PURPOSE: To surely prevent rear-end collision when the car behind detected with a backward radar is brought off from a beam area at approaching this vehicle by synthetically judging a danger of rear-end collision based on data at existing in the beam area.
CONSTITUTION: A control circuit 16 controls to drive a backward sensor 20 through a driving circuit 22, and judges existence of the car behind in a prescribed distance based on the detected signal from the backward sensor 20. When the car behind exists, relative distance and speed between this vehicle and the car behind are computed based on the detected signal from a vehicle speed detecting circuit 10 for detecting the running speed of this vehicle. When a danger of rear-end collision exists at present by changing the advancing direction of this vehicle, a waning device 26 is actuated through a driving circuit 24, based on the detected signal from a steering angle detecting circuit 12 and the like. Further, when a danger of rear-end collision exists at changing the advancing direction after a prescribed time, a warning is given on confirming this.
YAMADA YUKINORI
AKUTSU EISAKU
