This system maintains the vehicle at the speed the driver has set, as long as there are no vehicles in front in the same lane. If the system detects a vehicle being driven in front at a slower speed than one’s own vehicle while the driver is driving at a set speed, it closes the throttle valve to decelerate. If additional deceleration is necessary, it shifts the gears down to decelerate. If further deceleration is necessary, the system controls the brake actuator in order to apply the brakes. Then, the system maintains the vehicle-to-vehicle distance that has been set by the driver.
Thereafter, if there are no vehicles being driven in front within the set vehicle-to-vehicle distance because either the vehicle in front or one’s own vehicle has changed lanes, the system accelerates slowly to reach the set speed and resumes driving at the set speed.
(1)Laser radar sensor
There is a laser emitting portion, laser receiving portion, and the CPU in the laser radar sensor. The laser beams emitted by the laser emitting portion are radiated forward.
Then, the laser beams are reflected by the reflectors of the vehicle that is driven in front. The duration that the reflected beams return to the laser receiving portion is calculated by the CPU.
This sensor determines the distance between the vehicle and the vehicle in front. Then, it calculates the relative speed. These data are then transmitted to the distance control ECU. This sensor is designed so that it does not react to non-moving objects.
(2)Distance control ECU
Determines which vehicle to follow based on the information provided by the laser radar sensor, calculates the target acceleration signals for following the vehicle, and transmits an acceleration/deceleration request, shift-down request, warning buzzer request, and brake request to the engine and ECT ECU, and skid control ECU.