Obstruction management system for robots

• US 6,810,305 B2
• Filed: 02/16/2001
• Issued: 10/26/2004
• Est. Priority Date: 02/16/2001
• Status: Expired due to Fees

• Current Assignee: The Procter & Gamble Company
• Original Assignee: The Procter & Gamble Company
• Inventors: Kirkpatrick, James Frederick Jr.
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Marc, McDieunel, Marc, McDieunel
• Application Number:
  US09/785,357
• Publication Number:
  US 20020116089A1
• Time in Patent Office: 1,348 Days
• Field of Search: 700/245, 318/587, 318/568.12, 318/581, 701/23, 701/24, 701/25, 180/167, 180/169, 180/6.5, 340/988
• US Class Current: 700/245
• CPC Class Codes: A47L 2201/04 Automatic control of the travelling movement; Automatic obstacle detection
• CPC Class Codes: A47L 9/009 Carrying-vehicles; Arrangements of trollies or wheels; Means for avoiding mechanical obstacles
• 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 1/0255 using acoustic signals, e.g. ultra-sonic singals sonar systems designed for anti-collision purposes G01S15/93

Abstract

A system for mobile robots to detect obstructions. Obstructions include objects which may impair the or impede the mobility of the robot, as well as transitions from carpeted surfaces to hard surfaces, transitions from hard surfaces to carpet, or transitions between other types of flooring. The system includes a plow which may move underneath the obstruction, The obstruction may the be brushed aside, or rise to an elevation detectable by the robot. Upon detection, the robot may change its direction of movement or stop moving altogether.

Claims

1. A mobile robot, the robot comprising a chassis and a plow flexibly attached to the chassis;

an annular clearance being provided between the plow and the chassis;

a sensor to detect changes in said clearance resulting from collisions between obstructions and the plow.

2. A robot according to claim 1 wherein said robot changes direction in response to detecting a change in said clearance.

3. The robot of claim 2 wherein the plow is vertically adjustable on the robot.

4. A robot according to claim 1 wherein the surface transition detection system comprises an attachment rod inserted in a channel, the channel is provided with a spring-loaded contact switch to detect displacement of said rod.

5. A robot according to claim 4 wherein said rod is substantially horizontal while robot is in motion.

6. A mobile robot having a surface transition detection system, the robot comprising a chassis and a plow flexibly attached to the chassis;

an annular clearance being provided between the plow and the chassis;

a sensor to detect changes in said clearance resulting from collisions between obstructions and the plow, said robot having at least one floor contacting element wherein the surface transition detection system comprises a vibration sensor mounted on a surface contacting element of the robot.

7. A mobile robot having a surface transition detection system, the robot comprising a chassis and a plow flexibly attached to the chassis;

an annular clearance being provided between the plow and the chassis;

a sensor to detect changes in said clearance resulting from collisions between obstructions and the plow, said robot having a shell pivotally mounted on said chassis.

8. A surface transition detection system for a mobile robot, said system comprising a plow and acoustic and/or optical sensors positioned above the plow to detect material lifted in front of the sensor by the plow while the robot is in motion.

9. An obstruction management system for a mobile robot having a periphery and a leading face and being disposable on a support surface, said system comprising a plow juxtaposed with said leading face and extending outwardly from the periphery of said robot, said plow being disposed in acute angular relationship relative to said support surface.

10. A system according to claim 9 wherein said plow has a clearance from said support surface of less than 10 mm.

11. A system according to claim 9 further comprising a sensor disposed at an elevation above said plow, said sensor detecting obstructions intercepted by said plow and lifted to said elevation.

12. A system according to claim 9 wherein said plow has a forward face, said forward face forming an angle of 30 to 60 degrees relative to said support surface.

13. A system according to claim 9 wherein said plow has chevron shape with a vertex.

14. A system according to claim 9 wherein said plow subtends an angle of at least 90 degrees.

15. A system according to claim 14 wherein said plow subtends an angle of 360 degrees.

16. A system according to claim 15 wherein said plow is concave.