Occupant sensor

• US 6,961,443 B2
• Filed: 06/15/2001
• Issued: 11/01/2005
• Est. Priority Date: 06/15/2000
• Status: Active Grant

• Current Assignee: Joyson Safety Systems Acquisition, LLC
• Original Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Mahbub, Naveed
• Primary Examiner(s): Mehta, Bhavesh M.
• Assistant Examiner(s): Strege, John
• Application Number:
  US09/882,959
• Publication Number:
  US 20020050924A1
• Time in Patent Office: 1,600 Days
• Field of Search: 382/100, 382/103, 382/104, 382/154, 382/106, 701/45, 280/735, 250/559.19, 250/559.35, 250/559.38, 348/143, 348/148, 348/159, 348/169, 348/172, 340/436, 340/438, 340/439
• US Class Current: 382/100
• CPC Class Codes: B60R 21/01538 for image processing, e.g. cameras or sensor arrays
• CPC Class Codes: G01S 17/04 Systems determining the presence of a target
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 7/4802 using analysis of echo signal for target characterisation; Target signature; Target cross-section
• CPC Class Codes: G06T 7/00 Image analysis
• CPC Class Codes: G06T 7/70 Determining position or orientation of objects or cameras camera calibration G06T7/80
• CPC Class Codes: G06V 40/103 Static body considered as a whole, e.g. static pedestrian or occupant recognition

Abstract

An occupant sensor incorporates a 3-D imaging system that acquires a 3-D image of an object. The image is segmented to remove unwanted portions and to identify a region-of-interest, and the content thereof is classified responsive to a plurality of 3-D features. In one embodiment, the 3-D image is transformed to a second 3-D image from a second viewing perspective. A two-dimensional projection of the second 3-D image is classified, and a presence, size and position of occupant can be identified from features thereof. A safety restraint system is controlled responsive to the detected scenario, including the presence, position and size of an occupant.

Claims

1. A method of sensing an occupant in a vehicle, comprising:

a. providing for acquiring a first three-dimensional image of a scene from a first viewing perspective;

b. providing for segmenting said first three-dimensional image so as to identify a region-of-interest in said first three-dimensional image;

c. providing for forming a second three-dimensional image by removing a portion of said first three-dimensional image that is outside of said region-of-interest; and

d. providing for classifying a scenario responsive to an image content of said second three-dimensional image, wherein said image content is represented by a plurality of three-dimensional features selected from a volumetric central moment, a centroid, a volume, a volumetric roundness, a ratio of radii, a volume of a bounding cube, a ratio of volumes and a percentage of volume occupied.

2. A method of sensing an occupant in a vehicle as recited in claim 1, wherein said portion of said first three-dimensional image that is outside of said region-of-interest comprises a portion of an image of an object selected from a dashboard of the vehicle, an interior of a side door of a vehicle, a scene outside a window of the vehicle, a floor of the vehicle, and a structural pillar in the vehicle.

3. A method of sensing an occupant in a vehicle as recited in claim 1, wherein said operation of classifying comprises detecting the presence of an occupant from a plurality of said features of said second three-dimensional image.

4. A method of sensing an occupant in a vehicle as recited in claim 3, further comprising providing for tracking said occupant from one image frame to another.

5. A method of sensing an occupant in a vehicle as recited in claim 3, further comprising providing for detecting whether said occupant is located in an at-risk zone proximate to a safety restraint system.

6. A method of sensing an occupant in a vehicle as recited in claim 3, further comprising providing for determining a size of said occupant from at least one feature of said second three-dimensional image.

7. A method of sensing an occupant in a vehicle as recited in claim 1, further comprising providing for controlling a safety restraint system responsive to said operation of classifying a scenario.

8. A method of sensing an occupant in a vehicle, comprising:

a. providing for acquiring a first three-dimensional image of a scene from a first viewing perspective;

b. providing for transforming said first three-dimensional image to a second three-dimensional image from a second viewing perspective;

c. providing for segmenting either said first three-dimensional image prior to said transforming operation, or said second three-dimensional image, so as to identify a region-of-interest in said first or said second three-dimensional image;

d. providing for forming a third three-dimensional image by removing a portion of said first or said second three-dimensional image that is outside of said region-of-interest; and

e. providing for classifying a scenario responsive to an image content of said third three-dimensional image, wherein said image content comprises a two-dimensional representation of said third three-dimensional image.

9. A method of sensing an occupant in a vehicle as recited in claim 8, wherein said portion of said first or said second three-dimensional image that is outside of said region-of-interest comprises a portion of an image of an object selected from a dashboard of the vehicle, an interior of a side door of a vehicle, a scene outside a window of the vehicle, a floor of the vehicle, and a structural pillar in the vehicle.

10. A method of sensing an occupant in a vehicle as recited in claim 8, wherein said image content is represented by at least one two-dimensional feature selected from a central moment, a normalized central moment, an invariant moment, a perimeter, and area, a roundness, a bending energy, an orientation, an area of a bounding rectangle, a best fit ellipses, and eccentricity of a region of interest, a ratio of areas, and a central axis line.

11. A method of sensing an occupant in a vehicle as recited in claim 10, wherein said operation of classifying comprises detecting the presence of an occupant from a plurality of said features of said third three-dimensional image.

12. A method of sensing an occupant in a vehicle as recited in claim 11, further comprising providing for tracking said occupant from one image frame to another.

13. A method of sensing an occupant in a vehicle as recited in claim 11, further comprising providing for detecting whether said occupant is located in an at-risk zone proximate to a safety restraint system.

14. A method of sensing an occupant in a vehicle as recited in claim 11, further comprising providing for determining a size of said occupant from at least one feature of said third three-dimensional image.

15. A method of sensing an occupant in a vehicle as recited in claim 8, further comprising providing for controlling a safety restraint system responsive to said operation of classifying a scenario.