Robotic vacuum cleaner with edge and object detection system

• US 7,801,645 B2
• Filed: 03/11/2004
• Issued: 09/21/2010
• Est. Priority Date: 03/14/2003
• Status: Expired due to Fees

• Current Assignee: Sharper Image Acquisition, LLC (ThreeSixty Group Ltd.)
• Original Assignee: Sharper Image Acquisition, LLC (ThreeSixty Group Ltd.)
• Inventors: Brenner, Patricia I., Parker, Andrew J., Taylor, Charles E., Lau, Shek Fai, Ng, Eric, Heninger, Andrew, Blair, Eric C.
• Primary Examiner(s): Black; Thomas G
• Assistant Examiner(s): Olsen; Lin B
• Application Number:
  US10/799,573
• Publication Number:
  US 20040220698A1
• Time in Patent Office: 2,385 Days
• Field of Search: 700/246
• US Class Current: 700/258
• CPC Class Codes: G01S 17/10 using transmission of interrupted, pulse-modulated waves determination of distance by phase measurements G01S17/32
• CPC Class Codes: G01S 17/931 of land vehicles
• CPC Class Codes: G05D 1/0242 using non-visible light signals, e.g. IR or UV signals

Abstract

A robot uses an infrared sensor including an infrared light source which produces pulses of infrared light. Optics focus reflections of the infrared light pulses from different portions of the environment of the robot to different detectors in a 2D array of detectors. The detectors produce an indication of the distance to the closest object in an associated portion of the environment. The robot can use the indications to determine features in the environment. The robot can be controlled to avoid these features.

Claims

1. A robot comprising:

a motion unit;

a two-dimensional (2D) array of detectors supported by the motion unit, each detector having a counter associated therewith, the 2D array operable to generate a frame of distance indications to one or more features in an environment in which the robot operates;

an infrared sensor including;

(a) an infrared light source configured to produce a plurality of modulated pulses of infrared light directed toward the environment of the robot; and

(b) at least one optic element configured to focus a plurality of reflections of the infrared light pulses from the environment of the robot to the 2D array of detectors, causing the detection of the 2D array of detectors, wherein the modulated pulses enable detection of low-energy diffuse reflections; and

at least one processor operatively coupled to the 2D array of detectors, the processor operable;

(a) to determine one or more features of the environment based at least in part on one or more frames of distance indications; and

(b) to control the motion unit of the robot to avoid the one or more detected features.

2. The robot of claim 1, wherein the distance indication is produced by the counter measuring a period of time to receive a reflected pulse.

3. The robot of claim 2, wherein the feature is indicated in an internal map of the environment.

4. The robot of claim 2, wherein the feature is a step.

5. The robot of claim 2, wherein the feature is an object in a room.

6. The robot of claim 1, wherein the distance indication is produced by measuring an energy of a reflected pulse up to a cutoff time.

7. The robot of claim 1, wherein the robot is a robot cleaner.

8. The robot of claim 1, wherein the processor is further operable to add the one or more determined features to an internal map of the environment.

9. The robot of claim 1, further comprising a memory device for storing the one or more distance indications.

10. A method for controlling a robot comprising:

producing a plurality of modulated pulses of infrared light directed toward an environment of the robot;

focusing with at least one optic element a plurality of reflections of the infrared light pulses from the environment of the robot to a two-dimensional (2D) array of detectors;

detecting by the 2D array of detectors the plurality of reflections of the infrared light pulses, wherein the modulated pulses enable detection of low-energy diffuse reflections;

generating a frame of distance indications to one or more features in the environment;

processing the generated one or more frames of distance indications to determine one or more features of the environment; and

controlling the motion of the robot to avoid the one or more features of the environment.

11. The method of claim 10, wherein the distance indication is produced by a counter measuring the time to receive a reflected pulse.

12. The method of claim 11, wherein the feature is indicated in an internal map of the environment.

13. The method of claim 11, wherein the feature is a step.

14. The method of claim 11, wherein the feature is an object in a room.

15. The method of claim 10, wherein the distance indication is produced by measuring the energy of a reflected pulse up to a cutoff time.

16. The method of claim 10, wherein the robot is a robot cleaner.

17. A robot comprising:

an infrared light source configured to produce a plurality of modulated pulses of infrared light directed toward an environment of the robot;

a two-dimensional (2D) array of detectors, each detector having a counter associated therewith, the 2D array operable;

(a) to detect a plurality of reflections of the infrared light pulses from the environment, including low-energy diffuse reflections; and

(b) to generate a frame of distance indications to one or more features of the environment;

at least one processor operatively coupled to the 2D array of detectors, the processor operable;

(a) to determine one or more features of the environment based at least in part on one or more frames of distance indications; and

(b) to control the motion of the robot to avoid the one or more detected features.

18. The robot of claim 17, wherein the distance indication is produced by the counter measuring a period of time to receive a reflected pulse.

19. The robot of claim 18, wherein the feature is indicated in an internal map of the environment.

20. The robot of claim 18, wherein the feature is a step.

21. The robot of claim 18, wherein the feature is an object in a room.

22. The robot of claim 17, wherein the distance indication is produced by measuring an energy of a reflected pulse up to a cutoff time.

23. The robot of claim 17, wherein the robot is a robot cleaner.

24. The robot of claim 17, wherein the processor is further operable to add the one or more determined features to an internal map of the environment.

25. The robot of claim 17, further comprising a memory device for storing the one or more distance indications.

26. A method for controlling a robot comprising:

transmitting a plurality of modulated pulses of infrared light toward an environment of the robot;

detecting by an infrared detector a plurality of low-energy diffuse reflections of the infrared light pulses indicating distances to one or more features of an environment;

processing one or more distance indications to determine one or more features of the environment;

adding the one or more determined features to an internal map of the environment; and

controlling the motion of the robot to avoid the one or more features of the environment.

27. The method of claim 26, wherein the distance indication is produced by measuring the time to receive a reflected pulse from one or more features of the environment.

28. The method of claim 26, wherein the distance indication is produced by measuring the energy of a reflected pulse from one or more features of the environment.

29. The method of claim 26, wherein one or more features are indicated in the internal map of the environment.

30. The method of claim 26, wherein the feature is a step.

31. The method of claim 26, wherein the feature is an object in a room.

32. The method claim 26, wherein the robot is a robot cleaner.