Vehicle signal apparatus

Claim 1

Signal apparatus for a following vehicle comprising, in combination: sensing means on the following vehicle for periodically determining actual forward velocity and position parameters of the following vehicle and a lead vehicle moving ahead of the following vehicle in the same direction; calculating means on the following vehicle for (1) deriving, from initial predicted forward velocity and position parameters of the lead and following vehicles, subsequent predicted forward velocity and position parameters of the lead and following vehicles and a subsequent predicted distance D(t) between the lead vehicle and the following vehicle after a projected short time interval while assuming predetermined braking actions of the lead vehicle and the following vehicle, (2) deriving and comparing the subsequent predicted distance D(t) between the lead vehicle and the following vehicle with a least distance D LEAST , and (3) setting the least distance D LEAST equal to the subsequent predicted distance D(t) between the lead vehicle and the following vehicle if the latter is smaller; control means effective, after each periodic determination of the actual forward velocities and positions by the sensing means, for iteratively applying the calculating means, the control means using the actual forward velocity and position parameters determined by the sensing means as the initial predicted forward velocity and position parameters in the first iteration and further using the subsequent predicted forward velocity and position parameters from each iteration as the initial predicted forward velocity and position parameters in the next iteration; and signal means for generating a signal if and when the least distance D LEAST becomes smaller than a minimum allowable distance D MIN .