Sensors arrangement

• US 6,493,612 B1
• Filed: 06/18/2001
• Issued: 12/10/2002
• Est. Priority Date: 12/18/1998
• Status: Expired due to Term

• Current Assignee: Dyson Technology Limited (Beeswax Holdings UK Limited)
• Original Assignee: Dyson Limited (Beeswax Holdings UK Limited)
• Inventors: Bisset, David Lindsey, Clark, Alan Gerard
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): MANCHO, RONNIE M
• Application Number:
  US09/868,492
• Time in Patent Office: 540 Days
• Field of Search: 701/23.1, 701/22, 180/167, 180/168, 180/169, 180/280, 706/905, 318/580, 318/587, 318/568.16, 340/943, 340/435, 153/19, 153/23, 153/39, 153/401, 134/18, 134/21, 134/6
• US Class Current: 701/23
• CPC Class Codes: A47L 2201/04 Automatic control of the travelling movement; Automatic obstacle detection
• CPC Class Codes: A47L 5/28 Suction cleaners with handles and nozzles fixed on the casings, e.g. wheeled suction cleaners with steering handle A47L5/24 takes precedence
• CPC Class Codes: A47L 9/00 Details or accessories of suction cleaners, e.g. mechanical means for controlling the suction or for effecting pulsating action; Storing devices specially adapted to suction cleaners or parts thereof; Carrying-vehicles specially adapted for suction cleaners
• CPC Class Codes: G05D 1/0214 in accordance with safety or protection criteria, e.g. avoiding hazardous areas monitoring the location of vehicles within a certain area, e.g. forbidden or allowed areas, in traffic control systems for road vehicles G08G1/13
• CPC Class Codes: G05D 1/0231 using optical position detecting means position-fixing by using electromagnetic waves other than radio waves, e.g. optical position detecting means G01S5/16
• CPC Class Codes: G05D 1/0255 using acoustic signals, e.g. ultra-sonic singals sonar systems designed for anti-collision purposes G01S15/93
• CPC Class Codes: Y10S 706/905 Vehicle or aerospace

Abstract

An autonomous vehicle, such as a robotic cleaning device, includes wheels which support the vehicle and allow the vehicle to traverse a surface. Downward looking wheel sensors sense the presence of a surface in front of the wheels. Another sensor is provided at or near a leading edge of the vehicle for sensing the presence beneath the leading edge of the vehicle. The vehicle is arranged so that movement of the vehicle is possible if the leading edge sensor senses that there is no surface beneath the leading edge of the vehicle, provided that the wheel sensors indicate that there is a surface adjacent to the wheel. When the leading edge sensor senses that there is no surface beneath the leading edge of the vehicle, the vehicle performs an edge following routine.

Claims

1. An autonomous vehicle comprising wheels for supporting the vehicle and for allowing the vehicle to traverse a surface, downward looking wheel sensors for sensing whether there is a surface in front of the wheels, a further sensor at or near a leading edge of the vehicle for sensing whether there is a surface beneath the leading edge of the vehicle and a control apparatus for controlling movement of the vehicle, the control apparatus being arranged to permit movement of the vehicle when the leading edge sensor senses that there is no surface beneath the leading edge of the vehicle, provided that the wheel sensors indicate that there is a surface adjacent the wheel.

2. A vehicle according to claim 1 wherein the control apparatus is arranged so that, when the leading edge sensors senses the absence of a surface beneath the leading edge of the vehicle, the vehicle performs an edge following routine.

3. A vehicle according to claim 2 arranged so that, the edge following routine is repetitive and causes the vehicle to reverse and then move forward at an angle to the leading edge until the leading edge sensor again senses the absence of a surface beneath the leading edge of the vehicle.

4. A vehicle according to claim 2 provided with a further downward looking sensor for sensing the presence of a surface adjacent a side edge of the vehicle outside of the path of the wheel, and wherein the edge following routine uses an output from the side edge sensor to follow the edge of a surface.

5. A vehicle according to claim 4 wherein the side edge sensor is mounted on the vehicle within the path of the wheel and is angled diagonally downward and outwardly from the vehicle to sense the presence of a surface adjacent a side edge of the vehicle outside of the path of the wheel.

6. A vehicle according to claim 4 or 5 wherein the side edge sensor senses the presence of a surface adjacent a side edge of the vehicle outside of the path of the wheel and forward of the wheel, in a direction normal to a direction of movement of the vehicle.

7. A vehicle according to claim 4 wherein the further sensor is mounted on an underside of the vehicle.

8. A vehicle according to claim 1, wherein the control apparatus further comprises a second control path which is arranged to receive inputs from only the downward looking wheel sensors, the second control path being arranged to stop the vehicle when the downward looking wheel sensors sense the absence of a surface adjacent the wheel, and wherein the second control path is implemented entirely in hardware.

9. A vehicle according to claim 1 in the form of an autonomous cleaning device.

10. A vehicle according to claim 1 in the form of an autonomous vacuum cleaner.

11. A method of operating an autonomous vehicle with wheels for supporting the vehicle and for allowing the vehicle to traverse a surface and a control apparatus for controlling movement of the vehicle, comprising:

receiving information from downward looking wheel sensors which sense a presence of a surface in front of the wheel; and

controlling movement of the vehicle so as to permit movement of the vehicle when a leading edge sensor senses that there is no surface beneath a leading edge of the vehicle, provided that the downward looking wheel sensors indicate a presence of a surface adjacent the wheel.

12. Software for performing a method of controlling operation of an autonomous vehicle comprising wheels for supporting the vehicle and for allowing the vehicle to traverse a surface, and a control apparatus for controlling movement of the vehicle, the software causing the control apparatus to:

receive information from downward looking wheel sensors, which sense whether there is a surface in front of the wheel, and from a further sensor, which senses whether there is a surface beneath the leading edge of the vehicle; and

,

control movement of the vehicle so as to permit movement of the vehicle when the leading edge sensor senses that there is no surface beneath the leading edge of the vehicle, provided that the wheel sensors indicate that there is a surface adjacent the wheel.

13. Control apparatus for controlling operation of an autonomous vehicle comprising wheels for supporting the vehicle and for allowing the vehicle to traverse a surface, the control apparatus being arranged to:

receive information from downward looking wheel sensors, which sense whether there is a surface in front of the wheel, and from a further sensor, which senses the presence of a surface beneath the leading edge of the vehicle; and

control movement of the vehicle so as to permit movement of the vehicle when the leading edge sensor senses that there is no surface beneath the leading edge of the vehicle, provided that the wheel sensors indicate that there is a surface adjacent the wheel.