A Magnetically Damped Crash Sensor Providing Testability and Dynamic System Reconfiguration

A magnetically damped and biased automobile crash sensor is described. The sensor is configured to provide an optimal balance between spring-mass and damped response characteristics. It is testable by the on-board diagnostic module at vehicle start-up, and deficiencies identified in the vehicle safety system may be mitigated by system reconfiguration, accomplished by automatic recalibration of unaffected sensors.

The test and recalibration features provide enhanced levels of safety and reliability to vehicle occupants. They also offer vehicle manufacturers and service technicians the benefit of automatic diagnosis to the component level, making full and regular verification of mechanical sensors and wiring for airbag systems possible for the first time.

These features also make this type of sensor ideal as a safing sensor for a system employing electronic crash discrimination techniques. If the electronic sensor fails or is disturbed by EMI, the magnetically controlled safing sensor can assume the crash discrimination task until the upset is corrected, with minimal reduction in occupant safety.