Vehicle occupancy detection using time-of-flight sensor

• US 9,964,643 B2
• Filed: 12/08/2011
• Issued: 05/08/2018
• Est. Priority Date: 12/08/2011
• Status: Active Grant

• Current Assignee: Conduent Business Services, LLC (Conduent, Inc.)
• Original Assignee: Conduent Business Services, LLC (Conduent, Inc.)
• Inventors: Maeda, Patrick Yasuo
• Primary Examiner(s): Koziol, Stephen R
• Assistant Examiner(s): SCHWARTZ, RAPHAEL M
• Application Number:
  US13/315,016
• Publication Number:
  US 20130148845A1
• Time in Patent Office: 2,343 Days
• CPC Class Codes: G01S 17/86 Combinations of lidar systems with systems other than lidar, radar or sonar, e.g. with direction finders
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G08G 1/04 using optical or ultrasonic detectors

Abstract

Vehicle occupancy detection involves projecting modulated light onto an occupant from a light source outside of a vehicle. Reflections of the light source are received at a detector located outside of the vehicle. Three-dimensional data is determined based on a time-of-flight of the reflections, and the occupant is detected based on the three-dimensional data.

Claims

1. A method comprising:

projecting modulated light onto an occupant from a plurality of light sources outside of a vehicle;

receiving reflections of the light sources at a plurality of detectors having different views and located outside of the vehicle, the vehicle moving relative to the light sources and the detectors;

determining three-dimensional data based on a time-of-flight of the reflections; and

detecting the occupant using the three-dimensional data comprising combining the outputs of the plurality of detectors to correlate occupant detection data.

2. The method of claim 1, wherein detecting the occupant comprises recognizing a face of the occupant.

3. The method of claim 1, wherein detecting the occupant comprises recognizing an outline of the occupant.

4. The method of claim 1, wherein detecting the occupant comprises determining a count of occupants in the vehicle.

5. The method of claim 1, wherein at least one of the light sources and the detectors are part of an apparatus of a traffic monitoring system.

19. The method of claim 1, further comprising:

determining a location of a window of the vehicle using an intensity imaging device.

6. An apparatus comprising:

a plurality of light sources configured to project modulated light onto an occupant from outside of a vehicle that is moving relative to the light sources;

a plurality of detectors configured to receive reflections of the light, the detectors fixed relative to the light sources and having different views;

a processor coupled to the light sources and the detectors, the processor configured to;

determine time-of-flight of the reflections;

determine three-dimensional data of an interior of the vehicle based on the time-of-flight of the reflections; and

detect the occupant using the three-dimensional data; and

a correlator configured to combine the outputs of the plurality of detectors.

7. The apparatus of claim 6, wherein detecting the occupant comprises recognizing a face of the occupant.

8. The apparatus of claim 6, wherein detecting the occupant comprises recognizing an outline of the occupant.

9. The apparatus of claim 6, wherein detecting the occupant comprises determining a count of occupants in the vehicle.

10. The apparatus of claim 6, further comprising an imaging device configured to set one or more parameters of the light sources.

11. The apparatus of claim 6, wherein the apparatus is part of a traffic monitoring system.

12. A system comprising:

time-of-flight sensors configured to detect objects in an interior of a vehicle from outside of the vehicle that is moving relative to the time-of-flight sensors, the time of flight sensors projecting modulated light onto the vehicle and determining time-of-flight data based on reflections of the light detected by a plurality of detectors having different views; and

a computing arrangement coupled to the time-of-flight sensors, the computing arrangement having a processor configured to;

receive the time-of-flight data from the time-of-flight sensors;

correlate the different views of time-of-flight data;

detect an occupant of the vehicle using the correlated time-of-flight data; and

signal the detection of the occupant to an end-user application.

13. The system of claim 12, wherein detecting the occupant comprises recognizing a face of the occupant.

14. The system of claim 12, wherein detecting the occupant comprises recognizing an outline of the occupant.

15. The system of claim 12, wherein detecting the occupant comprises determining a count of occupants in the vehicle.

16. The system of claim 12, wherein the user application comprises a traffic monitoring system.

17. The system of claim 12, where the data received from the time-of-flight sensors comprises a sequence of frames each having three-dimensional data.

18. The system of claim 17, wherein detecting the occupant comprises combining two or more of the frames to form an improved three-dimensional model based on the three-dimensional data.