Vehicular Ranging System and Method of Operation

• US 20120242972A1
• Filed: 03/23/2012
• Published: 09/27/2012
• Est. Priority Date: 03/25/2011
• Status: Active Grant

• Current Assignee: Jay Young Wee
• Original Assignee: Jay Young Wee
• Inventors: Wee, Jay Young
• Granted Patent: US 9,897,700 B2
• Time in Patent Office: Days
• US Class Current: 356/4.01
• 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 7/486 Receivers

Abstract

A vehicular object ranging system having a long-range sensor having a long-range field of view and a short-range sensor having a short-range field of view overlapping and exceeding said long-range field of view and having an angular resolution capability. The sampling rate of one of the long-range sensor and short-range sensor can be varied depending of the signal provided by the other.

Claims

1. A method of operating a vehicular object ranging system having a long-range laser LIDAR system having a long-range field of view and a long-range depth, and a short-range laser LIDAR system having a short-range field of view overlapping and exceeding said long-range field of view and a short-range depth smaller than said long-range depth, said method comprising operating one of said long-range sensor and said short-range sensor While simultaneously maintaining the other one of said long-range sensor and said short-range sensor in one of a reduced activation mode and an inactive mode.

2. A method of operating a vehicular object ranging system having a long-range sensor having a long-range field of view and a short-range sensor having a short-range field of view overlapping and exceeding said long-range field of view and having an angular resolution capability, said method comprising:

operating the long-range sensor at a long-range sampling rate to generate at least one indication of one of an absence and a range of an object within said long-range field of view;

operating the short-range sensor at a short-range sampling rate to generate at least one indication of one of an absence and a range of an object within said short-range field of view; and

varying the sampling rate of one of the long-range sensor and the short-range sensor based on the at least one indication provided by the other one of the long-range sensor and the short-range sensor.

3. The method of claim 2 wherein the long-range sensor is a long-range LIDAR system having a long-range depth, and the short-range sensor is a short-range LIDAR system having a short-range depth smaller than said long-range depth.

4. The method of claim 2 wherein the step of varying includes reducing the sampling rate.

5. The method of claim 2 wherein the step of varying is further based on determining that a speed of the vehicle is one of above and below a given value.

6. The method of claim 2 wherein the step of varying is further based on determining a favourable state of weather conditions.

7. The method of claim 2 wherein the step of varying includes reducing the sampling rate of the long range sensor based on the short range sensor generating at least one indication a range of an object within said short-range field of view, said indication further including an indication that the object totally covers the long-range field of view.

8. The method of claim 7 wherein the step of varying is further based on determining that a speed of the vehicle is below a threshold value.

9. The method of claim 7 wherein said reducing includes stopping the sampling of the long-range subsystem while maintaining the sampling rate of the short range subsystem at a maximal value.

10. The method of claim 2 wherein the step of varying includes reducing the sampling rate of the short range sensor based on an indication of absence of an object from both the short range sensor and the long range sensor.

11. The method of claim 2 wherein the step of varying includes reducing of the sampling rate of the short-range sensor based on the long-range sensor generating an indication of a range of an object and the short-range sensor generating an indication of an absence of an object in the short range field of view.

12. The method of claim 11 wherein said reducing is further based on an indication that a vehicle speed exceeds a minimum value.

13. The method of claim 2 further comprising evaluating the relative speed of an object in the long range field of view based on at least two indications of range of an object of the long-range sensor;

comparing the relative speed of an object to an incoming speed threshold value; and

wherein the step of varying includes reducing the sampling rate of the short range sensor based on determining that the relative speed of an object is below the incoming speed threshold value.

14. A vehicular object ranging system having a housing containing a long-range sensor having a long-range field of view and a long-range depth and a short-range sensor having a short-range field of view overlapping and exceeding said long-range field of view and a short-range depth smaller than said long-range depth, and a control module having a function to operate one of said long-range sensor and said short-range sensor while simultaneously maintaining the other one of said long-range sensor and said short-range sensor in one of a reduced activation mode and an inactive mode.

15. The vehicular object ranging system of claim 14 wherein

the short range sensor is a short-range laser LIDAR subsystem operable within a range of short-range sampling rates, including at least one emitter and a receiver, a mechanism to determine sampling rate of said subsystem, and the capability to provide the angular position and horizontal angular dimension within the field of view of objects detected and the range of the objects detected,

the long range sensor is a long-range laser LIDAR subsystem operable within a range of long-range sampling rates, including at least one emitter and a receiver, a mechanism to determine a sampling rate of said subsystem, and the capability to provide the range of objects detected within the long-range field of view, and

the control module is capable of acquiring an indication of absence and range of objects from the short range laser LIDAR subsystem and the long range laser LIDAR subsystem, and capable, based on this acquired information, to vary the sampling rate of the abovementioned subsystems.

16. The vehicular object ranging system of claim 15 wherein each one of the laser LIDAR subsystems includes a corresponding emitter and a corresponding receiver, and a lidar output for lidar arrayed data acquired from the lidar receiver, and is further associated to a corresponding video camera subsystem.