Path sensing using structured lighting

Patent metadata

Field	Value
Publication number	US-10083361-B2
Application number	US-201514852704-A
Country	US
Kind code	B2
Filing date	Sep 14, 2015
Priority date	Mar 15, 2013
Publication date	Sep 25, 2018
Grant date	Sep 25, 2018

Abstract

A structured light pattern is projected onto the path of a vehicle so as to generate a plurality of light spots, and an image thereof is captured from the vehicle. A world-space elevation of at least a portion of the light spots is responsive to a pitch angle of the vehicle determined responsive to image-space locations of down-range-separated light spots.

First claim

What is claimed is:

1. A method of sensing a physical feature of or along a path of a vehicle, comprising:
a. projecting a structured light pattern from a vehicle onto a path upon which said vehicle may travel, so as to generate a plurality of light spots on said path, wherein at least two of said plurality of light spots are at different world-space down-range locations relative to said vehicle;
b. capturing from said vehicle at least one image of said plurality of light spots using at least one camera;
c. determining at least two image-space locations in said at least one image of a corresponding said at least two of said plurality of lights spots at said different world space down-range locations;
d. determining a pitch angle of said vehicle responsive to said at least two of said plurality of light spots;
e. determining corresponding world-space elevations of at least a portion of said plurality of light spots responsive to said pitch angle of said vehicle; and
f. determining said pitch angle of said vehicle responsive to at least one image-space separation of at least one pair of said plurality of light spots.

2. A method of sensing a physical feature of or along a path of a vehicle, comprising:
projecting a structured light pattern from a vehicle onto a path upon which said vehicle may travel, so as to generate a plurality of light spots on said path, wherein at least two of said plurality of light spots are at different world-space down-range locations relative to said vehicle;
capturing from said vehicle at least one image of said plurality of light spots using at least one camera;
determining at least two image-space locations in said at least one image of a corresponding said at least two of said plurality of lights spots at said different world space down-range locations;
determining a pitch angle of said vehicle responsive to said at least two of said plurality of light spots; and
determining corresponding world-space elevations of at least a portion of said plurality of light spots responsive to said pitch angle of said vehicle; and
transforming said at least one image to a plurality of elevation tiles, wherein each elevation tile of said plurality of elevation tiles comprises a plurality of corners that are defined by corresponding image-space locations of associated light spots of said plurality of light spots, and a world-space elevation of each said elevation tile is determined as a median or average of corresponding world-space elevation coordinates of a set of image pixels associated with said elevation tile within a boundary defined by said plurality of corners.

3. A method of sensing a physical feature of or along a path of a vehicle as recited in claim 2 , further comprising selecting as a pitch/roll analysis patch a subset of elevation tiles associated with a region along said path that is relatively close in down-range to said vehicle and substantially laterally centered with respect to said vehicle.

4. A method of sensing a physical feature of or along a path of a vehicle as recited in claim 3 , further comprising determining said pitch angle of said vehicle responsive to at least one curve fit of world-space elevation values with respect to world-space down-range values of a subset of said subset of said elevation tiles associated with a substantially common cross-range location with respect to said vehicle, wherein said subset of said subset of said elevation tiles are associated with said pitch/roll analysis patch.

5. A method of sensing a physical feature of or along a path of a vehicle as recited in claim 3 , further comprising determining a roll angle of said vehicle responsive to at least one curve fit of world-space elevation values with respect to world-space cross-range values of a subset of said subset of said elevation tiles associated with a substantially common down-range location with respect to said vehicle, wherein said subset of said subset of said elevation tiles are associated with said pitch/roll analysis patch.

6. A method of sensing a physical feature of or along a path of a vehicle as recited in claim 2 , further comprising:
a. selecting at least one subset of said elevation tiles along at least one prospective tire track of at least one tire of said vehicle, and
b. communicating a plurality of measures responsive to at least one world-space elevation profile with respect to travel distance along a corresponding said at least one subset of said elevation tiles so as to provide for controlling a suspension system of said vehicle responsive thereto.

7. A method of sensing a physical feature of or along a path of a vehicle as recited in claim 6 , wherein said plurality of measures comprises at least one differential elevation profile associated with at least one corresponding said at least one prospective tire track, and each value of said at least one differential elevation profile is responsive to a difference of world-space elevation values of different elevation tiles of said at least one subset of said elevation tiles along said at least one corresponding said at least one prospective tire track.

8. A method of sensing a physical feature of or along a path of a vehicle as recited in claim 6 , wherein each value of said at least one world-space elevation profile is responsive to a weighted average of world space elevation values of a plurality of said elevation tiles for different cross-range locations within said at least one prospective tire track at a substantially common said travel distance along said at least one prospective tire track.

9. A method of sensing a physical feature of or along a path of a vehicle as recited in claim 6 , further comprising predicting a corresponding at least one location of said at least one prospective tire track responsive to measures of yaw rate and velocity of said vehicle.

10. A method of sensing a physical feature of or along a path of a vehicle as recited in claim 1 , wherein each light spot of said at least one pair of said plurality of light spots are at said different world-space down-range locations and are at a substantially common world-space cross-range location.

11. A method of sensing a physical feature of or along a path of a vehicle, comprising:
projecting a structured light pattern from a vehicle onto a path upon which said vehicle may travel, so as to generate a plurality of light spots on said path, wherein at least two of said plurality of light spots are at different world-space down-range locations relative to said vehicle;
capturing from said vehicle at least one image of said plurality of light spots using at least one camera;
determining at least two image-space locations in said at least one image of a corresponding said at least two of said plurality of lights spots at said different world space down-range locations;
determining a pitch angle of said vehicle responsive to said at least two of said plurality of light spots; and
determining corresponding world-space elevations of at least a portion of said plurality of light spots responsive to said pitch angle of said vehicle; and
wherein said at least one image is captured using a stereo-vision imaging system that provides for generating first and second stereo image components, each from a different perspective along a baseline separated by a baseline distance, further comprising:
a. determining a corresponding down-range location of each light spot of said plurality of light spots responsive to a disparity of image-space locations of said corresponding light spot in said first and second stereo image components, and
b. determining a corresponding world-space elevation of said light spot responsive to said corresponding dow

Assignees

• Tk Holdings Inc
• Joyson Safety Systems Acquisition Llc

Inventors

• Schamp Gregory Gerhard

Classifications

• G01B11/2545 Primary

  with one projection direction and several detection directions, e.g. stereo · CPC title

• G06V20/584

  of vehicle lights or traffic lights · CPC title

• B60W2552/35

  Road bumpiness, e.g. potholes · CPC title

• B60G2400/82

  Ground surface · CPC title

• B60W2552/05

  Type of road, e.g. motorways, local streets, paved or unpaved roads · CPC title