Autonomous machine

• US 20060161318A1
• Filed: 02/13/2004
• Published: 07/20/2006
• Est. Priority Date: 02/14/2003
• Status: Active Grant

• Current Assignee: Dyson Technology Limited (Beeswax Holdings UK Limited)
• Original Assignee: Dyson Technology Limited (Beeswax Holdings UK Limited)
• Inventors: Aldred, Michael David, Bommer, Alexander Philip
• Granted Patent: US 7,873,437 B2
• Time in Patent Office: Days
• US Class Current: 701/23
• CPC Class Codes: A61L 2202/16 Mobile applications, e.g. portable devices, trailers, devices mounted on vehicles
• CPC Class Codes: B60L 2200/40 Working vehicles
• CPC Class Codes: B60L 9/00 Electric propulsion with power supply external to the vehicle electric propulsion for monorail vehicles, suspension vehicles or rack railways B60L13/00; in combination with batteries or fuel cells within the vehicle B60L50/53
• CPC Class Codes: G05D 1/0219 ensuring the processing of the whole working surface
• CPC Class Codes: G05D 1/0227 using mechanical sensing means, e.g. for sensing treated area
• 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
• CPC Class Codes: G05D 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30

Abstract

A control system is provided for navigating an autonomous machine around a working area in a manner that causes the machine to traverse substantially all of the free surface of the working area. The control system is arranged to cause the machine to follow a boundary of the working area and to perform a plurality of movements, each movement comprising the machine travelling away from the boundary of the working area, at an angle to the boundary, and returning again to the boundary. The machine moves along the boundary of the working area between each movement and repeats the movements as the machine follows substantially the entire boundary of the working area.

Claims

1. An autonomous machine comprising a control system for navigating the autonomous machine around a working area in a manner that causes the machine to traverse substantially all of the free surface of the working area, the control system being configured to cause the machine to follow a boundary of the working area and to perform a plurality of movements, each movement comprising the machine travelling outwardly from the boundary of the working area, at an angle to the boundary, and returning again to the boundary, the machine moving along the boundary of the working area between each movement and repeating the movements as the machine follows substantially the entire boundary of the working area.

2. An autonomous machine according to claim 1, wherein the control system is configured so that, during a movement, the outward and return trips are along paths which are substantially the same.

3. An autonomous machine according to claim 2, wherein the control system is configured so that the machine is caused to reverse during the return trip.

4. An autonomous machine according to claim 1, wherein the control system is configured so that, during a movement, the outward and return trips are along paths which are adjacent to, or partially overlap, one another.

5. An autonomous machine according to claim 4, wherein the control system is configured so that the amount of overlap can be controlled by a user.

6. An autonomous machine according to claim 1, 4 or 5, wherein the control system is configured so that, during a movement, the outward trip is for a maximum predetermined distance.

7. An autonomous machine according to claim 1, 4 or 5, wherein the control system is configured so that the outward journey is for the shortest of the events of:

(a) reaching an obstacle and (b) travelling for a predetermined distance.

8. An autonomous machine according to claim 1, 4 or 5, wherein the control system is configured so that each movement is at an angle which is substantially perpendicular to that part of the boundary from which it commences.

9. An autonomous machine according to claim 1, 4 or 5, wherein the control system is configured so that each movement is at an angle which is substantially perpendicular to a baseline direction, the baseline direction ordinarily being aligned with the boundary, and wherein the baseline direction is changed when the angular difference between the current baseline direction and a direction of a subsequent portion of the boundary is greater than a predetermined amount.

10. An autonomous machine according to claim 1, 4 or 5, wherein the control system is configured so that the outward trip of a movement follows a path which is adjacent to, or partially overlapping with, the return trip of the previous movement.

11. An autonomous machine according to claim 1, 4 or 5, wherein the control system is configured so that to cause the machine to follow the boundary of the area until it returns to a starting point on the boundary.

13. An autonomous machine according to claim 1, further comprising a location marker to be positioned at a starting point and a detector for detecting the location marker, and wherein the control system is arranged to recognize the starting point by detecting the location marker.

14. An autonomous machine according to claim 13, wherein the machine is powered via a power cable and the location marker is positionable on the power cable.

15. An autonomous machine according to claim 13 or 14, wherein the location marker is magnetic and the detector on the machine is responsive to the magnetic location marker.

16. An autonomous machine according to claim 13, wherein the machine is powered by an external power supply and the machine stores a length of power cable for connecting the machine to the external supply.

17. An autonomous machine according to claim 16, wherein, during each movement, the machine is configured to dispense the power cable during an outward trip from the boundary and to rewind the power cable during a return trip.

18. An autonomous machine according to claim 16 or 17, wherein during the return trip the machine follows the cable which has been laid during the outward trip.

19. An autonomous machine according to claim 16 or 17, wherein during the return trip the machine navigates to the boundary using odometry information.

20. An autonomous machine according to claim 16 or 17, wherein the control system is configured to cause the machine to stop following the boundary of the working area if the machine has dispensed all of the power cable.

21. An autonomous machine according to claim 20, wherein, if all of the power cable has been dispensed from the machine and the machine has not yet completed the working area, the control system is configured to return to a starting position in the working area and to begin moving in the opposite direction around the boundary from the starting position.

22. An autonomous machine according to claim 21, wherein, when the machine moves around the boundary in the opposite direction from the starting position, the control system is configured to detect when it has travelled around the entire boundary.

23. An autonomous machine according to claim 22, wherein the control system builds a map of visited positions in the working area and recognizes that it has travelled around the entire boundary by using the map.

12. (canceled)

24. A method of operating an autonomous machine around a working area in a manner that causes the machine to traverse substantially all of the free surface of the working area, the method comprising causing the machine to follow a boundary of the working area and to perform a plurality of movements, each movement comprising the machine travelling away from the boundary of the working area, at an angle to the boundary, and returning again to the boundary, the machine moving along the boundary of the working area between each movement and repeating the movements as the machine follows substantially the entire boundary of the working area.

25. A storage medium encoded with executable instructions representing software for controlling the movement of an autonomous machine around a working area in a manner that causes the machine to traverse substantially all of the free surface of the working area, the software being arranged to cause the machine to follow a boundary of the working area and to perform a plurality of movements, each movement comprising the machine travelling away from the boundary of the working area, at an angle to the boundary, and retuning again to the boundary, the machine moving along the boundary of the working area between each movement and repeating the movements as the machine follows substantially the entire boundary of the working area.

26. (canceled)