Collision deformation sensor using a source of wave energy for use in the crush zone of a vehicle

• US 6,607,212 B1
• Filed: 04/27/2001
• Issued: 08/19/2003
• Est. Priority Date: 11/26/1998
• Status: Expired due to Fees

• Current Assignee: Canpolar East Inc.
• Original Assignee: Canpolar East Inc.
• Inventors: Baldwin, Lorna H., Reimer, Ernest M.
• Primary Examiner(s): Morris, Lesley D.
• Assistant Examiner(s): LUM VANNUCCI, LEE SIN YEE
• Application Number:
  US09/830,638
• Time in Patent Office: 844 Days
• Field of Search: 280/735, 701/45, 180/274
• US Class Current: 280/735
• CPC Class Codes: B60R 21/0136 responsive to actual contact with an obstacle , e.g. to vehicle deformation, bumper displacement or bumper velocity relative to the vehicle monitoring crash strength in combination with passenger seat detection B60R21/01558
• CPC Class Codes: G01L 1/24 by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet

Abstract

A collision deformation sensor for use within the crush zone of a vehicle consists of first and second spaced apart substrates for mounting to or forming respective vehicle components, with a compressible carrier medium filling the space between the substrates. The carrier medium is formed from a material transparent or translucent to light or other wave energy, and includes wave energy scattering centers dispersed within the medium to create a scattered energy volume. Alternatively the carrier medium forms a hollow cavity, the inside surface of which is coated with a wave energy dispersion coating. A source and receiver of light or other wave energy communicates with the carrier medium. Signal couplings and processors are associated with the source and receiver. The device operates on the principle whereby compression of the space between the substrates increases the intensity of a light or other wave energy, and this increase is detected by the receiver and signal processor, which in turn activates an air bag, or seat belt tightener or the like.

Claims

1. A collision deformation sensor for mounting within a crush zone of a vehicle, said sensor comprising first and second spaced apart substrates (26, 28) within said vehicle crush zone and a means for detecting convergence of said substrates indicative of crushing of said crush zone and generating an electronic signal in response thereto, and means (10) responsive to said electronic signal for actuating an occupant restraint system;

characterized by said means for detecting convergence comprising;

a) a compressible carrier medium (2) of wave energy transmitting material having wave energy scattering centers disbursed therein;

b) a wave energy source (4, 6) in communication with said carrier medium, to beam wave energy into said medium, to provide a scattered energy volume within said medium containing fully scattered wave energy;

c) a wave energy receiver (8) for detecting an intensity of said fully scattered wave energy; and

d) signal coupling means (8) to operatively connect said receiver with signal processing means (10) for triggering said occupant restraint system when said receiver detects a change in said intensity indicating a converging of said substrates, and a consequent compression of said carrier medium, at or above an extent indicative of a severe impact of said vehicle.

2. A method for detection of an impact against a vehicle and providing a response comprising the steps of providing a vehicle having incorporated therein a deformation sensor within a crush zone of said vehicle and communicating between said sensor and an occupant restraint system when said sensor detects a severe impact, characterized by the steps of:

a) providing a deformation sensor as defined in claim 1 within said vehicle linking two substrates within the crush zone of said vehicle;

b) transmitting light from a source to a light-transparent deformable carrier medium (2) having light scattering centers evenly disbursed throughout, to form an optical cavity defined by a region with said medium within which light from said source is fully scattered;

c) detecting the intensity of fully scattered and integrated light within said optical cavity and transmitting a resulting signal to signal processing means;

d) converting within said signal processing means (10) said resulting signal into an output electrical signal;

e) actuating an occupant restraint system (124, 126) upon detection fo a change in said integrated light intensity within said optical cavity indicative of converging together of said substrates by an extent indicative of a severe impact experienced by said vehicle.

3. A sensor as defined in claim 1, wherein said wave energy source and receiver comprise respectively a source and receiver of visible light.

4. A sensor as defined in claim 3, wherein said wave energy source and receiver comprise respectively a fiber optic light source and receiver.

5. A sensor as defined in claim 4 wherein said light source and receiver comprise a generally linear array (16) of pairs of light sources and receivers respectively.

6. A sensor as defined in claim 3, wherein said light source and receiver comprise an LED and photo receptor (154), respectively, mounted to a circuit board (152) in contact with said carrier medium.

7. A sensor as defined in claim 3 wherein said light source and receiver comprise a generally linear array (16) of pairs of light sources and receivers respectively.

10. A vehicle as defined in claim 7, wherein said energy source and receiver comprise respectively a fiber optic light source and receiver.

11. A vehicle as defined in claim 10, wherein said light source and receiver comprise a generally linear array (16) of pairs of light sources and receivers.

12. A vehicle as defined in claims 7, wherein said light source and receiver comprise a generally linear array (16) of pairs of light sources and receivers.

18. A vehicle as defined in any of claim 13-17 or 8-12 wherein said carrier medium comprises an energy absorbing foam material.

8. A vehicle having integrated therein a collision detector within a crush zone of said vehicle, said crush zone comprising a first substrate (28) at the periphery of said vehicle and a second substrate (26) spaced apart from and inboard of said first substrate, and sensor means between said first and second substrates to detect convergence of said first and second substrates indicative of crushing of said crush zone, characterized by said sensor means comprising:

a) a compressible carrier medium (2) of wave energy transmitting material having wave energy scattering centers disbursed within said carrier medium;

b) a wave energy source (4, 6) coupled to the carrier medium to create a scattered energy volume containing fully scattered wave energy;

c) a wave energy receiver (8) responsive to an intensity of said fully scattered wave energy; and

d) signal coupling means (10) to operatively connect said receiver with signal processing means for triggering said occupant restraint system when said receiver detects a change in said intensity indicating a converging of said substrates, and a consequent compression of said carrier medium indicative, at or above an extent indicative of a severe impact of said vehicle.

9. A vehicle as defined in claim 8, wherein said wave energy source and receiver comprise respectively a source and receiver of visible light.

13. A vehicle as defined in claim 9, wherein said light source and receiver comprise an LED and photo receptor (154), respectively, mounted to a circuit board (152) in contact with said carrier medium.

14. A vehicle as defined in claim 8, wherein said first substrate comprises a bumper skin (28) and said second substrate comprises a bumper armature (26), said carrier medium comprising a compressible foam material (2) at least partly filling the space between said armature and skin.

15. A vehicle as defined in claim 8, wherein said first substrate comprises a door panel skin (44) said second substrate comprising a door panel support structure (42) spaced apart from said support structure, the interior volume therebetween substantially filled with said carrier medium (2).

16. A vehicle as defined in claim 8, wherein said first substrate comprises a portion of a vehicle skin (44), and said second substrate comprises a portion of a vehicle frame (42) spaced apart from said frame, said carrier medium comprising compressible foam at least partly filling said space between said frame and skin.

17. A vehicle as defined in claim 8, said first substrate comprising a first component of a vehicle structural frame element (52) and said second substrate comprising a second component of said frame element, said first and second components defining an interior volume therebetween substantially filled with said carrier medium.