodiments is shown therein. The system
10 includes a vacuum cleaning robot
100 and a base station or dock
200 (also referred to herein as a docking station). The system
10 may include an evacuation dock
300 (FIG. 14) in addition to or in place of the dock
200. The robot
100 is adapted to mate with the dock
200 and the evacuation dock
300.
[0014] The system
10 also includes a charging or energy management system
205 and an auto-docking control system
201 each including cooperatively operating components of the robot
100 and the dock
200. In some embodiments, the energy management system
205 includes a charging circuit (including charging contacts
222A, 222B in the dock
200 and charging contacts
164A, 164B in the robot
100) to enable charging of the robot
100 by the dock
200.
[0015] In the following description of the autonomous robot
100, use of the terminology "forward/fore" refers generally to the primary direction of motion of the robot
100, and the terminology fore-aft axis (see reference characters
"FA" in
FIG. 4) defines the forward direction of motion
F (FIG. 4), which is coincident with the fore-aft diameter of the robot
100.
[0016] The robot
100 further defines a lateral or left-right axis
LA and a vertical axis
VA that are perpendicular to one another and to the axis
FA. The axes
FA and
LA define a plane that is substantially parallel to the plane defined by the points of contact of the wheels
132 and caster
134 (described below) or the support surface (
e.g., floor) on which the robot
100 rests.
[0017] The description also uses a frame of reference based on the dock
200 including X-, Y- and Z-axes, which are depicted in
FIG. 5. The X-, Y- and Z-axes are perpendicular to one another and intersect at the center of the dock
200. Movements, distances and dimensions along the Y-axis may be referred to as lateral, leftward or rightward. Movements, distances and dimensions along the X-axis may be referred to herein as depthwise, fore-aft, forward or rearward. Movements, distance and dimensions along the Z-axis may be referred to herein as vertical. The X- and Y-axes define a plane that is parallel to the support surface on which the dock
200 rests (
e.g., a floor).
[0018] In the embodiment depicted, the robot
100 includes a robot controller
102, a body, housing infrastructure or housing (hereinafter, "housing")
111, an electrical energy storage battery
126, a motive system
130, a cleaning system
140, a detector system
150, and an energy management or charging subsystem
160. The detector system
150 forms a part of the auto-docking control system
201.
[0019] The housing
111 has an undercarriage
115 (FIG. 3) and defines an internal main chamber
118 (FIG. 2). The undercarriage
115 forms the underside or bottom side of the housing
111 and the robot
100. The housing
111 includes a chassis
110, a top cover
112, a bottom or undercarriage cover
114, and a displaceable bumper
116. The robot
100 may move in a forward direction
F and a reverse drive direction
R; consequently, the chassis
110 has corresponding forward and back ends,
110A and
110B, respectively.
[0020] The chassis
110 may be molded from a material such as plastic as a unitary or monolithic element that includes a plurality of preformed wells, recesses, and structural members for,
inter alia, mounting or integrating elements of the various subsystems that operate the robot
100. The covers
112, 114 may be molded from a material such as a polymeric material (plastic) as respective unitary or monolithic elements that are complementary in configuration with the chassis
110 and provide protection of and access to elements and components mounted to the chassis
110. The chassis
110 and the covers
112, 114 are detachably integrated in combination by any suitable means (
e.g., screws). In some embodiments and as shown, the housing
111 has a front end defining a square profile. In some embodiments, the chassis
110 and covers
112, 114 form a structural envelope of minimal height having a generally D-shaped configuration that is generally symmetrical along the fore-aft axis
FA.
[0021] An evacuation port
120 is defined in the undercarriage cover
114 and the bottom wall
110C of the chassis
110. The evacuation port
120 may be provided with a closure device or flap.
[0022] The displaceable bumper
116 has a shape generally conforming to that of the front end of the chassis
110 and is mounted in movable combination at the forward portion of the chassis
110 to extend outwardly therefrom (the "normal operating position"). The mounting configuration of the displaceable bumper
116 is such that it is displaced towards the chassis
110 (from the normal operating position) whenever the bumper
116 encounters a stationary object or obstacle of predetermined mass (the "displaced position"), and returns to the normal operating position when contact with the stationary object or obstacle is terminated (due to operation of a control sequence which, in response to any such displacement of the bumper
116, implements a "bounce" mode that causes the robot
100 to evade the stationary object or obstacle and continue its task routine).
[0023] Installed along either lateral side of the chassis
110 are independent drive wheels
132 that mobilize the robot
100 and provide two points of contact with the floor surface. The drive wheels
132 may be spring loaded. The rear end
110B of the chassis
110 includes a non-driven, multi-directional caster wheel
134 that provides additional support for the robot
100 as a third point of contact with the floor surface. One or more electric drive motors
136 are disposed in the housing
111 and operative to independently drive the wheels
132. The motive components may include any combination of motors, wheels, drive shafts, or tracks as desired, based on cost or intended application of the robot
100.
[0024] In some embodiments, the cleaning system
140 includes a suction slot or opening
142A defined in the undercarriage
115. One or more motor driven rotating cleaning mechanisms or extractors (
e.g., brushes, cleaning heads, or rollers)
144 flank the opening
142A. A cleaning module
143 may include the extractors
144. An electric vacuum fan
146 pulls air up through a gap between the extractors
144 to provide a suction force that assists the extractors in extracting debris from the floor surface. Air and debris that pass through the gap are routed through a plenum
142B that leads to an opening of a cleaning or debris bin
145 disposed or encased in the chamber
118. The opening leads to a debris collection cavity
145A of the debris bin
145. A filter
147 located above the cavity screens the debris from an air passage leading to the air intake of the vacuum fan
146. Filtered air exhausted from the vacuum fan
146 is directed through an exhaust port
122.
[0025] A side brush
148 is mounted along the sidewall of the chassis
110 proximate the forward end
110A and ahead of the extractors
144 in the forward drive direction
F. The side brush
148 rotatable about an axis perpendicular to the floor surface. The side brush
148 allows the robot
100 to produce a wider coverage area for cleaning along the floor surface. In particular, the side brush
148 may flick debris from outside the area footprint of the robot
100 into the path of the centrally located cleaning head assembly.
[0027] The robot controller circuit
102 (depicted schematically) is carried by the chassis
110. The robot controller
102 is configured (
e.g., appropriately designed and programmed) to govern over various other components of the robot
100 (
e.g., the extractors
144, the side brush
148, and/or the drive wheels
132). As one example, the robot controller
102 may provide commands to operate the drive wheels
132 in unison to maneuver the robot
100 forward or backward. As another example, the robot controller
102 may issue a command to operate one drive wheel
132 in a forward direction and the other drive wheel
132 in a rearward direction to execute a clock-wise turn. Similarly, the robot controller
102 may provide commands to initiate or cease operation of the rotating extractors
144 or the side brush
148. In some embodiments, the robot controller
102 is designed to implement a suitable behavior-based-robotics scheme to issue commands that cause the robot
100 to navigate and clean a floor surface in an autonomous fashion. The robot controller
102, as well as other components of the robot
100, may be powered by the battery
126 disposed on the chassis
110.
[0028] The detector system
150 (FIG. 4) includes a top or communications/guidance signal receiver or detector
152, proximity or wall following sensors
153, cliff sensors
154, a forward directional receiver or detector
156, an optical mouse sensor
157, and a camera
159. In some embodiments, each of these sensors or detectors is communicatively coupled to the robot controller
102. The robot controller
102 implements the behavior-based-robotics scheme based on feedback received from the plurality of sensors distributed about the robot
100 and communicatively coupled to the robot controller
102.
[0029] The proximity sensors
153 (depicted schematically) are installed along the periphery of the robot
100 proximate the front corners of the robot
100. The proximity sensors
153 are responsive to the presence of potential obstacles that may appear in front of or beside the robot
100 as the robot
100 moves in the forward drive direction
F.
[0030] The cliff sensors
154 are installed along the forward end
110A of the chassis
110. The cliff sensors
154 are designed to detect a potential cliff, or flooring drop, forward of the robot
100 as the robot
100 moves in the forward drive direction
F. More specifically, the cliff sensors
154 are responsive to sudden changes in floor characteristics indicative of an edge or cliff of the floor surface (
e.g., an edge of a stair).
[0031] The communications/guidance signal detector
152 is mounted on the top front of the housing
111 of the robot
100. The detector
152 is operable to receive signals projected from an emitter (
e.g., the avoidance signal emitter
232 and/or the homing and alignment emitters
234R, 234L of the dock
200) and (optionally) an emitter of a navigation or virtual wall beacon. In some embodiments, the robot controller
102 may cause the robot
100 to navigate to and dock with the dock
200 in response to the communications detector
152 receiving a home signal emitted by the dock
200.
[0032] In some embodiments and as shown, the detector
152 is mounted at the highest point on the robot
100 and toward the front of the robot
100 as defined by the primary traveling direction, as indicated by an arrow on axis
FA. In alternative embodiments, multiple detectors can be used in place of the top signal detector
152. Such an embodiment might include using multiple side-mounted sensors or detectors. Each of the sensors can be oriented in a manner so that a collective field of view of all the sensors corresponds to that of the single, top mounted sensor. Because a single, omni-directional detector is mounted at the highest point of the robot for optimal performance, it is possible to lower the profile of the robot by incorporating multiple, side mounted detectors.
[0033] The forward directional detector
156 is mounted on the front end of the robot
100 and may be mounted on or behind the bumper
116. The forward directional detector
156 receives signals projected from the emitters
234R, 234L on the dock
200. In other embodiments, a pair of detectors receive signals from the emitters
234R, 234L or more than two detectors may be used.
[0034] In some embodiments, the detectors
154, 156 are infrared ("IR") sensor or detector modules, that include a photodiode and related amplification and detection circuitry, in conjunction with an omni-directional lens, where omni-directional refers to a substantially single plane. Any detector, regardless of modulation or peak detection wavelength, can be used as long as the emitters
232, 234R, 234L on the base dock
200 are adapted to match the detectors
152, 156 on the robot
100. In another embodiment, IR phototransistors may be used with or without electronic amplification elements and may be connected directly to the analog inputs of a microprocessor. Signal processing may then be used to measure the intensity of IR light at the robot
100, which provides an estimate of the distance between the robot
100 and the source of IR light.
[0035] The camera
159 is a vision based sensor, such as a camera, having a field of view optical axis oriented in the forward drive direction of the robot
100. In the illustrated embodiment, the camera
159 is located at the rear end
110A of the robot with its line of sight angled forwardly and upwardly over the detector
152. In some embodiments, the camera
159 is a video camera. In some embodiments, the camera
159 is used for detecting features and landmarks in the operating environment and building a map using Video Simultaneous Localization and Mapping (VSLAM) technology.
[0036] The optical mouse sensor
157 is located on the undercarriage
115 of the robot
100. The circle shown in the top view of
FIG. 4 shows relative placement of the optical mouse sensor
157; however, the sensor
157 would not be visible in this view. The mouse sensor
157 tracks flooring and assists with drift compensation to keep the robot
100 moving in straight ranks.
[0037] Various other types of sensors, though not shown in the illustrated examples, may also be incorporated in the robot
100 without departing from the scope of the present disclosure. For example, a tactile sensor responsive to a collision of the bumper
116 and/or a brush-motor sensor responsive to motor current of the brush motor may be incorporated in the robot
100.
[0038] The robot
100 may further include a bin detection system for sensing an amount of debris present in the cleaning bin
122 (
e.g., as described in
U.S. Patent Publication 2012/0291809, the entirety of which is hereby incorporated by reference).
[0039] The robot charging subsystem
160 includes a charging circuit
162 that includes the charging contacts
164A, 164B. The robot charging subsystem
160 forms a part of the energy management system
205.
[0040] The robot
100 may be modified to perform any suitable task(s). For example, the robot
100 may be used for floor waxing and polishing, floor scrubbing, ice resurfacing (as typically performed by equipment manufactured under the brand name Zamboni®), sweeping and vacuuming, unfinished floor sanding and stain/paint application, ice melting and snow removal, grass cutting, etc. In some embodiments, the robot is configured as a mobility base carrying a retractable mast on which a camera is mounted. Any number of components may be required for such tasks, and may each be incorporated into the robot
100, as necessary. For simplicity, this application will describe vacuuming as the demonstrative predetermined task. The energy management and auto-docking functions disclosed herein have wide application across a variety of robotic systems.
[0041] FIG. 5 is a schematic perspective view of a dock
200 in accordance with one embodiment of the invention. The dock
200 includes a housing
202 including both a substantially horizontal base plate or platform
204 and a substantially vertical tower or backstop
206. The platform
204 includes a front
208 and a rear
210. The backstop
206 is at the rear
210 of the platform
204. A docking bay
DB is defined over the platform
204 and in front of the backstop
206. The dock
200 may be any of a variety of shapes or sizes, providing sufficient space for the desired components and systems, described below.
[0042] The platform
204 includes a left side portion
212 and a right side portion
214. A first or left track
216A is on the left side portion
212 of the platform
204 and a second or right track
216B is on the right side portion
212 of the platform
204. The platform
204 includes a central portion
218 between the left and right side portions
212, 214.
[0043] The platform
204 is generally parallel to the ground surface on which the dock
200 rests or may be slightly ramped to provide space for wiring.
[0044] The dock
200 includes a dock charging subsystem
220, a communications/guidance system
230, a dock controller
224, and a power input connector
226 (connected to a power supply, not shown). The dock charging subsystem
220 forms a part of the energy management system
205. The dock charging subsystem
220 includes a charging circuit
221, which includes first and second charging contacts
222A, 222B on the central portion
218 of the platform
204. As described in more detail below, the charging contacts
222A, 222B are configured to engage the charging contacts
164A, 164B of the robot
100 (FIG. 3) when the robot
100 is in a docked position on the dock
200. The charging contacts
222A, 222B may be spring loaded.
[0045] The dock controller circuit
224 (depicted schematically) is carried by the housing
202. The dock controller
224 is configured (
e.g., appropriately designed and programmed) to govern over various other components of the dock
200.
[0046] The communications/guidance system
230 (FIG. 5) may include a top signal emitter
232, a first or right front homing/alignment emitter
234R, and a second or left front homing/alignment emitter
234L.
[0047] The top signal emitter
232 may be mounted on the top of the backstop
206. The emitter
232 generates a first signal, such as an avoidance signal
BA (FIG. 5), in a diffuse region near the dock
200 to prevent the robot from coming into inadvertent direct contact with the dock
200 while performing a task, such as vacuuming. The top signal emitter
232 may utilize a parabolic reflector to transmit the avoidance signal. In such an embodiment, the avoidance signal is emitted by a single LED directed at a lens whose geometry is determined by rotating a parabola about its focus. This parabolic reflector thus projects the avoidance signal
BA without the necessity of multiple emitters. A similar configuration can be employed in the detector
156 on the robot, with a single receiver used in place of the single LED.
[0048] The homing/alignment emitters
234R, 234L are located on a front wall
206A of the backstop
206. The homing/alignment emitters
234R and
234L emit or project respective homing signals
BR and
BQ (FIG. 7) as discussed below. In some embodiments, the emitters
234R, 234L are LEDs. The emitters
234R, 234L serve as navigational buoys or fiducials. In some embodiments and as shown, the emitters
234R, 234L are laterally offset from the centerline
X-X of the dock
200 and the directional detector
156 is offset from the centerline
FA of the robot
100 so that the detector
156 is substantially centered between the emitters
234R, 234L when the robot
100 is in the docked position.
[0049] The robot
100 uses a variety of behavioral modes to effectively vacuum a working area. Behavioral modes are layers of control systems that can be operated in parallel. The robot controller
102 (
e.g., microprocessor) is operative to execute a prioritized arbitration scheme to identify and implement one or more dominant behavioral modes for any given scenario, based upon inputs from the sensor system. The robot controller
102 is also operative to coordinate avoidance, homing, and docking maneuvers with the dock
200.
[0050] Generally, the behavioral modes for the described robot
100 can be characterized as: (1) coverage behavioral modes; (2) escape behavioral modes, and (3) safety behavioral modes. Coverage behavioral modes are primarily designed to allow the robot
100 to perform its operations in an efficient and effective manner, while the escape and safety behavioral modes are priority behavioral modes implemented when a signal from the sensor system indicates that normal operation of the robot
100 is impaired (
e.g., obstacle encountered), or is likely to be impaired (
e.g., drop-off detected).
[0051] Representative and illustrative coverage behavioral modes (for vacuuming) for the robot
100 include: (1) a Spot Coverage pattern; (2) an Obstacle-Following (or Edge-Cleaning) Coverage pattern, and (3) a Room Coverage pattern. The Spot Coverage pattern causes the robot
100 to clean a limited area within the defined working area,
e.g., a high-traffic area. In a certain embodiments the Spot Coverage pattern is implemented by means of a spiral algorithm (but other types of self-bounded area algorithms, such as polygonal, can be used). The spiral algorithm, which causes outward or inward spiraling movement of the robot
100, is implemented by control signals from the microprocessor to the motive system to change the turn radius/radii thereof as a function of time or distance traveled (thereby increasing/decreasing the spiral movement pattern of the robot
100).
[0052] The foregoing description of typical behavioral modes for the robot
100 are intended to be representative of the types of operating modes that can be implemented by the robot
100. One skilled in the art will appreciate that the behavioral modes described above can be implemented in other combinations and other modes can be defined to achieve a desired result in a particular application.
[0053] A navigational control system may be used advantageously in combination with the robot
100 to enhance the cleaning efficiency thereof, by adding a deterministic component (in the form of a control signal that controls the movement of the robot
100) to the motion algorithms, including random motion, autonomously implemented by the robot
100. The navigational control system operates under the direction of a navigation control algorithm. The navigation control algorithm includes a definition of a predetermined triggering event.
[0054] Broadly described, the navigational control system, under the direction of the navigation control algorithm, monitors the movement activity of the robot
100. In one embodiment, the monitored movement activity is defined in terms of the "position history" of the robot
100, as described in further detail below. In another embodiment, the monitored movement activity is defined in terms of the "instantaneous position" of the robot
100.
[0055] The predetermined triggering event is a specific occurrence or condition in the movement activity of the robot
100. Upon the realization of the predetermined triggering event, the navigational control system operates to generate and communicate a control signal to the robot
100. In response to the control signal, the robot
100 operates to implement or execute a conduct prescribed by the control signal,
i.e., the prescribed conduct. This prescribed conduct represents a deterministic component of the movement activity of the robot
100.
[0056] The camera
159 can be used to navigate the robot and acquire images for other operational use. In some embodiments, the camera
159 is a VSLAM camera and is used to detect features and landmarks in the operating environment and build a map.
[0057] While the robot
100 is vacuuming, it will periodically approach the stationary dock
200. Contact with the dock
200 could damage or move the dock
100 into an area that would make docking impossible. Therefore, avoidance functionality is desirable. To avoid inadvertent contact, the dock
200 may generate an avoidance signal
BA, as depicted in
FIG. 5. The avoidance signal
BA is shown being transmitted from the emitter
232 on the top of the backstop
206. The radial range of the avoidance signal
BA from the dock
200 may vary, depending on predefined factory settings, user settings, or other considerations. At a minimum, the avoidance signal
BA need only project a distance sufficient to protect the dock
200 from unintentional contact with the robot
100. The avoidance signal
BA range can extend from beyond the periphery of the dock
200, to up to and beyond several feet from the dock
200, depending on the application.
[0058] The avoidance signal
BA may be an omni-directional (
i.e., single plane) infrared beam, although other signals are contemplated, such as a plurality of single stationary beams or signals. If stationary beams are used, however, a sufficient number could provide adequate coverage around the dock
200 to increase the chances of the robot
100 encountering them. When the detector
152 of the robot
100 receives the avoidance signal
BA from the emitter
232, the robot
100 can alter its course, as required, to avoid the dock
200. Alternatively, if the robot
100 is actively or passively seeking the dock
200 (for recharging or other docking purposes), it can alter its course toward the dock
200, such as by circling the dock
200, in such a way to increase the chances of encountering the homing signals as described below.
[0059] Generally, the avoidance signal
BA is modulated and coded, as are the homing signals
BR, BQ. The bit encoding method as well as binary codes are selected such that the robot
100 can detect the presence of each signal, even if the robot
100 receives multiple codes simultaneously.
[0060] Whenever measurable level of IR radiation from the avoidance signal
BA strikes the detector
152, the robot's IR avoidance behavior is triggered. In one embodiment, this behavior causes the robot
100 to spin in place to the left until the IR signal falls below detectable levels. The robot
100 then resumes its previous motion. In one embodiment, the detector
152 acts as a gradient detector. When the robot
100 encounters a region of higher IR intensity, the robot
100 spins in place. Because the detector
152 is mounted at the front of the robot
100 and because the robot
100 does not move backward, the detector
152 always "sees" the increasing IR intensity before other parts of the robot
100. Thus, spinning in place causes the detector
152 to move to a region of decreased intensity. When the robot
100 next moves forward, it necessarily moves to a region of decreased IR intensity-away from the avoidance signal
BA.
[0061] In other embodiments, the dock
200 includes multiple coded emitters at different power levels or emitters that vary their power level using a system of time multiplexing. These create concentric coded signal rings which enable the robot
100 to navigate towards the dock
200 from far away in the room. Thus, the robot
100 would be aware of the presence of the dock
200 at all times, facilitating locating the dock
200, docking, determining how much of the room has been cleaned, etc. Alternatively, the robot
100 uses its motion through the IR field to measure a gradient of IR energy. When the sign of the gradient is negative (
i.e., the detected energy is decreasing with motion), the robot
100 goes straight (away from the IR source). When the sign of the gradient is positive (energy increasing), the robot
100 turns. The net effect is to implement a "gradient descent algorithm," with the robot
100 escaping from the source of the avoidance signal
BA. This gradient method may also be used to seek the source of emitted signals. The concentric rings at varying power levels facilitate this possibility even without a means for determination of the raw signal strength.
[0062] In some embodiments, in order to dock, the system
10 executes a docking procedure. The docking procedure terminates with the robot
100 in a final, prescribed docked position
DP (FIG. 1) within the docking bay
DB. The docked position
DP may include permitted tolerances or deviation from a precise target docked position.
[0063] The robot
100 may assume its seeking mode and seek the dock
200 when it detects the need to recharge its battery, or when it has completed vacuuming the room. This mode can also be triggered by actuating a hardware interface such as a button on the robot
100 and/or by using a portable electronic device (e.g., a smartphone app).
[0064] In the docking procedure, the robot
100 uses the homing signals
BR, BQ (FIG. 7) and its directional detector
156 to guide the robot
100. As with the avoidance signal
BA above, the projected range and orientation of the homing signals
BR, BQ may be varied, as desired. It should be noted however, that longer signals can increase the chance of the robot
100 finding the dock
200 efficiently. Longer signals can also be useful if the robot
100 is deployed in a particularly large room, where locating the dock
200 randomly could be inordinately time consuming. Homing signal
BR, BQ ranges that extend from approximately six inches beyond the front of the platform
210, to up to and beyond several feet beyond the platform
210 are contemplated, depending on application. The angular width of the homing signals
BR, BQ may vary depending on application, but angular widths in the range of 5° to up to and beyond 60° are contemplated. The angular width of each homing signal
BR, BQ may be the area covered by the beam or sweep of the homing signal
BR, BQ and, in some embodiments, is generally or substantially frusto-conical. A gradient behavior as described above can also be used to aid the robot in seeking out the dock
200.
[0065] The two homing signals
BR, BQ are distinguishable by the robot
100, for example as a first or lateral right homing signal
BR and a second or lateral left homing signal
BQ. IR beams are generally used to produce the signals and, as such, are not visible. The IR beams may be modulated. Any signal bit pattern may be used, provided the robot
100 recognizes which signal to orient to a particular side. Alternatively, the signals
BR, BQ may be distinguished by using different wavelengths or by using different carrier frequencies (
e.g., 380 kHz versus 38 kHz, etc.).
[0066] Thus, when the robot
100 wants or needs to dock, if the detector
156 receives the right signal
BR transmitting from the dock
200, it moves to keep the right signal
BR on the robot's right side; if it detects the left signal
BQ transmitting from the dock
200, it moves to keep the left signal
BQ on the robot's left side. Where the two signals overlap (the overlap zone
BO), the robot
100 knows that the dock
200 is nearby and may then dock. Such a system may be optimized to make the overlap zone
BO as thin as practicably possible, to ensure proper orientation and approach of the robot
100 and successful docking. Alternatively, the right signal
BR and left signal
BQ may be replaced by a single signal, which the robot
100 would follow until docked.
[0067] FIG. 7 depicts an exemplary path
RP the robot
100 may traverse during a docking procedure utilizing the homing signals. When the detector
156 is in the left signal
156 field, the robot
100 will move towards the right, in direction
MR in an effort to keep that left signal
BQ to the left of the robot
100. When the detector
156 is in the right signal
BR field, thus the robot
100 will move towards the left, in direction
ML in an effort to keep that right signal
BR to the right of the detector
156. Last, when the detector
156 encounters the overlap zone
BO, the robot
100 will move in direction
MD directly towards the dock
100.
[0068] While approaching the dock
200, the robot
100 may slow its speed of approach and/or discontinue vacuuming, or perform other functions to ensure trouble-free docking. These operations may occur when the robot
100 detects the avoidance signal
BA, thus recognizing that it is close to the dock
200, or at some other predetermined time,
e.g., upon a change in the signal from the emitters
234R, 234L.
[0069] In other embodiments, the camera
159 (
e.g., a VSLAM camera) is used to detect the dock
200 in order to guide the robot
100 in the docking procedure. The camera
159 may also be used to build and use a map using VSLAM technology as discussed above. For example, in some embodiments, the camera
159 is aimed upward (
e.g., to view locations 3-8 feet above the floor) to view objects or features (
e.g., picture frames and doorway frames and edges) for mapping and localizing the robot
100 relative to these landmarks (
i.e., groupings of features).
[0070] In addition to operating as navigational beacons, homing signals
BR, BQ and/or the avoidance signal
BA may also be used to transmit information, including programming data, fail safe and diagnostic information, docking control data and information, maintenance and control sequences, etc. In such an embodiment, the signals can provide the control information, dictating the robot's reactions, as opposed to the robot
100 taking certain actions upon contacting certain signals from the dock
200. In that case, the robot
100 functions as more of a slave to the dock
200, operating as directed by the signals sent. In other embodiments, separate IR LEDs and emitters can be used for transmitting data, information, etc. There may be two-way communication between the robot
100 and the dock
200.
[0071] In the docking procedure, the robot
100 may use the navigational aids described herein to adjust the lateral alignment of the robot
100 with respect to the dock
200, the angular orientation of the robot
100 with respect to the dock
200, and/or the depthwise position of the robot
100 into the dock
200 (
i.e., proximity to the backstop
206).
[0072] Generally, the control sequence for vacuuming can include three subsequences based on the measured energy level of the robot
100. Those are referenced generally as a high energy level, a medium energy level, and a low energy level. In the high energy level subsequence, the robot
100 performs its predetermined task, in this case, vacuuming (utilizing various behavioral modes as described above), while avoiding the dock
200. When avoiding the dock
200, the robot
100 performs its avoidance behavior and continues to operate normally. This process continues while the robot
100 continually monitors its energy level. Various methods are available to monitor the energy level of the power source, such as coulometry (
i.e., the measuring of current constantly entering and leaving the power source), or simply measuring voltage remaining in the power source. Other embodiments of the robot
100 may simply employ a timer and a look-up table stored in memory to determine how long the robot
100 can operate before it enters a different energy level subsequence. Still other embodiments may simply operate the robot
100 for a predetermined time period before recharging, without determining which energy level subsequence it is operating in. If the robot
100 operates on a liquid or gaseous fuel, this level may also be measured with devices currently known in the art.
[0073] Once the energy remaining drops below a predetermined high level, the robot
100 enters its medium energy level sequence. The robot
100 continues to vacuum and monitor its energy level. In the medium energy level, however, the robot
100 "passively seeks" the dock
200. While passively seeking the dock
200, the robot
100 does not alter its travel characteristics; rather, it continues about its normal behavioral mode until it detects the avoidance signal
BA or a homing signal
BR, BQ, each of which may be followed until the robot
100 ultimately docks with the dock
200. In other words, if the robot detects the avoidance signal
BA while passively seeking, rather than avoiding the dock
200 as it normally would, it alters its travel characteristics until it detects the homing signal
BR or
BQ, thus allowing it to dock.
[0074] Alternatively, the robot
100 continues operating in this medium energy level subsequence until it registers an energy level below a predetermined low level. At this point, the robot
100 enters the low level subsequence, characterized by a change in operation and travel characteristics. To conserve energy, the robot
100 may discontinue powering all incidental systems, and operations, such as vacuuming, allowing it to conserve as much energy as possible for "actively searching" for the dock
200. While actively searching, the robot
100 may alter its travel characteristics to increase its chances of finding the dock
200. It may discontinue behavioral modes such as those employing a spiral movement, which do not necessarily create a higher chance of locating the dock
200, in favor of more deliberate modes, such as wall-following. This deliberate seeking will continue until the robot
100 detects the presence of the dock
200, either by detecting the avoidance signal
BA or the homing signals
BR, BQ. Clearly, additional subsequences may be incorporated which sound alarms when the power remaining reaches a critical level, or which reconstruct the route the robot
100 has taken since last contacting the dock
200 to aid in relocating the dock
200.
[0075] The robot
100 may also dock because it has determined that it has completed its assigned task (
e.g., vacuuming a room) or its bin needs to be emptied. The robot
100 may make this determination based on a variety of factors, including considerations regarding room size, total run time, total distance traveled, dirt sensing, etc. Alternatively, the robot may employ room-mapping programs, using the dock
200 and/or walls and large objects as points of reference. Upon determining that it has completed its task, the robot
100 will alter its travel characteristics in order to find the dock
200 quickly. The dock
200 may include a charging system only (
i.e., a charging dock) or may include both a charging system and an evacuation system or station operative to empty debris from the bin of the robot
100.
[0076] Once the robot
100 is in the docked position, it can recharge itself autonomously. Circuitry within the dock
200 detects the presence of the robot
100 and then switches on the charging voltage to the charging contacts
222A, 222B.
[0077] While docked with the dock
200, the robot
100 can also perform other maintenance or diagnostic checks. In certain embodiments, the robot
100 can completely recharge its power source or only partially charge it, based on various factors. Other behaviors while in the docking position such as diagnostic functions, internal mechanism cleaning, communication with network, or data manipulation functions may also be performed.
[0078] The platform
206 includes first and second ramp features such as first and second ramps
240A, 240B. The robot
100 is movable between an approach position with the robot
100 spaced apart from the platform
206 (FIG. 8) and a docked position
(FIG. 13) with the robot
100 on the platform
206 and the docking station charging contacts
222A, 222B engaged with the robot charging contacts
164A, 164B. As described in more detail below, the first and second ramp features are positioned and configured such that, as the robot
100 moves from the approach position to the docked position, the robot
100 engages the ramp features and the cleaning module
143 of the robot is lifted over the docking station charging contacts
222A, 222B. The ramp features therefore help prevent the robot from damaging the docking station charging contacts as the robot drives onto the docking station platform by raising the cleaning module up and over the docking station charging contacts.
[0079] Referring to
FIG. 5, the first ramp
240A is on the first track
216A and the second ramp
240B is on the second track
216B. Each of the first and second ramps
240A, 240B may include a raised flat surface
242, a first inclined or sloped surface
244, and a second inclined or sloped surface
246. The first sloped surface
244 may extend downwardly from the raised flat surface
242 toward the front
208 of the platform
204 and the second sloped surface
246 may extend downwardly from the raised flat surface
242 toward the rear
210 of the platform
204.
[0080] The dock
200 may rest on a cleaning surface S. Each of the ramps
240A, 240B (or each of the raised surfaces
242) may have a height
H1 of between 7 mm and 10 mm relative to the cleaning surface
S and, in some embodiments, have a height
H1 of 8.5 mm relative to the cleaning surface
S. Each of the charging contacts
222A, 222B may extend a distance
H2 of between 14 mm and 18 mm above the cleaning surface
S and, in some embodiments, extend a distance
H2 of 16 mm above the cleaning surface
S.
[0081] The left side portion
212 of the platform
204 and/or the first track
216A may include a second flat surface
248A that extends from the second sloped surface
246 of the first ramp
240A toward the rear
210 of the platform
204. Similarly, the right side portion
214 of the platform
204 and/or the second track
216B may include a second flat surface
248B that extends from the second sloped surface
246 of the second ramp
240B toward the rear
210 of the platform
204.
[0082] The central portion
218 of the platform
204 may include a raised surface
252 and a first inclined or sloped surface
254 with the first sloped surface
254 extending downwardly from the raised surface
252 toward the front
208 of the platform
204. The raised surface
252 may be flat or substantially flat. The first and second charging contacts
222A, 222B are on the raised surface
252. Each of the charging contacts
222A, 222B may have a height
H3 of between 2 mm and 5 mm relative to the raised surface
252 and, in some embodiments, have a height
H3 of 3.7 mm relative to the raised surface
252. The raised surface
252 may be positioned vertically above the second sloped surfaces
246 of each of the first and second ramps
240A, 240B and/or the second flat surfaces
248A, 248B of each of the left and right side portions
212, 214 of the platform
204.
[0083] The central portion
218 of the platform
204 may include a second inclined or sloped surface
256 and a second flat surface
258. The second sloped surface
256 extends downwardly from the raised surface
252 to the second flat surface
258. The second flat surface
258 extends from the second sloped surface
256 toward the rear
210 of the platform
204.
[0084] FIGS. 8 to
13 illustrate the robot
100 sequentially moving from the approach position
(FIG. 8) to the docked position
(FIG. 13). With reference to
FIGS. 5, 6, and
9, as the robot
100 approaches the dock
200, the cleaning module
143 in the front portion of the robot
100 engages and rides up and along the first sloped surface
244 of the ramps
240A, 240B and then engages and rides along the raised surface
242 of the ramps
240A, 240B.
[0085] With reference to
FIGS. 5, 6, and
10, the wheels
132 of the robot
100 roll up the first sloped surfaces
244 of the ramps
240A, 240B and, in response, the cleaning module
143 rises upward (e.g., off the platform
204) as it approaches the dock charging contacts
222A, 222B. With reference to
FIGS. 5, 6, and
11, as the wheels
132 roll to the raised surfaces
242 of the ramps
240A, 240B, the cleaning module
143 rises further upward and is positioned vertically above the dock charging contacts
222A, 222B.
[0086] Referring to
FIG. 11, the robot
100 has a tilt angle
A1 relative to horizontal due to engagement with the ramps
240A, 240B. The tilt angle
A1 may be measured between the bottom
114 of the housing and the cleaning surface
S. The tilt angle
A1 may be between 6 degrees and 11 degrees and, in some embodiments, is about 8.5 degrees.
[0087] With reference to
FIGS. 5, 6, and
12, as the wheels
132 roll along the raised surfaces
242 of the ramps
240A, 240B, the cleaning module
143 remains raised above the dock charging contacts
222A, 222B and passes over the dock charging contacts
222A, 222B. The center of gravity
CG of the robot
100 may be behind the wheels
132 to facilitate the aforementioned actions.
[0088] With reference to
FIGS. 5, 6, and
13, as the wheels
132 reach and roll down the second sloped surfaces
246 of the ramps
240A, 240B, the cleaning module
143 has passed or substantially passed the dock charging contacts
222A, 222B and the cleaning module
143 and the robot
100 descend into the docked position. In the docked position, the robot charging contacts
164A, 164B (FIG. 3) engage the dock charging contacts
222A, 222B (FIG. 5).
[0089] In the docked position, the bottom
114 of the robot housing may be spaced apart from the raised flat surfaces
242 of the first and second ramps
240A, 240B. This may reduce wear on the bottom of the robot
100 as it enters and exits the dock
200.
[0090] In the docked position, the left wheel
132 of the robot
100 may be on the second sloped surface
246 of the ramp
240A and/or the second flat surface of the
248A of the left side
212 of the dock platform
204. In the docked position, the right wheel
132 may be on the second sloped surface
246 of the ramp
240B and/or the second flat surface of the
248B of the right side
214 of the dock platform
204. In the docked position, the cleaning module
143 of the robot
100 may be on the second flat surface
258 of the central portion
218 of the dock platform
214.
[0091] When the robot is deployed from the docked position, the ramps
240A, 240B cause the robot and its components to move in the reverse of the above-described motion. Thus, when the robot
100 is deployed, the cleaning module
143 is raised above the dock charging contacts
222A, 222B as the wheels
132 engage the ramps
240A, 240B.
[0092] The cleaning module
143 is located at the front of the robot
100 and at ground level, and therefore has the potential to scrape against the dock charging contacts
222A, 222B as the robot
100 approaches its charging or docked position, thereby posing a risk to the longevity of the charging contacts
222A, 222B. The present inventors addressed this problem by including the ramps
240A, 240B on the dock platform
204 such that the cleaning module
143 is lifted up and over the charging contacts
222A, 222B as described above.
[0093] FIGS. 14 and
15 show an evacuation dock
300 in accordance with one embodiment of the invention. The evacuation dock
300 includes a housing
302 including both a substantially horizontal base plate or platform
304 and a substantially vertical tower or backstop
306. A docking bay
DB is defined over the platform
304 and in front of the backstop
306. The evacuation dock
300 may be any of a variety of shapes or sizes, providing sufficient space for the desired components and systems, described below.
[0094] The platform
304 includes a front
308 and a rear
310 with the tower
306 at the rear
310 of the platform
304. The platform
304 includes a left side portion
312 and a right side portion
314. A first or left track
316A is on the left side portion
312 of the platform
304 and a second or right track
316B is on the right side portion
314 of the platform
304. The platform
304 includes a central portion
318 between the left and right side portions
312, 314.
[0095] An evacuation suction port
364 is defined in the central portion
318. The evacuation suction port
364 is offset from the lateral centerline of the platform
310 and the midpoint between the tracks
316A, 316B.
[0096] The platform
304 may be sloped at an upwards angle toward the backstop
320.
[0097] The evacuation dock
300 includes a charging subsystem
320, a communications/guidance system
330, a dock controller
324, and a power input connector
326 (connected to a power supply, not shown) corresponding to and operative in the same manner as the charging subsystem
220, the communications/guidance system
230, the dock controller
224, and the power input connector
226, respectively, except as discussed below. The evacuation dock
300 may include an avoidance emitter
332 and directional emitters
334R, 334L corresponding to the avoidance emitter
232 and the directional emitters
234R, 234L, respectively.
[0098] The charging subsystem
320 includes a charging circuit
321, which includes first and second charging contacts
322A, 322B on the central portion
318 of the platform
304. Like the charging contacts
222A, 222B, the charging contacts
322A, 322B are configured to engage the charging contacts
164A, 164B of the robot
100 (FIG. 3) when the robot
100 is in a docked position on the dock
300. The charging contacts
322A, 322B may be spring loaded.
[0099] The evacuation dock
300 further includes a debris evacuation system
360. The evacuation system
360 includes a debris bin
362 (which may be removable) in the tower
306, an evacuation port
364 located in the platform
304, a duct or ducts fluidly connecting the port
364 to the bin
362, and a suction fan
364 configured to draw debris from the evacuation port
364 and into the bin
362.
[0100] The wheel tracks
316A, 316B are designed to receive the robot's drive wheels
132 to guide the robot
100 onto the platform
304 in proper alignment with the evacuation suction port
364. The wheel tracks
316A, 316B includes depressed wheel wells
349A, 349B, respectively, that each hold a drive wheel
132 in place to positively align and locate the robot
100 relative to the platform
304, and to prevent the robot
100 from unintentionally sliding down the inclined platform
304 once docked.
[0101] The robot
100 can dock with the evacuation dock
300 by advancing onto the platform
304 and into the docking bay
DB of the evacuation dock
300 as described above with regard to the dock
200. Once the evacuation dock
300 receives the robot
100, the suction fan
364 generates a vacuum that draws debris from the cleaning bin
145 of the robot
100, through the platform
304, and into the debris bin
362.
[0102] When the robot
100 is docked in the prescribed docked position in the docking bay
DB, the robot charging contacts
164A, 164B are vertically aligned with and engage the dock charging contacts
322A, 322B. Additionally, the evacuation port
120 of the robot
100 will be aligned with and in contact with or in close proximity to the evacuation port
364 of the evacuation dock
300.
[0103] The robot
100 can avoid, discover, and approach the evacuation dock
300 in the same manner as described above with regard to the dock
200. The robot may rely on the wheel wells
349A, 349B to capture the wheels
132, thereby positively aligning and positioning the robots and ensuring that the robot is properly aligned in the final portion of the docking approach.
[0104] Referring to
FIGS. 14 and
15, the platform
306 includes first and second ramp features such as first and second ribs
340A, 340B. The robot
100 is movable between an approach position with the robot
100 spaced apart from the platform
306 (FIG. 16) and a docked position
(FIG. 21) with the robot
100 on the platform
306 and the docking station charging contacts
322A, 322B engaged with the robot charging contacts
164A, 164B. As described in more detail below, the first and second ramp features are positioned and configured such that, as the robot
100 moves from the approach position to the docked position, the robot
100 engages the ramp features and the cleaning module
143 of the robot is lifted over the docking station charging contacts
322A, 322B. The ramp features therefore help prevent the robot from damaging the docking station charging contacts as the robot drives onto the docking station platform by raising the cleaning module up and over the docking station charging contacts.
[0105] Referring to
FIG. 14, the first rib
340A is on the central portion
318 of the platform
304 or at an interface between the left side portion
312 of the platform
304 and the central portion
318 of the platform
304. The second rib
340A is on the central portion
318 of the platform
304 or at an interface between the right side portion
314 of the platform
304 and the central portion
318 of the platform
304. Each of the first and second ribs
340A, 340B may include a raised flat surface
342, a first inclined or sloped surface
344, and a second inclined or sloped surface
346. The first sloped surface
344 may extend downwardly from the raised flat surface
342 toward the front
308 of the platform
304 and the second sloped surface
346 may extend downwardly from the raised flat surface
342 toward the rear
310 of the platform
304.
[0106] Each of the ribs
340A, 340B may be on an inclined or sloped surface
354 of the platform
304. Referring to
FIG. 15, each of the ribs
340A, 340B may have a height
H4 of between 3 mm and 8 mm relative to the sloped surface
354 and, in some embodiments, have a height
H4 of 5.5 mm relative to the sloped surface
354. The charging contacts
322A, 322B may protrude above the sloped surface
354 the same distance or about the same distance as the charging contacts
222A, 222B protrude above the raised surface
252 (FIG. 5).
[0107] FIGS. 16 to
21 illustrate the robot
100 sequentially moving from the approach position
(FIG. 16) to the docked position
(FIG. 21). With reference to
FIGS. 14, 15 and
17, as the wheels
132 of the robot
100 first make contact with the dock platform
304, the cleaning module
143 in the front portion of the robot
100 engages and then rides up and along the first sloped surface
344 of the ribs
340A, 340B to raise the cleaning module
143 upward over the platform
304. With reference to
FIGS. 14, 15, 18 and
19, as the robot
100 continues to drive up the dock
300, the cleaning module
143 engages and rides along the raised surfaces
342 of the ribs
340A, 340B. This keeps the cleaning module
143 raised above the charging contacts
322A, 322B as the cleaning module
143 passes the charging contacts
322A, 322B.
[0108] With reference to
FIGS. 14,15, 20 and
21, after the cleaning module
143 has passed the charging contacts
322A, 322B, the cleaning module
143 rides down the second sloped surfaces
346 of the ribs
340A, 340B. As a result, the robot
100 including the cleaning module
143 descends onto the dock platform
304. In the docked position shown in
FIG. 21, the dock charging contacts
322A, 322B engage the robot charging contacts
164A, 164B. In the docked position, the robot wheels
132 are held in the wheel wells
149A, 149B.
[0109] Referring to
FIG. 3, first and second recesses or pockets
180A, 180B are formed in the bottom
114 of the robot housing. The first pocket
180A is sized and positioned to receive the first rib
140A and the second pocket
180B is sized and positioned to receive the second rib
140B when the robot is in the docked position. The first pocket
180A may be adjacent the left robot wheel
132 and the second pocket
180B may be adjacent the right robot wheel
132.
[0110] When the robot is deployed from the docked position, the ribs
340A, 340B cause the robot and its components to move in the reverse of the above-described motion. Thus, when the robot
100 is deployed, the cleaning module
143 is raised above the dock charging contacts
322A, 322B as the cleaning module
143 engage the ribs
340A, 340B.
[0111] The cleaning module
143 is located at the front of the robot
100 and at ground level, and therefore has the potential to scrape against the dock charging contacts
322A, 322B as the robot
100 approaches its charging or docked position, thereby posing a risk to the longevity of the charging contacts
322A, 222B. The present inventors addressed this problem by including the ribs
340A, 340B on the dock platform
304 such that the cleaning module
143 is lifted up and over the charging contacts
322A, 322B as described above.
[0112] The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although a few exemplary embodiments of this invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention. Therefore, it is to be understood that the foregoing is illustrative of the present invention and is not to be construed as limited to the specific embodiments disclosed, and that modifications to the disclosed embodiments, as well as other embodiments, are intended to be included within the scope of the invention.
EMBODIMENTS
[0113] Although the present invention is defined in the attached claims, it should be understood that the present invention can also (alternatively) be defined in accordance with the following embodiments:
- 1. A mobile robot system comprising:
a docking station comprising:
a platform having a front and a rear;
first and second raised charging contacts on the platform; and
first and second ramp features on the platform; and
a mobile robot comprising:
a housing;
a motorized drive system connected to the housing and including first and second drive wheels;
first and second charging contacts on a bottom of the housing; and
a cleaning module comprising at least one rotatable cleaning head that extends below the bottom of the housing;
wherein the mobile robot is movable from an approach position with the mobile robot spaced apart from the front of the platform to a docked position with the mobile robot on the platform and the docking station charging contacts engaged with the mobile robot charging contacts;
wherein, as the mobile robot moves from the approach position to the docked position, the mobile robot engages the first and second ramp features and the cleaning module is lifted over the docking station charging contacts.
- 2. The system of embodiment 1 wherein as the mobile robot moves from the approach position to the docked position, the first drive wheel engages the first ramp feature and the second drive wheel engages the second ramp feature.
- 3. The system of embodiment 1 wherein:
the platform comprises a first track on a left side portion of the platform and a second track on a right side portion of the platform;
the first ramp feature comprises a first ramp on the first track; and
the second ramp feature comprises a second ramp on the second track.
- 4. The system of embodiment 3 wherein each of the first and second ramps is positioned closer to the front of the platform than the rear of the platform.
- 5. The system of embodiment 3 wherein each of the first and second ramps comprises a raised flat surface, a first sloped surface, and a second sloped surface with the first sloped surface extending from the raised flat surface downwardly toward the front of the platform and the second sloped surface extending downwardly from the raised flat surface toward the rear of the platform.
- 6. The system of embodiment 5 wherein the bottom of the housing is spaced apart from the raised flat surfaces of each of the first and second ramps when the mobile robot is in the docked position.
- 7. The system of embodiment 5 wherein:
the left side portion of the platform includes a second flat surface extending from the second sloped surface to the rear of the platform; and
the right side portion of the platform includes a second flat surface extending from the second sloped surface to the rear of the platform.
- 8. The system of embodiment 7 wherein:
the platform includes a central portion between the left and right side portions;
the central portion includes a raised surface and a first sloped surface with the first sloped surface extending downwardly from the raised surface toward the front of the platform;
the docking station first and second charging contacts are on the raised surface of the central portion of the platform; and
the raised surface of the central portion of the platform is positioned vertically above the second sloped surfaces of each of the first and second ramps and/or the second flat surfaces of each of the left and right side portions of the platform.
- 9. The system of embodiment 8 wherein the central portion of the platform includes a second sloped surface and a second flat surface with the second sloped surface extending downwardly from the raised surface to the second flat surface and the second flat surface extending from the second sloped surface toward the rear of the platform.
- 10. The system of embodiment 9 wherein, in the docked position:
the left wheel is on the second sloped surface of the first ramp and/or the second flat surface of the left side portion of the platform;
the right wheel is on the second sloped surface of the second ramp and/or the second flat surface of the right side portion of the platform; and
the cleaning module is on or over the second flat surface of the central portion of the platform.
- 11. The system of embodiment 1 wherein as the mobile robot moves from the approach position to the docked position, the cleaning module engages each of the first and second ramp features.
- 12. The system of embodiment 11 wherein the first and second ramp features comprise first and second ribs, respectively, that each protrude upwardly from the platform.
- 13. The system of embodiment 12 wherein each of the first and second ribs comprise a raised flat surface, a first sloped surface, and a second sloped surface with the first sloped surface extending from the raised flat surface downwardly toward the front of the platform and the second sloped surface extending downwardly from the raised flat surface toward the rear of the platform.
- 14. The system of embodiment 12 wherein:
the platform comprises a first track on a left side portion of the platform and a second track on a right side portion of the platform;
the first rib is between the first charging contact of the docking station and the first track; and
the second rib is between the second charging contact of the docking station and the second track.
- 15. The system of embodiment 14 wherein:
a first depressed wheel well is defined in the first track and a second depressed wheel well is defined in the second track; and
in the docked position, the first wheel is received in the first depressed wheel well and the second wheel is received in the second depressed wheel well.
- 16. The system of embodiment 12 wherein:
the mobile robot comprises first and second recessed pockets in the bottom of the housing; and
in the docked position, the first rib is received in the first recessed pocket and the second rib is received in the second recessed pocket.
- 17. The system of embodiment 15 wherein the first recessed pocket is adjacent the first wheel and the second recessed pocket is adjacent the second wheel.
- 18. The system of embodiment 1 wherein:
the mobile robot is movable from the docket position to a deployed position with the mobile robot spaced apart from the front of the platform;
as the mobile robot moves from the docked position to the deployed position, the mobile robot engages the first and second ramp features and the cleaning module is lifted over the docking station charging contacts.
- 19. The system of embodiment 1 wherein, in the docked position, the cleaning module is positioned between the docking station charging contacts and the rear of the platform.
- 20. A method for docking a mobile cleaning robot with a docking station, the method comprising:
advancing the mobile cleaning robot onto a platform of the docking station;
while advancing the mobile cleaning robot onto the platform of the docking station, lifting a cleaning mechanism that extends below a bottom of a housing of the robot over at least one charging contact on the platform by advancing the robot over at least one elongated ramp feature on the platform; and
docking the robot in a docked position on the platform with at least one charging contact on the bottom of the housing of the robot engaging the at least one charging contact on the platform and with the cleaning mechanism positioned between the at least one charging contact on the platform and a rear of the platform.