Analysis of Accelerometer Data for Use in Skid-Stop Calculations

Several accelerometers are now commercially available and are becoming widely used by accident reconstructionists for determining the coefficient of friction or the “drag factor” using an exemplar vehicle at the accident site. To get a quick estimate of the effective coefficient of friction for the braking test, people often simply average the deceleration values in units of g (gravitational acceleration) from the accelerometer output of deceleration versus time. Since this involves an inherent error in method, it is of interest to examine the magnitude of this error.