Method and apparatus for sensing a vehicle crash in real time using a frequency domain summation algorithm

Abstract

A method and apparatus is disclosed for controlling actuation of a passenger restraint system in a vehicle. The apparatus includes an accelerometer for providing a time domain vibratory electric signal having frequency components indicative of a vehicle crash condition. An A/D converter converts the accelerometer signal into a digitized signal. A fast Fourier transform device transforms the digitized time domain vibratory electric signal over at least two time intervals into frequency domain signals. The amplitudes of corresponding frequency bins of the frequency domain signals are summed over the entire frequency spectrum, bin-to-bin. A microcomputer monitors the sum of the amplitudes of at least one selected frequency bin of the frequency domain signals and actuates the passenger restraint system when the sum is greater than a predetermined threshold thereby indicating a particular type of vehicle crash is occurring.

Dependencies are inferred from the claim text.