Fiber optic sensors and control systems for automobile occupant protection apparatus

• US 5,502,301 A
• Filed: 05/23/1994
• Issued: 03/26/1996
• Est. Priority Date: 05/23/1994
• Status: Expired due to Fees

• Current Assignee: Alcoa Fujikura Ltd. (Howmet Aerospace, Inc.)
• Original Assignee: Thomas & Betts Corporation (ABB Limited)
• Inventors: Lord, Randal B.
• Primary Examiner(s): Westin, Edward P.
• Assistant Examiner(s): LE, QUE TAN
• Application Number:
  US08/247,748
• Time in Patent Office: 673 Days
• Field of Search: 250/227.14, 250/227.15, 250/227.16, 250/227.24, 250/231.19, 73/794, 73/812, 73/813, 73/823, 340/665, 340/677, 340/555-557, 180/274, 280/735, 385/12, 385/13
• US Class Current: 250/227.14
• 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 1/243 using means for applying force perpendicular to the fibre axis

Abstract

A fiber optic sensor for the sensing of forces imposed on the sensor in a predetermined direction comprises a housing and an optical fiber of a type which is self-deformable in response to forces imposed on the sensor. The housing retentively engages first and second opposed ends of the fiber and places the fiber in tangential contiguity with an interior surface of the housing. The housing defines a cavity aside the fiber permitting movement of the fiber therein and distal from the tangential contiguity thereof with the interior surface. In the predetermined force imposition direction, the cavity is successive to the interior surface of the housing. A system is provided for generating an input signal for control of automobile occupant protection apparatus of an automobile having a preselected forward travelling direction, the system comprising first apparatus, inclusive of a first fiber optic sensor responsive to first forces imposed thereon in a first direction opposite the preselected forward travelling direction, for providing a first output indicative of characteristics of the first forces, second apparatus, inclusive of a second fiber optic sensor responsive to second forces imposed thereon in a second direction different from the direction opposite the preselected forward travelling direction, for providing a second output indicative of characteristics of the second forces and third apparatus responsive to the first and second outputs for selectively generating the input signal.

Claims

1. A fiber optic sensor for the sensing of forces imposed thereon in a predetermined direction, said sensor comprising a housing and an optical fiber of a type which is self-deformable in response to forces imposed on said sensor, said housing retentively engaging first and second opposed ends of said fiber and placing said fiber in tangential contiguity with an interior surface of said housing, said housing defining a cavity aside said fiber, permitting movement of said fiber therein distal from said tangential contiguity of said fiber with said housing interior surface, said cavity and said fiber being successive to said housing interior surface and the cavity being successive to the fiber in said predetermined force imposition direction.

2. The sensor claimed in claim 1 wherein said housing interior surface is in continuous tangential continuity with said fiber between said fiber first and second ends.

3. The sensor claimed in claim 1, wherein said fiber is comprised of a core and a cladding circumscribing said core, said core and cladding being constituted of flexible material.

4. The sensor claimed in claim 3, wherein said core and cladding are both constituted of an elastomeric material.

5. The sensor claimed in claim 1 further comprising a body supported in said housing interior surface in force-imposing relation to said fiber.

6. The sensor claimed in claim 5, wherein said housing interior surface is discontinuous, defining an opening therein, said body being disposed in said housing interior surface opening.

7. The sensor claimed in claim 6 further comprising a layer disposed on said housing interior surface exteriorly of said opening therein and retaining said body in said opening.

8. The sensor claimed in claim 6, wherein said body is a spherical body.

9. The sensor claimed in claim 1 further comprising first and second light couplers respectively disposed at said optical fiber first and second ends, light generating means in communication with said first light coupler and transmitting light therethrough into said optical fiber, light receiving means in communication with said second light coupler and generating an output signal indicative of characteristics of light received thereby from said second light coupler and comparator means for receiving said output signal generated by said light receiving means and generating a sensor output signal selectively in accordance with said characteristics indicated in said output signal.

10. A system generating an input signal for control of a triggering component of an automobile occupant protection apparatus of an automobile having a forward travelling direction, said system comprising:

(a) a fiber optic sensor for the sensing of forces imposed thereon in a predetermined direction opposite said forward travelling direction, said sensor comprising a housing and an optical fiber of a type which is self-deformable in response to forces imposed on said sensor, said housing retentively engaging first and second opposed ends of said fiber and placing said fiber in tangential contiguity with an interior surface of said housing, said housing defining a cavity aside said fiber permitting movement of said fiber therein and distal from said tangential contiguity of said fiber with said housing interior surface, said cavity being successive to said housing interior surface and the fiber in said predetermined force imposition direction;

(b) first and second light couplers respectively disposed at said optical fiber first and second ends;

(c) light generating means in communication with said first light coupler and transmitting light therethrough into said optical fiber;

(d) light receiving means in communication with said second light coupler and generating an output signal indicative of characteristics of light received thereby from said second light coupler; and

(e) comparator means for receiving said output signal generated by said light receiving means and generating said input signal selectively in accordance with said characteristics indicated in said output signal.

11. The system claimed in claim 10, wherein said housing interior surface is in continuous tangential continuity with said fiber between said fiber first and second ends.

12. The system claimed in claim 10, wherein said fiber is comprised of a core and a cladding circumscribing said core, said core and cladding being constituted of flexible material.

13. The system claimed in claim 12, wherein said core and cladding are both constituted of an elastomeric material.

14. The system claimed in claim 10 further comprising a body supported in said housing interior surface in force-imposing relation to said fiber.

15. The system claimed in claim 14, wherein said housing interior surface is discontinuous, defining an opening therein, said body being disposed in said housing interior surface opening.

16. The sensor claimed in claim 15 further comprising a layer disposed on said housing interior surface exteriorly of said opening therein and retaining said body in said opening.

17. The sensor claimed in claim 15, wherein said body is a spherical body.

18. The system claimed in claim 10 further comprising a second fiber optic sensor for the sensing of forces imposed thereon in a preselected direction different from said predetermined direction opposite said forward travelling direction.

19. The system claimed in claim 18, wherein said second fiber optic sensor includes a second optical fiber having first and second ends, said system further comprising third and fourth light couplers respectively disposed at said first and second ends of said second optical fiber, said system including a further light generating means in communication with said third light coupler and transmitting light therethrough into said second optical fiber, second light receiving means in communication with said fourth light coupler and generating an output signal indicative of characteristics of light received thereby from said fourth light coupler and further comparator means for receiving said output signal generated by said second light receiving means and generating an inhibit signal selectively in accordance with said characteristics indicated in said second light receiving means output signal is a predetermined characteristic,

said first-mentioned comparator means being rendered inoperative to generate said input signal upon receipt of said inhibit signal.

20. A system generating an input signal for control of a triggering component of an automobile occupant protection apparatus of an automobile having a preselected forward travelling direction, said system comprising:

(a) first means, inclusive of a first fiber optic sensor responsive to first forces imposed thereon in a first direction opposite said preselected forward travelling direction, for providing a first output signal indicative of characteristics of said first forces;

(b) second means, inclusive of a second fiber optic sensor responsive to second forces imposed thereon in a second direction different from said first direction for providing a second output signal indicative of characteristics of said second forces; and

(c) comparator means responsive to said first and second outputs for selectively generating said input signal.

21. The system claimed in claim 20, wherein said first means includes a housing supporting an optical fiber of said first fiber optic sensor, said housing being configured to render said optical fiber substantially unresponsive to forces imposed thereon other than said first forces.

22. The system claimed in claim 20, wherein said first means includes a housing supporting an optical fiber of said first fiber optic sensor, said housing being configured to render said optical fiber substantially unresponsive to forces imposed thereon other than said first forces.

23. A system generating an input signal for control of a triggering component of an automobile occupant protection apparatus of an automobile, said system comprising:

(a) first means, inclusive of a first fiber optic sensor responsive to first forces imposed thereon in a first direction for providing a first output indicative of characteristics of said first forces;

(b) second means, inclusive of a second fiber optic sensor responsive to second forces imposed thereon in a second direction different from said first direction for providing a second output indicative of characteristics of said second forces; and

(c) comparator means responsive to said first and second outputs for selectively generating said input signal.