SYSTEM FOR LOCALIZATION AND OBSTACLE DETECTION USING A COMMON RECEIVER

• US 20110166707A1
• Filed: 01/05/2011
• Published: 07/07/2011
• Est. Priority Date: 01/06/2010
• Status: Active Grant

• Current Assignee: iRobot Corporation
• Original Assignee: Evolution Robotics Inc. (iRobot Corporation)
• Inventors: Case, James Philip, Dooley, Michael, Romanov, Nikolai
• Granted Patent: US 9,310,806 B2
• Time in Patent Office: Days
• US Class Current: 700/255
• 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
• CPC Class Codes: G05D 2201/0203 Cleaning or polishing vehicle

Abstract

A localization and obstacle detection system comprising a first signal projector configured to project a first signal into an environment and a robot configured to move in the environment. The robot comprises 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 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;

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.

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.

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 such that;

a first incident angle determined by the second signal as detected by the 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 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 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 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 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. A localization and obstacle detection method comprising:

receiving a first signal at a first receiver physically associated with a mobile object, the first signal projected from a source other than the mobile object;

receiving at the first receiver a second signal projected from the mobile object;

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;

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

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.

14. The method of claim 13, wherein the first receiver consists essentially of one or more optical sensors configured to receive the same type of light signal.

15. The method of claim 13 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.

16. The method of claim 13 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.

17. The method of claim 13, 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.

18. The method of claim 13, wherein localizing is based at least in part on determining obstacle proximity.

19. The method of claim 13, wherein determining obstacle proximity is based at least in part on localizing.

20. 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 signal receiver configured to receive signals of the first signal type, including at least the first signal and a second signal projected from a project not on the robot,

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 received second signal; and

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

wherein the robot is configured to move in the environment.