Methods and systems for controlling operation of a laser device

• US 9,121,703 B1
• Filed: 06/13/2013
• Issued: 09/01/2015
• Est. Priority Date: 06/13/2013
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Urmson, Chris, Droz, Pierre-yves
• Primary Examiner(s): Ratcliffe, Luke
• Assistant Examiner(s): Abraham, Samantha K
• Application Number:
  US13/916,933
• Time in Patent Office: 810 Days
• Field of Search: 356/3.01, 356/3.09, 356/4.01, 356/4.07, 356/5.01, 356/5.09, 356/9, 356/625
• US Class Current: 1/1
• CPC Class Codes: G01C 3/08 Use of electric radiation detectors
• CPC Class Codes: G01S 17/04 Systems determining the presence of a target
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46
• CPC Class Codes: G01S 17/87 Combinations of systems using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/931 of land vehicles
• CPC Class Codes: G01S 7/484 Transmitters
• CPC Class Codes: G01S 7/497 Means for monitoring or calibrating

Abstract

Example methods and systems for controlling operation of a laser device are provided. A method may include receiving an output of a proximity sensor that is positioned adjacent to a laser device, and determining based on the output of the proximity sensor that an object is within a threshold distance to the laser device. The method may also include based on the laser device emitting laser pulses, providing, by a computing device, instructions to discontinue the emission of laser pulses by the laser device based on the object being within the threshold distance. The method may further include based on the laser device being inactive, providing, by the computing device, instructions to prevent the emission of laser pulses by the laser device based on the object being within the threshold distance.

Claims

1. A method comprising:

receiving an output of a proximity sensor that is positioned adjacent to a laser device, wherein the laser device is configured to emit laser pulses;

determining based on the output of the proximity sensor that one or more objects are within a threshold distance to the laser device;

receiving laser data collected from scans of an environment by the laser device, wherein the laser data includes a plurality of laser data points indicative of the one or more objects in the environment;

making a determination of whether the one or more objects are within the threshold distance to the laser device based on the laser data;

when the laser device is emitting laser pulses, providing, by a computing device, instructions to discontinue the emission of laser pulses by the laser device based on the output of the proximity sensor and the laser data both being indicative of the one or more objects being within the threshold distance to the laser device; and

when the laser device is inactive, providing, by the computing device, instructions to prevent the emission of laser pulses by the laser device based on the output of the proximity sensor being indicative of the one or more objects being within the threshold distance to the laser device.

2. The method of claim 1, further comprising:

determining that the one or more objects are within a second threshold distance to the laser device, wherein the second threshold distance is greater than the threshold distance; and

based on the laser device emitting laser pulses, providing instructions to emit laser pulses by spreading a laser beam on a wide aperture.

3. The method of claim 1, further comprising:

determining that the one or more objects are within a second threshold distance to the laser device, wherein the second threshold distance is greater than the threshold distance; and

based on the laser device emitting laser pulses, providing instructions to emit laser pulses using an optical power below a threshold level.

4. The method of claim 1, further comprising:

receiving laser data collected from scans of an environment by the laser device, wherein the laser data includes a plurality of laser data points indicative of the one or more objects in the environment;

determining that the one or more objects is within a second threshold distance to the laser device, wherein the second threshold distance is greater than the threshold distance; and

based on the laser device emitting laser pulses, providing instructions to discontinue the emission of laser pulses by the laser device based on the one or more objects being within the second threshold distance.

5. The method of claim 1, further comprising:

determining a position of the one or more objects relative to an output of the laser device; and

based on the position of the one or more objects, determining whether to provide the instructions to discontinue or prevent the emission of laser pulses by the laser device.

6. The method of claim 5, wherein the laser device is configured to emit laser pulses while rotating, and the method further comprises:

providing instructions to stop emission of laser pulses by the laser device when the laser device rotates to a direction of the position of the one or more objects.

7. The method of claim 5, wherein the laser device is configured to emit laser pulses while rotating, and the method further comprises:

providing instructions to cause the emission of laser pulses by the laser device to turn off when the laser device rotates to the position of the one or more objects and to turn on when the laser device rotates past the position of the one or more objects.

8. The method of claim 1, wherein the laser device is a light detection and ranging sensor (LIDAR) that is coupled to a vehicle, and the vehicle is configured to operate in an autonomous mode.

9. The method of claim 1, wherein the proximity sensor includes one or more sensors selected from the group consisting of an inductive sensor configured to sense a metallic object, a capacitive sensor configured to sense a dielectric object, and an optical sensor configured to sense an opaque object.

10. The method of claim 1, wherein the proximity sensor is configured to sense black body infrared radiation emitted by the one or more objects.

11. The method of claim 1, wherein the proximity sensor is configured to emit infrared light in a direction of emission of laser pulses by the laser device and to determine an amount of returned infrared light.

12. The method of claim 1, wherein the threshold distance is a distance under about 30 centimeters.

13. The method of claim 1, wherein the laser device is mounted on a roof of a vehicle, and the proximity sensor is mounted on the roof of the vehicle adjacent to the laser device, wherein the laser device and the proximity sensor are separate components.

14. A system comprising:

at least one processor; and

data storage comprising instructions, that when executed by the at least one processor, cause the system to perform functions comprising;

receiving an output of a proximity sensor that is positioned adjacent to a laser device, wherein the laser device is configured to emit laser pulses;

determining based on the output of the proximity sensor that one or more objects are within a threshold distance to the laser device;

receiving laser data collected from scans of an environment by the laser device, wherein the laser data includes a plurality of laser data points indicative of the one or more objects in the environment;

making a determination of whether the one or more objects are within the threshold distance to the laser device based on the laser data;

when the laser device is emitting laser pulses, providing instructions to discontinue the emission of laser pulses by the laser device based on the output of the proximity sensor and the laser data both being indicative of the one or more objects being within the threshold distance to the laser device; and

when the laser device is inactive, providing instructions to prevent the emission of laser pulses by the laser device based on the output of the proximity sensor being indicative of the one or more objects being within the threshold distance to the laser device.

15. The system of claim 14, wherein the functions further comprise:

determining that the one or more objects are within a second threshold distance to the laser device, wherein the second threshold distance is greater than the threshold distance; and

based on the laser device emitting laser pulses, providing instructions to emit laser pulses by spreading a laser beam on a wide aperture or using an optical power below a threshold level.

16. A non-transitory computer readable storage medium having stored therein instructions, that when executed by a computing device, cause the computing device to perform functions comprising:

receiving an output of a proximity sensor that is positioned adjacent to a laser device, wherein the laser device is configured to emit laser pulses;

determining based on the output of the proximity sensor that one or more objects are within a threshold distance to the laser device;

receiving laser data collected from scans of an environment by the laser device, wherein the laser data includes a plurality of laser data points indicative of the one or more objects in the environment;

making a determination of whether the one or more objects are within the threshold distance to the laser device based on the laser data;

when the laser device is emitting laser pulses, providing instructions to discontinue the emission of laser pulses by the laser device based on the output of the proximity sensor and the laser data both being indicative of the one or more objects being within the threshold distance to the laser device; and

when the laser device is inactive, providing instructions to prevent the emission of laser pulses by the laser device based on the output of the proximity sensor being indicative of the one or more objects being within the threshold distance to the laser device.

17. The non-transitory computer readable storage medium of claim 16, wherein the functions further comprise:

receiving laser data collected from scans of an environment by the laser device, wherein the laser data includes a plurality of laser data points indicative of the one or more objects in the environment;

determining that the one or more objects is within a second threshold distance to the laser device, wherein the second threshold distance is greater than the threshold distance; and

based on the laser device emitting laser pulses, providing instructions to discontinue the emission of laser pulses by the laser device based on the one or more objects being within the second threshold distance.

18. The non-transitory computer readable storage medium of claim 16, wherein the laser device is configured to emit laser pulses while rotating, and wherein the functions further comprise:

determining a position of the one or more objects relative to an output of the laser device; and

providing instructions to cause the emission of laser pulses by the laser device to turn off when the laser device rotates to the position of the one or more objects and to turn on when the laser device rotates past the position of the one or more objects.