Pedestrian impact sensor system

• US 6,212,456 B1
• Filed: 04/23/1999
• Issued: 04/03/2001
• Est. Priority Date: 04/24/1998
• Status: Expired due to Term

• Current Assignee: Jaguar Land Rover Limited (TATA Motors Limited)
• Original Assignee: Jaguar Cars Limited (TATA Motors Limited)
• Inventors: Stride, Kevin John
• Primary Examiner(s): Zanelli, Michael J.
• Application Number:
  US09/298,346
• Time in Patent Office: 711 Days
• Field of Search: 701/36, 701/45, 701/47, 280/728.1, 280/727, 280/762, 340/436, 180/274
• US Class Current: 701/45
• CPC Class Codes: B60R 19/483 with obstacle sensors of electric or electronic type
• CPC Class Codes: B60R 21/0134 responsive to imminent contact with an obstacle , e.g. using radar systems
• 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: B60R 21/34 Protecting non-occupants of a vehicle, e.g. pedestrians B60R19/02 takes precedence

Abstract

A pedestrian impact sensor system for a motor vehicle comprises sensor (4) for measuring the loads acting simultaneously on different regions across the front of the vehicle to produce pressure patterns (12a and 12b). The system includes a signal processor (14) for monitoring changes in measured pressure patterns over time, and for comparing these changes with data characteristic of pedestrian collisions. If a correspondence is identified, a signal is sent to activate a cushioning device (16).

Claims

1. A pedestrian impact sensing system for a motor vehicle comprising:

a front end assembly mounted on a front end of the vehicle;

a cushioning device mounted to the vehicle;

memory means for storing pressure pattern data characteristic of pedestrian collisions;

sensing means for measuring the loads acting simultaneously on different regions across the front end assembly to produce a pressure pattern;

means for monitoring changes in measured pressure patterns over time;

means for comparing the changing pressure patterns with stored pressure pattern data; and

means for sending a triggering signal for activating the cushioning device when a correspondence is identified between the monitored changing pressure pattern and stored pressure pattern data.

2. A pedestrian impact sensing system as claimed in claim 1, wherein the front end assembly includes a bumper assembly and the sensing means is housed in the bumper assembly.

3. A pedestrian impact sensing system as claimed in claim 2, wherein the bumper assembly includes a rigid bumper beam and a bumper cover, and the sensing means is sandwiched between the rigid bumper beam and the bumper cover.

4. A pedestrian impact sensing system as claimed in claim 3, wherein the bumper assembly further includes an energy absorbing module that is held in compression between the bumper cover and the sensing means.

5. A pedestrian impact sensing system as claimed in claim 4, wherein the bumper assembly is provided with a plurality of discrete loading features, each corresponding to a region of the bumper assembly where an element of the pressure pattern is to be measured.

6. A pedestrian impact sensing system as claimed in claim 5, wherein the loading features comprise nubs or projections on the energy absorbing module.

7. A pedestrian impact sensing system as claimed in claim 1, wherein the sensing means comprises a pressure sensitive matrix.

8. A pedestrian impact sensing system as claimed in claim 1, wherein the means for comparing comprises a neural network.

9. A pedestrian impact sensing system as claimed in claim 1, further including means for detecting relative movement between the vehicle and an external object, means for producing a signal in response to detection of this movement, and means for increasing system resources available to the comparison means in response to the signal.

10. A method for detecting pedestrian impact with a motor vehicle, comprising:

measuring loads acting simultaneously across the front of the vehicle to produce a pressure pattern;

monitoring changes in measured pressure patterns over time;

comparing the changing pressure patterns with stored data for changing pressure patterns characteristic of pedestrian collisions to determine if there is a correspondence; and

sending a triggering signal to activate a cushioning device if a correspondence is identified.

11. A pedestrian protection system for a motor vehicle, comprising:

a cushioning device for cushioning an impact with a pedestrian, being actuatable by a triggering signal;

sensing means for measuring the loads acting simultaneously on different regions across the front of the vehicle to produce a pressure pattern;

means for monitoring changes in measured pressure patterns over time;

means for comparing the changing pressure patterns with stored data for changing pressure patterns characteristic of pedestrian collisions; and

means for sending a triggering signal to the cushioning device when a correspondence is identified between a measured changing pressure pattern and stored data.