Variable Beam Spacing, Timing, and Power for Vehicle Sensors

• US 20190033430A1
• Filed: 09/28/2018
• Published: 01/31/2019
• Est. Priority Date: 03/17/2017
• Status: Active Grant

• Current Assignee: Waymo LLC (Alphabet Inc.)
• Original Assignee: Waymo LLC (Alphabet Inc.)
• Inventors: Ingram, Benjamin, Droz, Pierre-Yves, Wachter, Luke, McCloskey, Scott, Gassend, Blaise, Pennecot, Gaetan
• Granted Patent: US 10,634,769 B2
• Time in Patent Office: Days
• 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: G01S 7/4815 using multiple transmitters
• CPC Class Codes: G01S 7/484 Transmitters
• CPC Class Codes: H01S 3/2308 Amplifier arrangements, e.g. MOPA
• CPC Class Codes: H01S 5/4025 Array arrangements, e.g. constituted by discrete laser diodes or laser bar H01S5/42 takes precedence
• CPC Class Codes: H01S 5/4056 emitting light in more than one direction

Abstract

The present disclosure relates to systems and methods that facilitate light detection and ranging operations. An example transmit block includes at least one substrate with a plurality of angled facets. The plurality of angled facets provides a corresponding plurality of elevation angles. A set of angle differences between adjacent elevation angles includes at least two different angle difference values. A plurality of light-emitter devices is configured to emit light into an environment along the plurality of elevation angles toward respective target locations so as to provide a desired resolution and/or a respective elevation angle. The present disclosure also relates to adjusting shot power and a shot schedule based on the desired resolution and/or a respective elevation angle.

Claims

1. A method comprising:

determining a respective beam elevation angle for each light-emitter device of a plurality of light-emitter devices, wherein respective light-emitter devices are coupled to respective die attach locations disposed along a front edge of at least one substrate, and wherein a set of angle differences between beam elevation angles of adjacent light-emitter devices comprises a non-uniform beam elevation angle distribution;

determining a desired shot schedule of the plurality of light-emitter devices based on the determined beam elevation angles; and

causing the plurality of light-emitter devices to emit light pulses into an environment according to the desired shot schedule.

2. The method of claim 1, wherein determining the respective beam elevation angle for each light-emitter device of the plurality of light-emitter devices is based on at least one of:

a location or an orientation of the light-emitter device on the at least one substrate.

3. The method of claim 1, wherein determining the desired shot schedule is further based on a comparison between the respective beam elevation angles and at least one value based on at least one of:

real-time point cloud data or historic point cloud data.

4. The method of claim 1, wherein the desired shot schedule comprises information indicative about which light-emitter device of the plurality of light-emitter devices is to be fired.

5. The method of claim 1, wherein the desired shot schedule comprises information indicative about how long a given light-emitter device of the plurality of light-emitter devices is to be fired.

6. The method of claim 1, wherein the desired shot schedule comprises information indicative about how long to wait before firing a given light-emitter device of the plurality of light-emitter devices.

7. The method of claim 1, further comprising determining a region of interest in the environment, wherein determining the desired shot schedule comprises adjusting, based on the region of interest, at least one of:

i) which light-emitter device of the plurality of light-emitter devices is to be fired;

ii) how long a given light-emitter device of the plurality of light-emitter devices is to be fired;

or

iii) how long to wait before firing a given light-emitter device of the plurality of light-emitter devices.

8. A method comprising:

determining, based on an emission angle, an anticipated target range of light pulses emitted from at least one light-emitter device;

determining a desired shot schedule of the at least one light-emitter device based on the determined anticipated target range; and

causing the at least one light-emitter device to emit light pulses into an environment according to the desired shot schedule.

9. The method of claim 8, wherein the at least one light-emitter device is coupled to a respective die attach location disposed along a front edge of at least one substrate, and wherein determining the anticipated target range of light pulses emitted from the at least one light-emitter device is based on at least one of:

a location or an orientation of the at least one light-emitter device on the at least one substrate.

10. The method of claim 8, wherein determining the desired shot schedule is further based on a comparison between the anticipated target range and at least one value based on at least one of:

real-time point cloud data or historic point cloud data.

11. The method of claim 8, wherein the at least one light-emitter device comprises a plurality of light-emitter devices, and wherein the desired shot schedule comprises information indicative about which light-emitter device of the plurality of light-emitter devices is to be fired.

12. The method of claim 8, wherein the desired shot schedule comprises information indicative about how long the at least one light-emitter device is to be fired.

13. The method of claim 8, wherein the desired shot schedule comprises information indicative about how long to wait before firing the at least one light-emitter device.

14. The method of claim 8, further comprising determining a region of interest in the environment, wherein determining the desired shot schedule comprises adjusting, based on the region of interest, at least one of:

i) which light-emitter device of a plurality of light-emitter devices is to be fired;

ii) how long a given light-emitter device of the plurality of light-emitter devices is to be fired;

or

iii) how long to wait before firing a given light-emitter device of the plurality of light-emitter devices.

15. The method of claim 8, further comprising determining the emission angle based on an angle of a spinning mirror interacting with light pulses emitted from the at least one light-emitter device.

16. A system comprising:

a plurality of light-emitter devices, wherein each light-emitter device is coupled to a respective die attach location and has a respective beam elevation angle, wherein the plurality of light-emitter devices is configured to emit light into an environment along the plurality of beam elevation angles toward respective target locations, and wherein a set of angle differences between beam elevation angles of adjacent light-emitter devices comprises at least two different angle difference values;

a plurality of pulser circuits, wherein the plurality of pulser circuits includes a respective pulser circuit for each light-emitter device in the plurality of light-emitter devices; and

a controller configured to control, for each given light-emitter device in the plurality of light-emitter devices, the respective pulser circuit for the given light-emitter device so as to emit light pulses according to a desired shot schedule, wherein the desired shot schedule is based on at least one of;

a beam elevation angle of light pulses emitted from the given light-emitter device or an anticipated target range of light pulses emitted from the given light-emitter device.

17. The system of claim 16, wherein at least one respective angle difference between adjacent beam elevation angles below a horizontal plane is greater than respective angle differences between adjacent beam elevation angles above the horizontal plane.

18. The system of claim 16, further comprising a spinning mirror configured to interact with the light pulses emitted from the plurality of light-emitter devices.

19. The system of claim 16, wherein the respective die attach locations comprise respective angled facets of a plurality of angled facets disposed along a front edge of at least one substrate.

20. The system of claim 16, wherein the plurality of light-emitter devices are components of a light detection and ranging system of a vehicle.