Coverage robot mobility

This application is under the name "ROBOT NETWORKLING, THEMING AND COMMUNICATION SYSTEM" filed on December 2, 2005, and is subject to 35 USC 119 for a US provisional patent application assigned application number 60 / 741,442. Priority is claimed under section (e) and the entire content of the application is incorporated herein by reference in its entirety.

The present invention relates to a robot, and more specifically to an autonomous coverage robot.

An autonomous robot is a robot that can perform a desired task in a non-structural environment without constant guidance by humans. Many types of robots are to some extent autonomous. Different robots can be autonomous in different ways. Autonomous coverage robots traverse work surfaces without constant guidance by humans to perform one or more tasks. In the field of home, office, and / or consumer robot systems, mobile robots perform household chores such as vacuuming, floor washing, patrols, lawnmowers, and other such tasks. Has been widely adopted.

<p> The autonomous coverage robot encounters many obstacles during operation. The robot must constantly avoid obstacles to continue its operation, and must escape on its own if caught by fabric, string, or other entwined soft medium.</p><p> In one aspect, the autonomous coverage robot is a chassis, a drive system mounted on the chassis and configured to steer the robot, an edge cleaning head supported by the chassis, and a control device supported by the chassis. And. The edge cleaning head is driven by an edge cleaning head motor and can rotate about a non-horizontal axis. The edge cleaning head extends beyond the lateral length of the chassis to engage the floor surface while the robot is maneuvering across the floor. The edge cleaning head may be located on or near the periphery of the robot. The brush control process by the controller controlling the robot operation is configured to monitor the motor current associated with the edge cleaning head separately from the drive process. Also, the brush control process by the controller is at the same speed as the rewinding cord, string, or other entangled medium after the detection of a spike (eg, transient or rapid increase in motor current) or generally high motor current motor. The edge cleaning head motor is configured to reverse bias in the opposite direction of the previous cleaning direction (so that it rotates substantially neutral and / or is driven to rotate), on the other hand the floor. Continue to steer the robot across and perform uninterrupted floor coverage or cleaning, or perform other motion actions. In one embodiment, the brush control process by the controller follows a high edge cleaning head motor current (at the same speed as the rewinding cord, string, or other entangled medium, rotating substantially neutral. And / or reverse bias the edge cleaning head motor (to be driven to rotate), and subsequently or in parallel, either directly or indirectly through the supervision process, the robot substantially A signal is transmitted to the drive motor control process so that rewinding can occur at the same time as moving backward, changing the drive direction, and advancing the robot.</p><p> In one embodiment, the edge cleaning head comprises a brush with bristles extending beyond the periphery of the chassis. In one embodiment, the edge cleaning head comprises at least one brush element having first and second ends, which rotate perpendicular to the working surface around the first end. Define the axis. The edge cleaning head is rotatable about a substantially vertical axis. In one case, the edge cleaning head comprises three brush elements, each of which forms an angle of approximately 120 degrees with the adjacent brush element. In another case, the edge cleaning head comprises six brush elements, each of which forms an angle of approximately 60 degrees with an adjacent brush element.</p><p> In another embodiment, the edge cleaning head comprises a rotatable drainer that extends beyond the periphery of the chassis. This rotatable drainer can be used for washing with water, surface treatment, and the like.</p><p> In yet another embodiment, the edge cleaning head comprises a plurality of adsorption fibers that extend beyond the periphery of the chassis as the cleaning head rotates. The multiple adsorbent fibers can be used like a mop to wipe spills, clean the floor, apply surface treatments, and so on.</p><p> The robot comprises a plurality of cleaning heads (eg, two or three) supported by a chassis. In one embodiment, the robot further comprises a main cleaning head carried by the chassis, the cleaning head extending across a swath covered by the robot, which forms the robot's main working width, and cleaning. The head can be driven to rotate about a horizontal axis so that it engages the floor surface while the robot is maneuvering across the floor. The main cleaning head may include a cylindrical body that defines a longitudinal axis of rotation parallel to the working surface, bristles arranged on the cylindrical body, and flexible flaps arranged longitudinally along the cylindrical body. The brush control process by the controller rotates and / or rotates substantially neutral at the same speed as the rewinding cord, string, or other entangled medium in response to a high main cleaning head motor current. It is configured to reverse bias the rotation of the main cleaning head (so that it is driven), while the motion control process continues to steer the robot separately across the floor. In another embodiment, the robot is carried by a chassis and driven to rotate about a horizontal axis so that the robot engages the floor surface while maneuvering across the floor. Equipped with. The two main cleaning brushes can be driven to rotate in the same or opposite directions.</p><p> In another aspect, a method of disentangled the autonomous coverage robot comprises placing the robot on a floor surface, the robot being carried by a chassis and driven by an edge cleaning head motor. Autonomously crosses the floor surface in the forward direction of the robot while rotating the robot around a non-horizontal axis. The edge cleaning head extends beyond the lateral length of the chassis and engages the floor surface. The robot rotates substantially neutral (at the same speed as the rewinding cord, string, or other entangled medium) in response to a high edge cleaning head motor current while continuing to maneuver across the floor surface. And / or to be driven to rotate), separately apply a reverse bias to the edge cleaning head motor.</p><p> In one embodiment, the brush control process by the robotic controller is forward (apart from robot motion control) before reversing the rotation of the edge cleaning head in response to a high cleaning head motor current. Determine the movement of the robot. The robot's brush control process can reverse the rotation of the edge cleaning head (apart from robot motion control) in response to a high edge cleaning head motor current over a period of time. In one embodiment, after the brush control process reverses the rotation of the edge cleaning head, the brush control process moves in the opposite direction, changes drive direction, and changes direction, either directly or through a supervision process. A signal can be sent to the robot's motion control process to move in that driving direction.</p><p> In another embodiment, the robot also comprises a main cleaning brush carried by the chassis, which brushes around the horizontal axis such that it engages the floor surface while the robot is maneuvering across the floor. It can be driven to rotate. The robot separately reverses the rotation of the main cleaning brush in response to the high main cleaning head motor current while continuing to maneuver across the floor surface. The robot's brush cleaning process can also determine the forward movement of the robot in response to a high primary cleaning brush motor current before separately reversing the rotation of the primary cleaning brush. In addition, the robot's brush cleaning process can also reverse the rotation of the main cleaning brush for a period of time or intervals.</p><p> In another aspect, the autonomous coverage robot comprises a drive system, a collision sensor, and a proximity sensor. The drive system is configured to steer the robot according to directional (turning) and speed settings. The collision sensor responds to the robot's collision with an obstacle in the forward direction. The proximity sensor responds to obstacles in front of the robot at a distance that is close but not in contact with the robot, eg, 1-10 inches, preferably 1-4 inches. The drive system motion control process also speeds in response to signals from proximity sensors indicating the detection of potential obstacles during the cleaning or coverage process, including advancing the robot according to directional settings. Can be configured to reduce. Further, the motion control process of the drive system may also be configured to change the directional (turning) setting in response to a signal received from a collision sensor indicating contact with an obstacle.</p><p> In some cases, the drive system motion control process changes the directional setting in response to signals received from the collision sensor and one or more side proximity sensors to follow the surroundings of the obstacle. Can be configured as In other cases, the drive system may be configured to change the directional (turning) setting in response to signals received from collision and proximity sensors to guide the robot away from obstacles. In one embodiment, the drive system is configured to steer the robot in torque (eg, motor current or motor resistance) settings, and the drive system responds to signals received from collision sensors that indicate contact with obstacles. It is configured to change the motor current or motor resistance setting. The drive system can increase the motor current or motor resistance setting in response to a signal received from a collision sensor indicating contact with an obstacle.</p><p> Proximity sensors are directed to each other to focus at a fixed distance from each other, as substantially disclosed in US Pat. No. 6,594,844, "Robot obstacle detection system," which is incorporated herein by reference in its entirety. It can comprise a plurality of pairs of at least one pair of infrared emitters and receivers. Alternatively, the proximity sensor may include a sound detector device. Collision sensors can include switches, capacitive sensors, or other contact sensing devices.</p><p> The robot can be placed on the floor. In yet another aspect, the method of maneuvering the autonomous coverage robot against an object on the floor comprises the step of the robot autonomously traversing the floor at full speed cleaning speed in cleaning mode. When it senses the proximity of an object in front of the robot, the robot slows down the cleaning speed to a slower cleaning speed while the robot continues towards the object until it detects contact with the object. Upon sensing contact with the object, the robot optionally turns with respect to the object at a substantially slower cleaning speed, while cleaning in the vicinity of the object. The robot can follow around the object and, on the other hand, clean in the vicinity of the object. When the robot leaves the surroundings, the robot can increase its speed to full speed cleaning speed. The robot can maintain a substantially constant follow-up distance from the object, a follow-up distance less than the length of the edge cleaning head or brush extending beyond the follow-up side of the robot body, or the first with the object. In response to contact at the decelerated cleaning speed of, it is possible to substantially contact the object while cleaning in the vicinity of the object. In one embodiment, the follow-up distance from the object is essentially the distance between the robot and the object immediately after it comes into substantial contact with the object. In another embodiment, the follow-up distance from the object is between about 0 and 2 inches.</p><p> In one case, the robot performs maneuvers to move around the object in response to contact with the object. This maneuver may include the robot moving around the object in a substantially semi-circular path or in a continuous alternating partial helix (eg, an arc with a diminishing radius). Alternatively, this maneuver may include moving the robot away from the object and then in a direction that is substantially in direct contact with the object.</p><p> Sensing the proximity of an object in front of the robot allows the robot to decelerate from full speed to decelerated cleaning speed at a constant rate, an exponential rate, a non-linear rate, or some other rate. .. In addition, the robot can reduce the torque (eg, motor current) setting of the drive motor, main brush motor, or side brush motor when it senses contact with an object.</p><p> In yet another aspect, the autonomous robot is configured to detect the chassis, a drive system mounted on the chassis and configured to steer the robot, and a chassis-supported floor surface below the robot. It is equipped with a floor proximity sensor. The floor proximity sensor is a beam emitter configured to direct the beam towards the floor surface and a beam mounted inside the chassis' downward socket in response to the guided beam's reflection from the floor surface. It is equipped with a light receiver. The floor proximity sensor can be a substantially sealed unit (eg, downwards) to prevent the buildup of deposits, "carpet fluff", hair, or household dust inside the socket. Also, a beam transmission lid having anterior and posterior edges arranged across the lower end of the socket may be provided. The lid may include a lens made of antistatic material. The front edge of the lid at the front edge of the robot, i.e., the edge of the lid in the direction of movement of the robot, is higher than the rear edge. The lower surface of the socket can be shaped like a wedge. In one embodiment, the floor proximity sensor is described in US Pat. No. 6,594,844, "Robot obstacle detection. Includes at least one pair of infrared emitters and receivers, as substantially disclosed in "system".</p><p> In one embodiment, the robot drive system comprises at least one driven wheel suspended from the chassis and at least one floor-wheel proximity sensor carried by the chassis and housed adjacent to one of the wheels. The floor-wheel proximity sensor is configured to detect the floor surface adjacent to the wheels. The drive system may also include a control device configured to steer the robot away from the sensed cliff in response to a signal received from the floor proximity sensor. In some cases, the drive system is housed in close proximity to one of the wheels and comprises a derailment sensor that responds to a substantial downward displacement of the wheel with respect to the chassis. The drive system may include a verification system that verifies the operability of the floor proximity sensor when all wheels are derailed. This verification is based on the belief that all wheels were derailed as a result of the robot being lifted off the floor by humans, and not all floor proximity sensors are consistent with the floor surface. It is checked to confirm that it is not (reflection is not measured or reflection is too strong). Any sensor that matches the floor surface or excessively strong reflections (eg, indicating a blocked sensor) is considered to be disturbed. In response to this detection, the robot can initiate a maintenance reporting session indicating that the floor proximity sensor should be cleaned by a sign or light. In response to this detection, the robot prohibits forward movement until it is determined by the verification procedure that all floor proximity sensors have been cleaned and functioning. Each wheel-floor proximity sensor and de-wheel proximity sensor may include at least one pair of infrared light emitters and receivers.</p>

Similar numbers in different drawings refer to similar elements.

Detailed explanation FIGS. 1 to 3 show an upper perspective view, a lower perspective view, and an exploded view of an exemplary autonomous coverage robot 100. Robot 100 includes a chassis 102, a drive system 104, an edge cleaning head 106a, and a control device 108. The drive system 104 is mounted on the chassis 102 and is a differential drive device configured to steer the robot 100 (close to or above the center diameter of the robot and has a separately speed controllable left wheel). And the right wheel). The edge cleaning head 106a removes dirt and debris below and in the immediate vicinity of the robot 100, and more specifically, when the robot cleans forward, it removes dirt and debris from the cleaning path of the main cleaning head 106b. It is mounted so that it extends beyond the side edges of chassis 102 for sweeping in. In some embodiments, the main or edge cleaning heads 106b, 106a can also be used to apply surface treatments. Control 108 (also illustrated in FIG. 9A) is carried by chassis 102 and commands based on sensor readings or instructions to autonomously clean or process the floor, as described below. Is controlled by a code of conduct robot system that supplies the components of the robot 100. The storage battery 109 can be a power source for the robot 100 and its subsystems. The bottom lid 110 can protect the inner part of the robot 100 and keep out dirt and debris.

The drive system 104 comprises a left drive wheel assembly 112, a right drive wheel assembly 114, and a leg wheel assembly 116. The drive wheel assemblies 112, 114 and the leg wheel assemblies 116 are coupled to the chassis 102 to serve as a support for the robot 106. The control device 108 can supply a command to the drive system to drive the wheels 112 and 114 forward or backward to steer the robot 100. For example, a command is sent by the controller to engage both wheel assemblies forward, resulting in a forward motion of the robot 100. In another case, a command can be sent for a left turn that engages the left wheel assembly 112 forward and on the other hand the right wheel assembly 114 is driven backwards, the robot 100 when viewed from above. Will turn clockwise.

4 and 5 show a front perspective view and an exploded view of the main cleaning brush 111 that can be incorporated into the main cleaning head 106b of the robot 100 by being attached to the chassis 102. As disclosed herein, the general construction of robots and cleaning heads is incorporated herein by reference in its entirety, unless otherwise noted. Similar to that disclosed in. In general, when a robot brush gets entangled with cords, strings, hair, edging, or tufts, the brush motor may encounter overcurrent or temperature rise, causing increased energy consumption of the brush, poor cleaning, deceleration, or locking. There is. If the robot is so controlled, or if the entanglement is heavy or fixed, the robot can be restrained in place and sensors can be used to detect stalemate. In some cases, it may stop working, which may prevent cleaning. If the robot gets stuck during its normal working process, the robot must be "rescued" and cleaned to continue its autonomous functioning. Theoretically, additional energy consumption is incurred to counter the static or dynamic friction of the drive wheels, leg wheels, trash drainers, and cleaning head drive trains (reverse drive). The edging / bunch / cord can be tightly wrapped around the minimum winding diameter of the cleaning brush (eg, if the brush 111 has only bristles, it is usually the core of the brush 111). If the minimum diameter of the cleaning brush 111 is solid (without elasticity), for example, when the brush is rotated counterclockwise inside the cleaning head to rewind the edging / decoration / cord Additional energy may be required to overcome static or dynamic friction on the brushes in contact with the rows and floor. If the tuft or string is left entangled around the brush, it may be necessary to remove the brush 111 from the cleaning head 106b to remove the entanglement. The main cleaning head 111 is a buff arranged along the cleaning head main body 117. It has a soft flap 113 and bristles 115. A soft flap 113 arranged along the length of the cleaning head body 117 can minimize static friction. The cleaning head body 117 is rotatable about its horizontal axis so that the cleaning head body engages the floor surface while the robot 100 is moving across the floor, on the baffle 113 and the bristles 115 on the floor surface. Stir possible dirt and debris. The control device 108 reverse biases the rotation of the main cleaning head 111 following a spike or increase in the main cleaning head motor current (ie, as the robot moves forward, it cleans as the robot pulls out and rewinds the entanglement. (Provides enough reverse current to allow free rotation of the brush), on the other hand, when the controller 108 performs individual motion control actions to move the robot 100 across the floor, a cleaning cycle or other Can be configured to continue running the cycle of. In this case, the edge 116 of the soft flap 113 can be the smallest diameter of the cleaning head 111. The edge 116 is flexible (flexible and soft) so that it requires very little energy to deform, potentially diversion of some of it from the energy required to initiate the movement of the robot 100. The temporary delay in the brush gear train that encounters static friction gives the robot 100 the opportunity to resume movement, thereby allowing the brushes to be easily disentangled. Similarly, the cord or ornament is a larger diameter of the rim 116 (a core such as a core 117 or a core or an ornament) simply because the brush 111 does not complete so many windings per unit length of the entangled cord or ornament. It can be less likely to get entangled around (compared to a thinner core). Furthermore, the lengthwise scooping (curving) nature of the flap 113 is between the robot being started and the temporary delay between the reverse bias that biases the reverse drive of the entangled cleaning head 111. In addition, it also acts as a spring that forcibly unwinds / releases the decorations / edges. Bristle 115 is mainly used for cleaning On the other hand, the flap 113 can be used primarily for the purpose of disentanglement. This allows the robot 100 to continue cleaning (carpet agitation) if the entangled string is eaten and held by the flap 113 within the cleaning head 111. Details and feature structures of other robots that can be combined with those described herein can be found in US Patent Application No. 60/747791 below, the entire contents of which are incorporated herein by reference.

6A and 6B show an upward perspective view and an exploded view of the edge cleaning head 106. The edge cleaning head 106a is supported by the chassis 102 and driven by the edge cleaning head motor 118 and the driving force transmitter 119 to rotate the brush 120 around a non-horizontal axis. The brush 120 has brush elements 122A-F extending beyond the periphery of the chassis 102. Each brush element 122A-F forms an angle of about 60 degrees with the adjacent brush element and is tipped with bristles extending along the axes of these elements. The brush 120 is rotatable about a vertical axis so that the ends of the brush elements 122A-F move at right angles to the work surface. The edge cleaning head 106 may be placed close to the edge of the robot 100 so that the brush 120 can sweep dirt and debris over the edge of the chassis 102. In some embodiments, the edge cleaning head 106 operates around an axis that is offset (tilted) from the robot's vertical axis. As shown in the schematic form in FIG. 6C, the brush 106 collects dust from the outside of the periphery of the robot toward the main work width, and once such collected dust comes to the main work surface, the dust is collected. It can be tilted forward and left and right (ie, about 45 degrees from the direction of movement inside the wheel contact plane, in order not to disturb such debris, or to expel debris from the robot's working width if it is not on the main work surface. Inclines downward with respect to the plane around the line). This misalignment can be optionally adjusted to individually correct the tilt of the cleaning head 106 to suit various carpet types such as fluff fabrics.

Other configurations of the edge cleaning head can also be used with the robot 100. For example, the edge cleaning head may have three equally spaced brush elements separated by 120 degrees. FIG. 7 shows another embodiment of the edge cleaning head 124 in which the rotatable drainer 126 is used in place of the brush. In other configurations, the edge cleaning head has one or more adsorption fibers that extend beyond the perimeter of the chassis 102.

FIG. 8A shows a bumper 130 that can be used in the autonomous exhaustive robot 100. FIG. 8B shows a proximity sensor 134 that can be housed inside the bumper 130. The drive system 104 may be configured to steer the robot 100 according to directional and speed settings. Proximity sensor 134 can detect potential obstacles in front of the robot.

FIG. 9A is a schematic diagram of the electronic device of the robot 100. The robot 100 includes an omnidirectional receiver, a directional receiver, a wall proximity sensor 134, and a control device 103 that communicates with a bumper microcontroller 107A that simultaneously controls the bumper switch 132. Control 103 monitors all other sensor inputs, including the cliff sensor 140 and the motor current sensor for each motor.

Control of the direction and speed of the robot 100 is incorporated herein by reference in its entirety to reduce the magnitude of the speed of the robot 100 when the proximity sensor 134 detects a potential obstacle. By motion control actions selected by the arbiter (and performed by controller 108) according to the principles of code-of-concept robotic systems for coverage and scope, generally disclosed in 6809490 and 6781338. Can be dealt with. The motion action executed by the control device 108 can also change the speed of the robot 100 when the motion impact sensor 132 detects a collision of the robot 100 with an obstacle. Therefore, referring to FIG. 9A, the robot 100 traverses the floor surface by performing a cruising or linear action 900. When the robot 100 detects by the proximity sensor 134 that it is in close proximity but has not yet touched an obstacle, the robot 100 may perform a flexible contact routine 902 (which may be one action or one of the actions). It may be a part or formed by more than one action), but in that routine, the robot 100 does not rush into the obstacle at full speed cleaning speed and the collision actually occurs. Sometimes, the control device 108 reduces the robot's approach speed towards potential obstacles from a full-speed cleaning speed of about 300 mm / sec so that the collision noise is less and the collision is less likely to damage the surface. Reduce to a deceleration cleaning speed of 100 mm / sec. Overall noise, potential damage to robot 100 or objects collided by this robot is reduced. When the robot 100 detects contact with an object by the motion impact sensor 132, the robot 100 performs the following routines: bouncing 910, following around an obstacle 912, changing the driving direction and moving away from the object 914. Or, perform one of the routines of turning and changing the driving direction so that it is close to and follows an object (eg, a wall). The bouncing 910 follows the object It inevitably involves the robot 100 moving as if it bounces. The 912 that follows the perimeter of the object is such that the robot 100 follows the perimeter of the object at a predetermined distance, for example, to clean the vicinity of the object and / or to the wall. It is inevitably accompanied by the use of sensor 134. Robot 100 continuously cleans the room, and when the robot detects an object in front of it, which can be a wall, table, chair, sofa, or other obstacle, the robot is decelerated. However, continue cleaning in the same direction without interruption. At given and / or random, Robot 100 essentially slows down cleaning speeds so that the side / edge brush 106a collects debris or dirt from the corners between the floor and walls or obstacles. , Collides with an object, turns at a predetermined position so that the edge of the main cleaning head 106b is as close to the wall as possible, and closely follows the object in contact with the side surface of the robot. Once the robot 100 has left the wall, after a predetermined and / or randomized distance within a predetermined limit, the robot 100 increases its speed to full speed cleaning speed. In other cases, the robot collides with an object, turns in place until it faces away from the object or wall, and immediately moves away from the object or wall at full speed cleaning speed. Collide with an object at essentially slower cleaning speeds to collect debris or dirt, swivel in place so that the edges of the main cleaning head 106b are as close to the wall as possible, and on the sides of the robot. Closely follow objects in contact. Once the robot 100 has left the wall, after a predetermined and / or randomized distance within a predetermined limit, the robot 100 increases its speed to full speed cleaning speed. In other cases, the robot collides with an object, turns in place until it faces away from the object or wall, and immediately moves away from the object or wall at full speed cleaning speed. Collide with an object at essentially slower cleaning speeds to collect debris or dirt, swivel in place so that the edges of the main cleaning head 106b are as close to the wall as possible, and on the sides of the robot. Closely follow objects in contact. Once the robot 100 has left the wall, after a predetermined and / or randomized distance within a predetermined limit, the robot 100 increases its speed to full speed cleaning speed. In other cases, the robot collides with an object, turns in place until it faces away from the object or wall, and immediately moves away from the object or wall at full speed cleaning speed.

Robot 100 uses the behavioral software architecture inside controller 103. While the Robot 100 embodiments discussed herein have only partial or no use of code of conduct control, the code of conduct control allows the robot to be robust (ie, stuck or broken). It is effective not only (not) but also in controlling it to be safe. Robot 100 uses a control and software architecture with several actions performed by the arbiter in control device 103. The action is input to the arbiter in response to the sensor event. In one embodiment, all actions have fixed relative priorities to each other. The arbiter (in this case) recognizes the enablement condition, the action has a complete set of enablement conditions, and the arbiter selects the action with the highest priority among the actions that meet the enablement condition. To do. In descending order of priority, actions are generally as escape and / or avoidance actions (such as avoiding cliffs or escaping corners), and working actions (eg, wall following, momentum, or linear drive). being classified. Actions include various escapes (corner escape, valley descent prevention, stuck situations, eg, "ballistic" temporary fire-and-forgets that deter some evasive actions as disclosed in US Pat. No. 6,809,490. Includes get movement), cliff avoidance, virtual wall avoidance (virtual wall can be a beacon with a gateway beam), spot coverage (covered with a limited pattern such as a spiral or tillage format patch), alignment (obstacles) Forward obstacles encountered while following an object, such as a side proximity sensor or bumper that extends to the side of the robot, turning in place using a side proximity sensor to align with the inner corner. Use to respond to a collision to "bounce" (the action that occurs after the robot collides with an object), which represents either or both of substantially parallel tracking and collision tracking along an obstacle. And operation (cruising) can be included. Prioritize actions Some kind of robot operation is performed during the determination. If more than one action is present in the arbiter, the action with the higher priority will be performed as long as any corresponding requirement is met. For example, a cliff avoidance action will not be executed unless the cliff is detected by the cliff detection sensor, but the execution of the cliff avoidance action always takes precedence over the execution of other actions that also meet the enablement conditions. The ranking is high.

Reactive behavior involves the detection of various sensors and phenomena as its enablement conditions or triggers. These include obstacle avoidance such as forward proximity detection (double), forward collision detection (double), cliff sensor (double), and detection of virtual wall signals (which can be thought of as exhaustive triggers). And sensors for detection are included. These types of sensors are monitored and conditioned by filters, conditioning, and their drivers, but these sensors not only generate enablement conditions, but also help behaviors work predictably, and all. For available information (eg, conversion to 1-bit "correct / incorrect" signals, recording of expected angles of collision or event based on intensity or time difference from sensors, or history, average, frequency, or variation information). Data can also be recorded.

The actual physical sensor can be displayed in the architecture by a "virtual" sensor synthesized from conditioning and drivers. Proprietary or proprioceptive with respect to robot 100 such as motor overcurrent, robot 100 stationary or stuck situation (by monitoring the lack of mileage readings from the wheel encoder or counter), battery charge by coulometric analysis. Additional "virtual" sensors, as well as other virtual sensors, synthesized from interpreted, detectable or interpreted physical properties.

In addition, reactive behaviors can be performed according to enablement conditions that represent detection phenomena that should be tracked or followed. A beam or radio (RF, acoustic) signal can be detected without instruction or in some cases as indicated. A remote beam or indicator (bar code, back-reflective marker, characteristic marker, reference marker, or visually recognized natural marker) that gives instructions allows for homing or relative movement, but without instruction. Robot 100 can transition to servo mechanism control based on the presence, absence, and / or relative intensity of the detection signal. Reflections of beams, edges, or lines from the robot 100 can be detected as well, and follow-up actions (such as obstacle tracking by the robot 100) are performed by servo mechanism control based on such signals. A debris or artifact signal can be collected by monitoring the debris or crossing objects collected by the robot, and this signal can be a enablement condition for reactive behaviors that control the spot coverage pattern.

Robot 100 maintains a concurrency process, or "parallel" process, which is not generally considered to be reactive behavior. A scheduler may be needed to allocate processor time to most other processes (including, for example, arbiters and actions) in a collaborative or other multitasking manner. The more threading available, the fewer processes can be managed by the scheduler. As noted, filters and conditioning as well as drivers can interpret and translate the raw signal. These processes are not considered reactive behaviors and do not provide direct control over the motor drive or other actuators. Further, in this embodiment, the main brush and the side brushes can be otherwise controlled by dedicated brush behavior and brush control arbiters, but one or more brush motor controllers control these brushes.

According to another embodiment, the flexible contact routine 902 uses an infrared proximity detector 134 that should operate at about 1 to 10 inches (preferably 1 to 4 inches) (ie, the receivers face each other). When receiving from reflected light generated in the overlapping space of the angled light emitters and receivers). This distance is chosen to be within the effective range of the IR proximity or cross beam sensor 134, but within a range that has sufficient time to decelerate the mobile robot 100 before colliding with the detection obstacle. .. Whereas conventional proximity sensors reflect signal intensities in response to obstacle albedos, crossed beam signals 134 are a variety of crossing beam / regions of the photophore and photophore that penetrate within a particular distance from the sensor. Can be threshold limited with respect to albedo. In addition, proximity-detected wall-based deceleration can be suppressed or interrupted by the user, separate from the collision sensor 132. The control device 108 can slow down the robot's descent in a substantially stable manner and then slowly cruise it. The controller 108 is capable of slowly performing S-curves beyond about 3 inches and can be decelerated in a stable manner, but at acceleration or deceleration rates greater than about 3 inches. During escape behaviors such as panic, rest, stuck, valley descent prevention, the robot is essentially by not using proximity sensor 134 as a possible condition for any escape behavior or some avoidance behavior. The proximity sensor 134 can be disconnected.

The drive system 104 reduces the speed setting in response to a signal from the proximity sensor 134 indicating the detection of a forward obstacle, while advancing the robot 100 according to the current directional setting to continue working on the floor or surface. It can be configured as follows. The drive system 104 can be configured to change the directional setting in response to a signal received from a collision sensor 132 indicating contact with an obstacle. For example, the drive system 104 can be configured to change the directional setting in response to signals received from the collision sensor 132 and the proximity sensor 134 so that the robot 100 follows around an obstacle. In another embodiment, the drive system 104 can be configured to reorient to guide the robot 104 away from obstacles.

Proximity sensor 134 may include one or more pairs of infrared emitters and receivers. For example, modulated photophore and standard photophore can be used. Light pipes (not shown), collimating or diffuse optics, Fresnel or diffractive optics are more uniform or more focused or more detectable in high probability / high collision areas such as in the immediate direction. It can be used in several embodiments to eliminate blind spots by supplying a highly potent optical pattern. Alternatively, some embodiments may utilize sound wave detectors or other types of proximity sensors.

In some embodiments, the motion collision sensor 132 may include a mechanical switch 130. In some embodiments, the collision sensor 132 may include a capacitive sensor. Other types of contact sensors can be used as well.

The drive system 104 can be configured to steer the robot 100 at a torque (or motor current) setting in response to a signal received from a collision sensor 132 indicating contact with an obstacle. For example, the drive system 104 can increase torque (or motor current) in response to a signal received from a collision sensor indicating contact with an obstacle.

In another embodiment of how to steer an autonomous exhaustive robot against an object on the floor, the robot 100 can be first placed on the floor (or, for example, the robot can be placed from the charging dock). (It may already be on the floor when departing), the robot 100 autonomously traverses the floor at full speed cleaning speed in cleaning mode. If the robot 100 detects a nearby object in front of the robot 100, the robot slows down the cleaning speed (for example, up to the decelerated cleaning speed) and detects a collision that is likely to be with this object but could be another object. Continue moving towards the object and continue working / cleaning the floor until you do. When detecting a collision with an object, the robot 100 swivels relative to the object so that it collides with the object and is adjacent to it, i.e., cleaning along it. For example, the robot 100 can follow around an object and, on the other hand, clean along or adjacent to the object. In another case, the robot 100 can maintain a certain follow-up distance from the object while cleaning adjacent to the object in response to contact with the object. The follow-up distance from the object can be the distance between the robot 100 and the object immediately after contact with the object, for example 0 to 2 inches. This distance is optionally less than the distance that the side or edge brush unit 106a extends beyond the sides of the robot.

In some cases, the robot 100 steers around the object in response to contact with the object. For example, the robot 100 can follow a somewhat semicircular path around an object or move in a continuous alternating partial helix (eg, an arc with a diminishing radius). In another case, the robot 100 can move away from the object and then move in a direction that is somewhat tangential to the object.

Robot 100 can reduce the cleaning speed to a deceleration speed at a constant rate, eg, at a non-linear or exponential rate. The full speed cleaning speed of the robot 100 may be about 300 mm / sec, and the deceleration cleaning speed of the robot 100 may be about 100 mm / sec.

FIG. 10 is a motion collision sensor 132, a floor proximity sensor 140, and a mounting fastener 142 that can be used by the robot 100 to detect adjacent floors. The motion collision sensor 132 can detect a collision between the robot 100 and an object in the robot's forward path. The floor proximity sensor is carried by the chassis 102 and can be used to detect when the robot 100 approaches a pair of stair-like "cliffs". The floor proximity sensor 140 can send a signal to the control device 108 indicating whether or not the cliff is detected. Based on the signal from the floor proximity sensor 140, the controller 108 can instruct the drive system 104 to change speed or speed to avoid cliffs.

11 and 12 show a side view and an exploded view of the floor proximity sensor 140. The floor proximity sensor 140 has a body with a front portion 144, a rear portion 146, a light emitter 148, a receiver 150, and a lid 152. The light emitter 148 and the receiver 150 may be capable of emitting and receiving infrared light. The light emitter 148 and the light receiver 150 are arranged at an angle inside the front and rear body portions 144, 146 so that their axes are aligned at a point directly below the robot 100, which is approximately the floor distance. To.

FIG. 13 shows an exploded view of the lid 152. The lid 152 includes a lens 154 and a lid body 156. The lens 152 may be transparent to infrared light, and the lid body 156 may be opaque to facilitate focusing of the light emitted from the light emitter 148. The front edge 158 of the lid 152 helps reduce dust buildup and primarily when the sensor 140 is accurately positioned above the floor, light is received by the receiver 150 and the sensor 140 " It is higher than the posterior edge 159 of this lid to ensure that the reduced amount is received when above the "cliff". In some embodiments, the lid 152 is made of antistatic polycarbonate, copper oxide-doped or coated polycarbonate, General. Materials with antistatic (dissipative or conductive) properties, such as antistatic Lexan "LNP", antistatic polyethylene, antistatic ABS / polycarbonate alloys, or other similar materials available from Electric, Inc. Made using. One example comprises ABS747 and PC114R or 1250Y mixed with antistatic powder. Preferably, the robot shell, chassis, and other components, at least in part, are antistatic (eg, antistatic ABS), dissipative, and / or conductive to ground the antistatic lid 152. is there. The lid 152 can also be grounded by any conductive path. When the exhaustive robot 100 traverses the floor, the lid 152, which does not have antistatic properties, can be charged with static electricity (eg, by friction), thereby removing debris charged to the opposite polarity, such as fluff. Although it has a tendency to accumulate, it can interfere with the sensing field of view of the light emitter 148 and the receiver 150.

When the floor proximity sensor 140 is properly placed on the floor, the light emitted from the light emitter 148 is reflected off the floor and returned to the receiver 150 to be a signal readable by the controller 108. If the floor proximity sensor 140 is not above the floor, the amount of light received by the receiver 150 is reduced to a signal that can be interpreted as a cliff by the controller 108.

FIG. 14 is an exploded view showing an embodiment of the leg ring assembly 116. The leg wheel assembly 116 is individually removable from the chassis 102 and the exhaustive robot 100. The leg ring assembly 116 comprises a leg ring housing 162, a leg ring 164, a derailment sensor 166, and a wheel-floor proximity sensor 168.

The leg ring housing 162 carries a leg ring 164, a wheel removal sensor 866, and a wheel-floor proximity sensor 168. The leg ring 164 turns around a vertical axis and rolls around a horizontal axis of the leg wheel housing 162.

The derailment sensor 166 detects the downward displacement of the leg wheel 164 with respect to the chassis 102. The wheel removal sensor 166 determines whether the leg wheel 164 is in contact with the work surface.

The wheel-floor proximity sensor 168 is housed adjacent to the leg wheel 164. The wheel-floor proximity sensor 168 detects the proximity of the floor to the chassis 102. The ring-floor proximity sensor 168 includes an infrared (IR) light emitter and an IR receiver. The IR light emitter produces an IR signal. IR signals are reflected from the work surface. The IR receiver detects the reflected IR signal to determine the proximity of the work surface. Alternatively, the wheel-floor proximity sensor 168 may use another type of sensor, such as a visible light sensor. The wheel-floor proximity sensor 808 prevents the exhaustive robot 100 from falling from a cliff in the work surface, such as a staircase or shelf. In some embodiments, the drive theory assemblies 114, 116 each include a wheel-floor proximity sensor.

FIG. 15 is an exploded assembly view showing an embodiment of the derailment sensor 166. The derailment sensor 806 includes an IR light emitter 170 and an IR receiver 172 in a housing 173. The IR light emitter 170 produces an IR signal. The IR signal is reflected from the pedestal 164. The IR receiver 172 detects the reflected IR signal and determines the vertical position of the leg ring 164.

FIG. 16 is a cross-sectional view showing an embodiment of the leg ring assembly 116. This figure shows the upper surface 174 of the pedestal 164 on which the IR signal is reflected. The IR receiver 172 uses the reflected IR signal to determine the vertical position of the leg ring 164.

In some cases, the drive system 104 may further include a verification system that verifies the maneuverability of the floor proximity sensor when all wheels are derailed. This verification is based on the belief that all wheels were derailed as a result of the robot being lifted off the floor by humans, and not all floor proximity sensors are consistent with the floor surface. It is inspected to confirm that it is not (reflection is not measured or reflection is too strong). Any sensor that matches the floor surface or excessively strong reflections (eg, indicating a blocked sensor) is considered to be disturbed. In response to this detection, the robot can initiate a maintenance reporting session with a sign or light indicating that the floor proximity sensor should be cleaned. In response to this detection, the robot prohibits forward movement until it is determined by the verification procedure that all floor proximity sensors have been cleaned and functioning. For example, a mechanical switch sensor can be positioned at a location 176 above the pedestal 168, which closes the sensor when the pedestal is pushed in (eg, when it is pushed up by the floor). It supplies the controller 108 with an alternation signal that the pedestal 164 is on the floor.

In some cases, autonomous exhaustive robots can become entangled with external objects, such as rug edge edging or laces hanging from unknotted shoes. A method of disentanglement of an autonomous exhaustive robot system (such as Robot 100) may involve placing the Robot 100 on the floor surface first, but only when the robot departs from the dock (eg, quite a bit). It should be considered to include (after the delay, but placed on the floor). The robot 100 autonomously moves forward across the floor surface while operating the cleaning heads 106a and 106b. Robot 100 continues to travel across the floor surface in a constant direction, performing floor work and / or floor cleaning uninterrupted, while increasing the measured motor current (eg, spikes or increases above a threshold, predetermined). The edge cleaning head motor 118 can be reverse biased in response to a sharp increase in the gradient of.

In some cases, the robot 100 can move forward before reverse biasing the rotation of the edge cleaning head 106a in response to a high cleaning head motor current (apart from forward movement control by movement behavior). .. Robot 100 may independently reverse the rotation of the edge cleaning head 106a in response to the increased edge cleaning head 106a motor current for a period of time. The time for the increased current can be specified, for example, in seconds. After reverse biasing the rotation of the edge cleaning head 106, the robot 100 can move in the opposite direction, change its direction of movement, and move in a new direction.

In certain combinations, the robot extends across the center of the robot, for example, in a direction crossing the robot work path or in a direction parallel to the main drive wheels, as well as the side of the robot (the body of the robot). An edge cleaning head arranged on the side of the robot is also provided at a position where the edge cleaning head is extended beyond the circumference of the robot in the lateral direction so as to clean (not only directly under the robot). The main cleaning head 106b includes at least one rotary drive brush 111, and the edge cleaning head 106a includes at least one rotary drive brush 120.

As shown in FIG. 9C, the main cleaning head 106b is controlled, for example, by the brush motor control process 930. The brush motor control process monitors the current sensor of the main cleaning head motor and when a sudden current rise (eg, a threshold, a spike or rise that exceeds a predetermined amount of integrated or otherwise determined gradient) occurs. Optionally check if the robot is moving forward (eg, by monitoring the process, forward movement signs, or directly the main drive motor). If the robot 100 is moving forward and does not interrupt such forward movement (when the robot movement is controlled by a separate drive controlled by the action, it is optional from its ability to make such forward movement. The brush motor control process 930 applies a reverse bias to the brush motor.

The reverse bias does not cause the motor to spin in the opposite direction so as to avoid wrapping the same entwined cord, string, or bunch of ornaments in the opposite direction around the brush. Instead, the brush motor control process 930 applies a slight bias sufficient to keep the brush rotation almost neutral. As the robot 100 moves forward, a cord, string, or tuft that pulls the brush to unwind the entanglement only transfers attenuated torque in the opposite direction to the motor (eg, between the motor and the brush). Combined with reverse bias, this damped torque is when more tension is applied by the cord or string (because the gearbox allows reverse drive of the gearbox at the opposite mechanical magnification). For example, as the robot moves further away from where the cord or string or garment is attached, it results in an assisted but slowly increasing speed of rewinding of the entangled brush.

The reverse bias continues until the time runs out, or until the pulling or locking load is no longer detected by the motor (eg, no entanglement), at which point the process ends and the cleaning head is in the direction of cleaning the surface. Resume normal rotation.

The edge cleaning brush 120 of the edge cleaning head 106a receives substantially the same control in the edge brush motor control process 960, in which the rotation of the edge brush 120 is reverse biased in a similar manner. 962 (also shown in Figure 9B).

Thus, both the main brush 106b and the edge brush 106a are controlled separately from each other and separately from the robotic movement, allowing each to escape the entanglement without monitoring or interfering with the other. In some cases, each is entangled at the same time, separate but controlled at the same time, allowing both to be rewound or self-released at the same time. In addition, by placing the brush motor under reactive control (without waiting for the drive motor state or other overall robot state) and with only a slight reverse bias, the brush can detect any sudden current rise. As soon as the entanglement is grasped, it can be used for rewinding immediately, but in any case, it is not reversed to a sufficient amount to cause the same entanglement problem in the opposite direction.

In some cases, the motion control is separate from the brush state and does not monitor it, so the robot 100 keeps moving forward and the cleaning head 106b is after the robot 100 has moved forward by some amount. Then, the rotation of the main cleaning head 111 starts to be reverse biased. In some cases, the robot 100 can begin reversing the rotation of the main cleaning head 111 in response to a high cleaning head motor current for a period of time. After reversing the rotation of the main cleaning head 111, the robot 100 can move in the opposite direction, change the driving direction, and move in the driving direction.

FIGS. 17A to 17H show an example of a method of disentanglement of a comprehensive robot having various configurations of a cleaning head. Generally, the cleaning head has rollers that can be driven by an electric motor. Dirt and debris are picked up by the cleaning head and deposited in the container for later manual or automatic disposal. An electronic control device can also be provided for controlling the drive motor and the stirring brush roller for changing the direction of the exhaustive robot. In such a method, even after the exhaustive robot encounters an entangled situation, the exhaustive robot can resume cleaning in the absence of an operator.

FIG. 17A shows a side view of the cleaning head 201 of the exhaustive robot 200 in which the stirring roller 202 is in direct contact with the work surface. The roller 202 sweeps dirt 203 toward the suction duct 204 incorporated inside the brush chamber 206. By utilizing the air suction stream, the collected debris 210 can be transported to the container 212.

The cleaning head 201 can be stopped if the movement of the roller 202 is blocked or impeded to a predetermined or configurable degree, and the robot 200 has minimal power sufficient to cause the roller 202 to clear the obstacle. Is received in the opposite direction, and the direction can be reversed. For example, if the cord is wound around the roller 202, the roller 202 will be detached and rotatable so that the cord will rewind when the robot 200 retracts. Next, the robot 200 resumes the operation of the roller 202 in the original rotation direction, and resumes the operation of the robot in the original direction.

FIG. 17B shows another embodiment in which the robot 200 to which the brush roller 214 is added is used to release the entanglement. The brush roller 214 is driven by the same or different motors and can rotate perpendicular to the work surface. The brush roller 214 sends dirt 216 from the edge of the robot 200 to the dust collection area 218 of the roller 202.

In this embodiment, the cleaning head 201 can be stopped when the rollers 202 or 212 are blocked or disturbed to a predetermined or configurable degree, and the robot 200 is such that the rollers 202, 212 release the obstacle. It is possible to reverse the direction while receiving a sufficient minimum power in the opposite direction. For example, if the cord is wound around the roller 202 or 212, the roller 202 or 212 or both will be detached and rotatable so that the cord will rewind as the robot 200 retracts. Next, the robot 200 resumes the operation of the rollers 202 and 212 in the original rotation direction, and resumes the operation of the robot in the original direction.

FIG. 17C shows a bottom view of the exhaustive robot 240 and a side view of the cleaning head 246 inside the robot. The first brush roller 244 and the second brush roller 246 are in direct contact with the working surface. The rollers 244 and 246 agitate the working surface and dynamically lift the debris 248 trapped between these rollers towards the suction duct 250 incorporated inside the brush chamber 252. By utilizing the air suction stream 254, the collected debris 256 can be transported to the container 258.

The rollers 202, 212 can be stopped if the movements of the rollers 244, 246 are blocked or impeded to a predetermined or configurable extent, and the robot 240 is sufficient for the rollers 202, 212 to clear the obstacle. With the minimum amount of power received in the opposite direction, it is possible to move forward as indicated by the arrow 260 and resume the operation of the roller motor in the original direction of rotation.

FIG. 17D shows a robot 240 that executes another embodiment of the entanglement disengagement method. The rollers 244, 246 can be disconnected (ie, not actively driven) if the movement of the stirring rollers 244, 246 is blocked or impeded to a predetermined or configurable degree. The robot 240 then reverses direction as indicated by arrow 262, with the rollers 244 and 246 receiving minimal power in the opposite direction sufficient to clear the obstacle, at which point the rollers The 244 and 246 can be re-engaged in their original direction of rotation, and the robot 240 resumes operation in that original direction (indicated by arrow 264).

FIG. 17E shows a side view of the exhaustive robot 270 with three rollers. Robot 270 has a cleaning head 272 and side brushes 274. The cleaning head 272 has a vertical stirring roller 276 and a reverse rotating stirring roller 278. The stirring rollers 276 and 278 can be rotationally driven relative to each other and parallel to the working surface, and the brush rollers 274 are perpendicular to the working surface by one or more electric motors (not shown). It can be driven. The brush roller 274 pre-sweeps the working surface and pushes dirt and debris towards the stirring rollers 276, 278, as indicated by arrow 279. The stirring rollers 276 and 278 can push dirt 280 toward the suction duct 282 incorporated inside the brush chamber 284. By utilizing the air suction stream, the collected debris 288 can be transported to the container 290.

If the movement of the stirring rollers 276, 278 is blocked or impeded to a predetermined or configurable degree, one or more roller motors are stopped or in the opposite direction in an attempt to remove the obstacle or obstruction. Can be temporarily driven to. These one or more roller motors can then resume operation in the original direction of rotation.

FIG. 17F shows another embodiment of the method of disentanglement of the exhaustive robot 270. One or more roller motors may be stopped or temporarily driven in the opposite direction if the movement of the stirring rollers 276, 278 is blocked or impeded to a predetermined or configurable degree. These one or more roller motors can then resume driving the rollers 276, 278 in their original direction of rotation, while at the same time reversing the direction of movement of the robot 270 or its axis. Gives a twisting motion around. The robot 270 can then resume operation in its original direction.

FIG. 17G shows a side view and a bottom view of the exhaustive robot 300 equipped with two rollers and two air ducts. The robot 300 has a cleaning head 302, a vertical stirring roller 304, and a counter-rotating stirring roller 306. The stirring rollers 304 and 306 can be rotationally driven by one or more electric motors (not shown) to each other and parallel to the working surface.

The rollers 304 and 306 dynamically lift and push dirt and debris 307 toward the main air duct 308 incorporated inside the brush chamber 312. Dirt and debris delivered by rollers 304, 306 can encounter secondary air ducts 310 located behind the rollers. A suction stream generated by an air suction motor (not shown) can transport collected dirt and debris to container 314 via ducts 308, 210. A related electronic control device controls to drive a motor that turns and turns the robot 300 and also directs the stirring rollers 304, 306.

If the movement of the stirring rollers 304, 306 is blocked or obstructed, the controller is one of stopping one or more roller motors or giving the motors minimal power in the opposite direction. Or execute a plurality of operations, and then restart the operation of the roller motor in the original rotation direction. At the same time, the robot 300 can at least temporarily reverse its direction or give a twisting motion around its axis and then resume its motion in its original direction.

FIG. 17H shows another embodiment of the method of releasing the entanglement related to the robot 300 to which the brush roller 316 is added. The brush roller 316 has a vertical axis of rotation and can be driven by current or dedicated electric motors. The brush motor 316 pre-sweeps the work surface and pushes dirt and debris 318 toward the stirring rollers 304, 306 (indicated by arrows 318). Dirt and debris can then be removed as described above.

If the movement of the agitating rollers 304, 306 is blocked or obstructed, the controller stops one or more roller motors or gives the motors minimal power in the opposite direction and then back. The operation of the roller motor can be restarted in the direction of rotation. At the same time, the robot 300 can at least temporarily reverse its direction or give a twisting motion around its axis and then resume its motion in its original direction.

Other robot details and feature structures that can be combined with those described herein are the following US patent applications filed simultaneously with this application, namely the "AUTONOMOUS CONVERAGE ROBOT" with the assigned application number _____. It can be found in applications entitled "NAVIGATION SYSTEM", "MODULAR ROBOT" with the assigned application number _____, and "ROBOT SYSTEM" with the assigned application number _____. The entire content can be used for additional references.

Several embodiments have been described. However, it will be understood that various modifications can be implemented without departing from the spirit and scope of the claims below. Therefore, other embodiments are within the scope of the following claims.

<figref num="1">FIG. 1 shows an upward perspective view of an embodiment of an autonomous coverage robot.</figref><figref num="2">FIG. 2 shows a downward perspective view of an embodiment of the autonomous coverage robot.</figref><figref num="3">FIG. 3 shows an exploded view of an embodiment of the autonomous coverage robot.</figref><figref num="4">FIG. 4 shows a front perspective view of an embodiment of a main cleaning head that can be incorporated into an autonomous coverage robot.</figref><figref num="5">FIG. 5 shows an exploded view of an embodiment of a main cleaning head that can be used in an autonomous coverage robot.</figref><figref num="6A">FIG. 6A shows an upper perspective view of an embodiment of an edge cleaning head using a rotatable brush.</figref><figref num="6B">FIG. 6B shows an exploded view of an embodiment of the edge cleaning head.</figref><figref num="6C">FIG. 6C shows a schematic view of the inclination of the example of the edge cleaning head.</figref><figref num="7">FIG. 7 shows an embodiment of an edge cleaning head with a rotatable drainer.</figref><figref num="8A">Figure 8A shows a bumper that can be used in an autonomous coverage robot.</figref><figref num="8B">FIG. 8B shows the motion collision sensor and the proximity sensor.</figref><figref num="9A">FIG. 9A shows a block diagram of an exemplary robot, and FIGS. 9B and 9C show a flow diagram illustrating motion control and brush operation.</figref><figref num="9B">FIG. 9A shows a block diagram of an exemplary robot, and FIGS. 9B and 9C show a flow diagram illustrating motion control and brush operation.</figref><figref num="9C">FIG. 9A shows a block diagram of an exemplary robot, and FIGS. 9B and 9C show a flow diagram illustrating motion control and brush operation.</figref><figref num="10">FIG. 10 shows floor proximity sensors and mounting fasteners that can be used to detect adjacent floors.</figref><figref num="11">11 and 12 show a side view and an exploded view of the floor proximity sensor.</figref><figref num="12">11 and 12 show a side view and an exploded view of the floor proximity sensor.</figref><figref num="13">FIG. 13 shows an exploded view of the lid used in the floor proximity sensors shown in FIGS. 11 and 12.</figref><figref num="14">FIG. 14 is an exploded view showing an embodiment of the leg ring assembly.</figref><figref num="15">FIG. 15 is an exploded assembly view showing an embodiment of the derailment sensor.</figref><figref num="16">FIG. 16 is a cross-sectional view showing an embodiment of a leg ring assembly.</figref><figref num="17">FIGS. 17A to 17H illustrate examples of a method of disentanglement of coverage robots having various configurations of cleaning heads. FIG. 17A illustrates a method of disentanglement that can be used in a coverage robot with a stirring roller. FIG. 17B illustrates a method of disentanglement that can be used in coverage robots with stirring rollers and brush rollers. FIG. 17C has a side view and a bottom view illustrating a method of disentanglement of a coverage robot equipped with a double stirring roller. FIG. 17D illustrates another method of disentanglement with respect to the robot shown in FIG. 17C. FIG. 17E illustrates a method of disentanglement of a coverage robot with two stirring rollers and one brush roller. FIG. 17F illustrates another method of disentanglement of the coverage robot. FIG. 17G includes side and bottom views illustrating how to disentangle the coverage robot 300 with two stirring rollers and two air ducts. FIG. 17H includes side and bottom views illustrating how to disentangle the coverage robot 300 with two stirring rollers, one brush roller, and two air ducts.</figref>