Autonomous machine

• US 7,873,437 B2
• Filed: 02/13/2004
• Issued: 01/18/2011
• Est. Priority Date: 02/14/2003
• Status: Expired due to Fees

• Current Assignee: Dyson Technology Limited (Beeswax Holdings UK Limited)
• Original Assignee: Dyson Technology Limited (Beeswax Holdings UK Limited)
• Inventors: Bommer, Alexander Philip, Aldred, Michael David
• Primary Examiner(s): Tran; Dalena
• Assistant Examiner(s): Amin; Bhavesh V
• Application Number:
  US10/543,758
• Publication Number:
  US 20060161318A1
• Time in Patent Office: 2,531 Days
• Field of Search: 701/23, 701/301, 340/435, 700/245, 700/250
• US Class Current: 700/253
• 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 configured to navigate the autonomous machine around an outer boundary of an enclosed working area while performing a plurality of spike movements so that the autonomous machine travels over substantially all of a free surface of the enclosed working area,

wherein each of the plurality of spike movements comprises,

an outward movement, away from the outer boundary of the enclosed working area,

an inward movement, toward the outer boundary of the enclosed working area, and

a sideways movement, substantially parallel to the outer boundary of the enclosed working area,

wherein the control system is further configured to navigate the autonomous machine such that;

sideways movements of the spike movements are performed around substantially all of the outer periphery of the outer boundary, and

when the autonomous machine, when travelling along a first portion of the outer boundary and performing spike movements relative to the first portion of the outer boundary, encounters a second portion of the outer boundary that is positioned at an angle, internal to the outer boundary, of approximately 90 degrees relative to the first portion of the outer boundary, the autonomous machine is configured to begin to travel along the second portion of the outer boundary performing spike movements relative to the second portion of the boundary and substantially perpendicular to the spike movements performed relative to the first portion of the outer boundary,

wherein when performing at least one of the spike movements relative to the second portion of the outer boundary, the autonomous machine is configured to travel over a portion of the free surface of the enclosed working area that the autonomous machine previously travelled over while performing a spike movement relative to the first portion of the outer boundary, and

wherein the control system is further configured to return the autonomous machine to substantially a same position at which the navigation began when the autonomous machine has travelled over substantially all of a free surface of the enclosed working area.

2. An autonomous machine according to claim 1, wherein the control system is configured so that, during a spike movement, the outward movement and inward movement 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 inward movement.

4. An autonomous machine according to claim 1, wherein the control system is configured so that, during a spike movement, the outward movement and inward movement 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 spike movement, the outward movement 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 movement 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 spike 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 spike movement is at an angle which is substantially perpendicular to a baseline direction, the baseline direction ordinarily being aligned with the outer 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 outer 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 movement of a spike movement follows a path which is adjacent to, or partially overlapping with, the return trip of the previous spike movement.

11. 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.

12. An autonomous machine according to claim 11, wherein the machine is powered via a power cable and the location marker is positionable on the power cable.

13. An autonomous machine according to claim 11 or 12, wherein the location marker is magnetic and the detector on the machine is responsive to the magnetic location marker.

14. An autonomous machine according to claim 11, 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.

15. An autonomous machine according to claim 14, wherein, during each spike movement, the machine is configured to dispense the power cable during the outward movement and to rewind the power cable during the inward movement.

16. An autonomous machine according to claim 14 or 15, wherein during the inward movement the machine follows the cable which has been laid during the outward movement.

17. An autonomous machine according to claim 14 or 15, wherein during the inward movement the machine navigates to the outer boundary using odometry information.

18. An autonomous machine according to claim 14 or 15, wherein the control system is configured to cause the machine to stop following the outer boundary of the working area if the machine has dispensed all of the power cable.

19. An autonomous machine according to claim 18, wherein, if all of the power cable has been dispensed from the machine and the machine has not yet traveled over substantially all of the free space of the enclosed working area, the control system is configured to return to a starting position in the enclosed working area and to begin moving in an opposite direction around the outer boundary from the starting position.

20. An autonomous machine according to claim 19, wherein, when the machine moves around the outer boundary in the opposite direction from the starting position, the control system is configured to detect when the autonomous machine has travelled around the entire outer boundary.

21. An autonomous machine according to claim 20, wherein the control system builds a map of visited positions in the enclosed working area and is configured to recognize when it has travelled around the entire outer boundary by using the map.

22. A method of operating an autonomous machine around an enclosed working area in a manner that causes the machine to traverse substantially all of the free surface of the enclosed working area, the method comprising:

causing the autonomous machine to navigate around an outer boundary of the enclosed working area while performing a plurality of spike movements,

wherein each of the plurality of spike movements comprises,

an outward movement, away from the outer boundary of the enclosed working area,

an inward movement, toward the outer boundary of the enclosed working area, and

a sideways movement, substantially parallel to the outer boundary of the enclosed working area,

further causing the autonomous machine to navigate such that;

sideways movements of the spike movements are performed around substantially all of the outer periphery of the outer boundary, and

when the autonomous machine, when travelling along a first portion of the outer boundary and performing spike movements relative to the first portion of the outer boundary, encounters a second portion of the outer boundary that is positioned at an angle, internal to the outer boundary, of approximately 90 degrees relative to the first portion of the outer boundary, the autonomous machine is configured to begin to travel along the second portion of the outer boundary performing spike movements relative to the second portion of the boundary and substantially perpendicular to the spike movements performed relative to the first portion of the outer boundary,

wherein when performing at least one of the spike movements relative to the second portion of the outer boundary, the autonomous machine is configured to travel over a portion of the free surface of the enclosed working area that the autonomous machine previously travelled over while performing a spike movement relative to the first portion of the outer boundary, and

wherein the autonomous machine is further caused to return to substantially a same position at which the navigation began once the autonomous machine has travelled over substantially all of a free surface of the enclosed working area.

23. A storage medium encoded with executable instructions representing software for controlling the movement of an autonomous machine around an enclosed working area in a manner that causes the autonomous machine to traverse substantially all of the free surface of the enclosed working area,

the software being arranged to cause the autonomous machine to navigate around an outer boundary of an enclosed working while performing a plurality of spike movements,

wherein each of the plurality of spike movements comprises,

an outward movement, away from the outer boundary of the enclosed working area,

an inward movement, toward the outer boundary of the enclosed working area, and

a sideways movement, substantially parallel to the outer boundary of the enclosed working area,

wherein the software is further arranged to cause the autonomous machine to navigate such that;

sideways movements of the spike movements are performed around substantially all of the outer periphery of the outer boundary, and

when the autonomous machine, when travelling along a first portion of the outer boundary and performing spike movements relative to the first portion of the outer boundary, encounters a second portion of the outer boundary that is positioned at an angle, internal to the outer boundary, of approximately 90 degrees relative to the first portion of the outer boundary, the autonomous machine is configured to begin to travel along the second portion of the outer boundary performing spike movements relative to the second portion of the boundary and substantially perpendicular to the spike movements performed relative to the first portion of the outer boundary,

wherein when performing at least one of the spike movements relative to the second portion of the outer boundary, software is further arranged to cause the autonomous machine to travel over a portion of the free surface of the enclosed working area that the autonomous machine previously travelled over while performing a spike movement relative to the first portion of the outer boundary, and

wherein the software is further arranged to cause the autonomous machine to return to substantially a same position at which the navigation began when the autonomous machine has travelled over substantially all of a free surface of the enclosed working area.