Patent US 5,570,087

A system and method are disclosed for monitoring the performance of a motor vehicle. The vehicle's instantaneous accelerations in at least two directions are continually sensed and stored as coded signals in a computer memory. Performance variables of the vehicle are computed from the acceleration signals stored in memory along with associated time and date codes. By means of inertial navigation and/or radio transmissions from global positioning system satellites, the vehicle's global position is also computed and stored. The stored performance variables are analyzed over a period of time in order to evaluate how the vehicle is being driven. When an erratic or otherwise hazardous driving pattern is detected, signals may be generated to warn the driver and/or traffic authorities.