Navigational Control System for a Robotic Device

• US 20100049364A1
• Filed: 07/30/2009
• Published: 02/25/2010
• Est. Priority Date: 09/13/2002
• Status: Active Grant

• Current Assignee: iRobot Corporation
• Original Assignee: iRobot Corporation
• Inventors: Cohen, David A., Landry, Gregg W., Ozick, Daniel N., Chiappetta, Mark J., Jones, Joseph L.
• Granted Patent: US 8,386,081 B2
• Time in Patent Office: Days
• US Class Current: 700/245
• CPC Class Codes: G05D 1/0227 using mechanical sensing means, e.g. for sensing treated area
• CPC Class Codes: G05D 1/0242 using non-visible light signals, e.g. IR or UV signals
• CPC Class Codes: G05D 1/0272 comprising means for registering the travel distance, e.g. revolutions of wheels measuring distance traversed on the ground by vehicles, e.g. using odometers G01C22/00

Abstract

An autonomous cleaning apparatus includes a chassis, a drive system disposed on the chassis and operable to enable movement of the cleaning apparatus, and a controller in communication with the drive system. The controller includes a processor operable to control the drive system to steer movement of the cleaning apparatus. The autonomous cleaning apparatus includes a cleaning head system disposed on the chassis and a sensor system in communication with the controller. The sensor system includes a debris sensor for generating a debris signal, a bump sensor for generating a bump signal, and an obstacle following sensor disposed on a side of the autonomous cleaning apparatus for generating an obstacle signal. The processor executes a prioritized arbitration scheme to identify and implement one or more dominant behavioral modes based upon at least one signal received from the sensor system.

Claims

1. An autonomous cleaning apparatus comprising:

a chassis;

a drive system disposed on the chassis and operable to enable movement of the cleaning apparatus;

a controller in communication with the drive system, the controller including a processor operable to control the drive system to steer movement of the cleaning apparatus; and

a cleaning head system disposed on the chassis;

a sensor system in communication with the controller, the sensor system comprising;

a debris sensor for generating a debris signal;

a bump sensor for generating a bump signal; and

an obstacle following sensor disposed on a side of the autonomous cleaning apparatus for generating an obstacle signal;

wherein the processor executes a prioritized arbitration scheme to identify and implement one or more dominant behavioral modes based upon at least one signal received from the sensor system.

2. The autonomous cleaning apparatus of claim 1, wherein the processor implements a spot cleaning mode in an area in which the cleaning apparatus was operating, substantially immediately in response to receiving a debris signal generated by the debris sensor.

3. The autonomous cleaning apparatus of claim 1, wherein the spot cleaning mode comprises maneuvering the autonomous cleaning apparatus according to a self-bounded area algorithm.

4. The autonomous cleaning apparatus of claim 3, wherein the self-bounded area algorithm comprises a spiraling algorithm at a reduced drive speed.

5. The autonomous cleaning apparatus of claim 1, wherein the processor implements a high power cleaning mode in response to the debris signal, the high power mode comprising elevating power delivery to the cleaning head system.

6. The autonomous cleaning apparatus of claim 1, wherein the debris sensor comprises a piezoelectric sensor located proximate to a cleaning pathway and responsive to a debris impact thereon to generate a debris signal indicative of such impact.

7. The autonomous cleaning apparatus of claim 1, wherein the debris sensor comprises:

a plate;

an elastomer pad supporting the plate; and

a piezoelectric material and an electrode both secured to the plate, the electrode in communication with the controller.

8. The autonomous cleaning apparatus of claim 1, wherein the debris sensor comprises a piezoelectric film.

9. The autonomous cleaning apparatus of claim 1, wherein the sensor system comprises right and left debris sensors in communication with the controller and disposed proximate a cleaning pathway of the cleaning head system for generating respective debris signals;

and

wherein the processor directs the drive system to turn right in response to the debris signal generated by the right debris sensor and to turn left in response to the debris signal generated by the left debris sensor.

10. The autonomous cleaning apparatus of claim 9, wherein the right and left debris sensors are disposed opposite each other and equidistantly from a center axis defined by the cleaning pathway.

11. The autonomous cleaning apparatus of claim 1, wherein the bump sensor comprises a displaceable bumper attached to the chassis and at least one break-beam sensor disposed on the displaceable bumper, the break-beam sensor activated upon displacement of the bumper toward the chassis.

12. The autonomous cleaning apparatus of claim 1, wherein the obstacle following sensor comprises an emitter emitting an emission signal laterally and a detector configured to detect the emission reflected off an obstacle adjacent the cleaning apparatus, the emitter and detector configured to establish a focal point.

13. The autonomous cleaning apparatus of claim 1, wherein the obstacle following sensor is disposed on a dominant side of the autonomous cleaning apparatus.

14. The autonomous cleaning apparatus of claim 1, wherein the sensor system further comprises a cliff sensor for generating a cliff signal upon detection of a cliff.

15. The autonomous cleaning apparatus of claim 14, wherein the cliff sensor comprises an emitter emitting an emission signal downwardly and a detector configured to detect the emission reflected off a surface being traversed by the cleaning apparatus, the emitter and detector configured to establish a focal point below the cleaning apparatus.

16. The autonomous cleaning apparatus of claim 1, wherein the sensor system further comprises a wheel drop sensor.

17. The autonomous cleaning apparatus of claim 1, wherein the sensor system further comprises a stall sensor.

18. An autonomous cleaning apparatus comprising:

a chassis;

a drive system disposed on the chassis and operable to enable movement of the cleaning apparatus;

a controller in communication with the drive system, the controller including a processor operable to control the drive system to steer movement of the cleaning apparatus; and

a cleaning head system disposed on the chassis;

a sensor system in communication with the controller, the sensor system comprising;

a debris sensor for generating a debris signal;

a bump sensor for generating a bump signal; and

an obstacle following sensor disposed on a side of the autonomous cleaning apparatus for generating an obstacle signal;

wherein the processor executes a prioritized arbitration scheme to identify and implement one or more dominant behavioral modes based upon at least one signal received from the sensor system;

wherein the processor controls one or more operational conditions of the autonomous cleaning apparatus based upon the debris signal; and

wherein the processor controls the drive system to execute a pattern of movements to steer the autonomous cleaning apparatus toward a debris area corresponding to the debris signal generated by the debris sensor.

19. An autonomous cleaning apparatus comprising:

a drive system operable to enable movement of the cleaning apparatus;

a controller in communication with the drive system, the controller including a processor operable to control the drive system to provide at least one pattern of movement of the cleaning apparatus; and

a debris sensor for generating a debris signal indicating that the cleaning apparatus has encountered debris, the debris sensor located along a cleaning passageway of the cleaning apparatus and responsive to debris passing through the cleaning passageway to generate a signal indicative of such passing;

wherein the processor is responsive to the debris signal to select a pattern of movement of the cleaning apparatus; and

wherein the pattern of movement comprises steering the cleaning apparatus toward an area containing debris.

20. The autonomous cleaning apparatus of claim 19, wherein the pattern of movement comprises spot coverage of an area containing debris.