Vehicle camera alignment

• US 10,848,744 B2
• Filed: 02/27/2019
• Issued: 11/24/2020
• Est. Priority Date: 02/27/2019
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Petniunas, Alexander, Brautigan, Patrick, Krishnan, Venkatesh
• Primary Examiner(s): Ye, Lin
• Assistant Examiner(s): Yoder, III, Chriss S
• Application Number:
  US16/287,138
• Publication Number:
  US 20200275033A1
• Time in Patent Office: 636 Days
• CPC Class Codes: G02B 6/4226 Positioning means for moving the elements into alignment, e.g. alignment screws, deformation of the mount
• CPC Class Codes: G02B 6/4227 Active alignment methods, e.g. procedures and algorithms
• CPC Class Codes: G06T 7/521 from laser ranging, e.g. using interferometry; from the projection of structured light
• CPC Class Codes: G06T 7/80 Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration
• CPC Class Codes: H04N 13/139 Format conversion, e.g. of frame-rate or size
• CPC Class Codes: H04N 13/204 using stereoscopic image cameras stereoscopic photography G03B35/00
• CPC Class Codes: H04N 13/239 using two 2D image sensors having a relative position equal to or related to the interocular distance H04N13/243 takes precedence
• CPC Class Codes: H04N 13/246 Calibration of cameras
• CPC Class Codes: H04N 23/675 comprising setting of focusing regions

Abstract

A system includes two stereo cameras mounted on a vehicle, at least one sensor arranged to detect a relative alignment of the stereo cameras, and a computer communicatively coupled to the stereo cameras and the at least one sensor. The computer is programmed to continuously apply a compensating adjustment to one of the stereo cameras based on the relative alignment.

Claims

1. A system comprising:

two stereo cameras mounted on a vehicle;

at least one sensor arranged to detect a relative alignment of the stereo cameras; and

a computer communicatively coupled to the stereo cameras and the at least one sensor;

wherein the at least one sensor includes a laser and a receptor each fixed relative to a first of the stereo cameras and a reflector fixed relative to a second of the stereo cameras;

wherein the reflector has at least three diffuse, nonplanar surfaces; and

the computer is programmed to;

determine the relative alignment based on data from the receptor, the data from the receptor including speckle patterns for each of the three surfaces, the relative alignment including tilts about three axes, each tilt determined by a respective one of the speckle patterns; and

continuously apply a compensating adjustment to one of the stereo cameras based on the relative alignment.

2. The system of claim 1, further comprising at least one actuator positioned to move the one of the stereo cameras in at least two dimensions, wherein applying a compensating adjustment to one of the two stereo cameras includes instructing the at least one actuator to move the one of the stereo cameras.

3. The system of claim 1, wherein the compensating adjustment is a pixel shift in two dimensions applied to visual data from the one of the stereo cameras.

4. The system of claim 1, wherein applying a compensating adjustment to one of the two stereo cameras includes discarding all visual data produced when the relative alignment is outside a threshold.

5. A computer comprising a processor and a memory storing instructions executable by the processor to:

continuously apply a compensating adjustment to one of two stereo cameras mounted on a vehicle based on a relative alignment of the stereo cameras;

wherein applying a compensating adjustment to one of the two stereo cameras includes discarding all visual data produced when the relative alignment is outside a threshold.

6. The computer of claim 5, wherein the instructions further include determining the relative alignment based on data from a receptor positioned to detect light generated by a laser fixed relative to one of the stereo cameras and reflected off a reflector fixed relative to the other of the stereo cameras.

7. The computer of claim 6, wherein the reflector has at least three diffuse, nonplanar surfaces, and wherein the data from the receptor includes speckle patterns for the three surfaces.

8. The computer of claim 6, wherein the laser and the receptor are included in one of at least three interferometers, and determining the relative alignment based on data from the receptor includes determining the relative alignment based on data from the interferometers.

9. The computer of claim 6, wherein the reflector includes a plurality of diffraction gratings each having a different orientation.

10. The computer of claim 6, wherein the laser and the receptor are included in one of at least three deflectometers, and determining the relative alignment based on data from the receptor includes determining the relative alignment based on data from the deflectometers.

11. The computer of claim 5, wherein the instructions further include determining the relative alignment based on data from two inertial measurement units each fixed relative to a respective one of the stereo cameras.

12. The computer of claim 5, wherein the instructions further include determining the relative alignment based on data from a sensor detecting light transmitted through a plurality of optical fibers extending along a rod elongated between two ends fixed relative to a respective one of the stereo cameras.

13. The computer of claim 5, wherein the relative alignment is represented at least in two rotational dimensions.

14. The computer of claim 13, wherein the relative alignment is outside the threshold when either of the two rotational dimensions is outside the threshold.

15. The computer of claim 13, wherein the relative alignment is outside the threshold when a sum of the two rotational dimensions is outside the threshold.

16. A method comprising:

continuously applying a compensating adjustment to one of two stereo cameras mounted on a vehicle based on a relative alignment of the stereo cameras;

wherein applying a compensating adjustment to one of the two stereo cameras includes discarding all visual data produced when the relative alignment is outside a threshold.

17. The method of claim 16, further comprising determining the relative alignment based on data from a receptor positioned to detect light generated by a laser fixed relative to one of the stereo cameras and reflected off a reflector fixed relative to the other of the stereo cameras.

18. The method of claim 17, wherein the reflector has at least three diffuse, nonplanar surfaces, and wherein the data from the receptor includes speckle patterns for the three surfaces.

19. The method of claim 17, wherein the laser and the receptor are included in one of at least three interferometers, and determining the relative alignment based on data from the receptor includes determining the relative alignment based on data from the interferometers.

20. The method of claim 17, wherein the reflector includes a plurality of diffraction gratings each having a different orientation.