System for localization and obstacle detection using a common receiver

• US 9,310,806 B2
• Filed: 01/05/2011
• Issued: 04/12/2016
• Est. Priority Date: 01/06/2010
• Status: Active Grant

• Current Assignee: iRobot Corporation
• Original Assignee: iRobot Corporation
• Inventors: Romanov, Nikolai, Case, James Philip, Dooley, Michael
• Primary Examiner(s): Holwerda, Stephen
• Application Number:
  US12/985,194
• Publication Number:
  US 20110166707A1
• Time in Patent Office: 1,924 Days
• Field of Search: 318/568.16, 700/258
• US Class Current: 1/1
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves
• CPC Class Codes: G05D 1/0242 using non-visible light signals, e.g. IR or UV signals

Abstract

A localization and obstacle detection system includes a first signal projector configured to project a first signal into an environment and a robot configured to move in the environment. The robot includes a second signal projector configured to project a second signal into the environment; a signal receiver configured to receive the first signal and the second signal; a localizer configured to determine a location of the robot in the environment based at least in part on the received first signal; and a detector configured to determine the presence of an obstacle in the environment based at least in part on the intensity and bearing of the received second signal and without touching the obstacle; wherein the second signal is distinct from the first signal in at least one characteristic.

Claims

1. A localization and obstacle detection system comprising:

a first signal projector configured to project a first signal into an environment; and

a robot comprising;

a second signal projector configured to project a second signal into the environment;

a first signal receiver configured to receive both the first signal and the second signal, wherein the first signal receiver comprises a single signal sensor used to receive both the first signal, used to determine a location of the robot, and the second signal, used to determine a presence of an obstacle;

a localizer configured to determine a location of the robot in the environment based at least in part on the first signal received by the single signal sensor; and

a detector configured to determine the presence of an obstacle in the environment based at least in part on the intensity and bearing of the second signal received by the single signal sensor and without touching the obstacle;

wherein the second signal is distinct from the first signal in at least one characteristic;

wherein the robot is configured to move in the environment.

2. The system of claim 1, wherein the first signal and the second signal are in the light spectrum, and wherein the single signal sensor comprises a first single light sensor, the first single light sensor used to sense both;

the first signal, used to determine a location of the robot, and

the second signal, used to determine a presence of an obstacle.

3. The system of claim 1, wherein the detector is configured to determine the presence of an obstacle based at least in part on the received second signal indicating that the robot is under an object, wherein the object comprises the obstacle and the received second signal, projected by the second signal projector, is reflected from a bottom side of the object.

4. The system of claim 1, wherein the detector is configured to determine the presence of an obstacle based at least in part on:

the received second signal indicating that the robot is under an object, wherein the object comprises the obstacle, such that;

a first incident angle determined by the second signal as detected by the first signal receiver at a first time;

is above a first threshold, or

exceeds by a second threshold a second measured incident angle determined by the second signal as detected by the first signal receiver at a second time prior to the first time.

5. The system of claim 1, wherein the detector is configured to determine the presence of an obstacle based at least in part on the received second signal indicating that the robot is approaching the obstacle.

6. The system of claim 1, wherein:

the detector is configured to determine the presence of an obstacle based at least in part on the received second signal indicating that the robot is approaching the obstacle; and

the second signal projector is configured to project the second signal substantially in a direction in which the robot is configured to move when in operation on a surface.

7. The system of claim 1, wherein:

the detector is configured to determine the presence of an obstacle based at least in part on the received second signal indicating that the robot is approaching the obstacle; and

,

the second signal projector is configured to project the second signal in a direction which is substantially orthogonal to a direction of movement of the robot in the environment.

8. The system of claim 1, wherein the detector is configured to determine the presence of an obstacle based at least in part on the received second signal indicating that the robot is approaching the obstacle, and

wherein the second signal projector and the first signal receiver are relatively positioned so that the detector determines the presence of an obstacle based at least in part on the analysis of reflections of the projected second signal received by the receiver,

said reflections having been reflected at least twice within the environment after being projected and before being received by the receiver.

9. The system of claim 1, wherein the detector is configured to determine the presence of an obstacle based at least in part on the received second signal indicating that the robot is approaching the obstacle, and

wherein the second signal projector and the first signal receiver are relatively positioned so that the detector determines the presence of an obstacle in the environment based at least in part on the analysis of direct reflections by the obstacle of the projected second signal received by the receiver.

10. The system of claim 1, wherein the detector is configured to determine the presence of an obstacle based at least in part on the received second signal indicating that the robot is approaching the obstacle, and,

wherein the second signal projector and the first signal receiver are relatively positioned so that the detector determines the presence of an obstacle based at least in part on the analysis of direct reflections by an object in the environment above the robot of the projected second signal received by the receiver.

11. The system of claim 1, wherein

the detector is configured to determine the presence of an obstacle based at least in part on the received second signal indicating that the robot is approaching the obstacle;

the second signal projector is configured to project the second signal in a direction which is substantially orthogonal to a direction of movement of the robot in the environment; and

the second signal is collimated.

12. The system of claim 1, wherein the localizer is further configured to use obstacle detection information from the detector to determine the location of the mobile device.

13. The system of claim 1, wherein the detector is configured to determine a presence of an overhanging obstacle having the potential to impede movement of the robot.

14. The system of claim 1, wherein the robot is further configured to transmit a signal configured to activate or deactivate at least a portion of the first signal projector'"'"'s functionality.

15. The system of claim 1, wherein the robot is further configured to transmit a signal configured to change an operational status of the first signal projector.

16. A localization and obstacle detection method comprising:

receiving at a first receiver physically associated with a mobile object both a first signal, the first signal projected from a source other than the mobile object, and a second signal, the second signal projected from the mobile object, wherein the first receiver comprises a single sensor used to receive both the first signal, used to determine a location of the robot, and the second signal, used to determine a presence of an obstacle;

distinguishing the first received signal from the second received signal based on at least one signal characteristic that differs between the first received signal and the second received signal;

localizing the mobile object in an environment based at least in part on the first received signal received at the single sensor;

determining that the mobile object is proximate to an obstacle in the environment based at least in part on the second received signal received at the single sensor;

maintaining a space between the mobile object and the proximate obstacle in the environment,

wherein the first signal and the second signal are of the same signal type and have at least one different characteristic relative to each other.

17. The method of claim 16, wherein the first receiver consists essentially of one or more optical sensors configured to receive the same type of light signal, wherein the one or more optical sensors comprise a first single optical sensor, the first single optical sensor configured to sense both:

the first signal, used to determine a location of the robot, and

the second signal, used to determine a presence of an obstacle.

18. The method of claim 16 wherein the mobile object has a heading of movement in the environment,

the method further comprising modifying the heading based at least in part on the determined proximity of the mobile object to an obstacle in the environment detected using the first signal or the second signal, or both the first signal and the second signal.

19. The method of claim 16 wherein the mobile object has a velocity of movement in the environment,

and the method further comprising modifying the velocity based at least in part on the determined proximity of the mobile object to an obstacle in the environment.

20. The method of claim 16, the method further comprising:

emitting the first signal from a stationary signal source spaced apart from the mobile object; and

emitting the second signal from the mobile object.

21. The method of claim 16, wherein localizing is based at least in part on determining obstacle proximity.

22. The method of claim 16, wherein determining obstacle proximity is based at least in part on localizing.

23. The method of claim 16, the method further comprising determining a presence of an overhanging obstacle having the potential to impede movement of the mobile object.

24. The method of claim 16, the method further comprising transmitting from the mobile object a signal configured to activate or deactivate at least a portion of the projector not on the robot.

25. The method of claim 16, the method further comprising transmitting from the mobile object a signal configured to change an operational status of the projector not on the robot.

26. A mobile robot comprising:

a signal projector configured to project a first signal into an environment, the first signal being of a first signal type and having a first value for a signal property;

a first signal receiver configured to receive signals of the first signal type, including at least both the first signal and a second signal, the second signal projected from a projector not on the robot, wherein the first signal receiver comprises a single sensor used to receive both the first signal, used to determine a location of the robot, and the second signal, used to determine a presence of an obstacle;

wherein the second signal is of the first signal type and has a second value for the signal property, the second value different from the first value;

a localizer configured to determine a location of the robot in the environment based at least in part on the second signal received by the single sensor; and

a detector configured to determine the presence of an obstacle in the environment based at least in part on the first signal received by the single sensor;

wherein the robot is configured to move in the environment.

27. The mobile robot of claim 26, wherein the detector is configured to determine a presence of an overhanging obstacle having the potential to impede movement of the mobile robot.

28. The mobile robot of claim 26, wherein the mobile robot is further configured to transmit a signal configured to activate or deactivate at least a portion of the first signal projector'"'"'s functionality.

29. The mobile robot of claim 26, wherein the mobile robot is further configured to transmit a signal configured to change an operational status of the first signal projector.

30. The mobile robot of claim 26, wherein the single sensor comprises a single light sensor configured to sense both:

the first signal, used to determine a location of the robot, and

the second signal, used to determine a presence of an obstacle.