Patent ID: 8031556

Claim:
An obstacle detection apparatus for a vehicle, the apparatus comprising: an ultrasonic sensor that detects a presence of an obstacle around the vehicle and a distance to the obstacle by transmitting an ultrasonic wave and receiving the ultrasonic wave reflected by the obstacle; and a controller that controls the ultrasonic sensor, wherein: the ultrasonic sensor includes an ultrasonic wave element; the ultrasonic wave element has a plurality of resonance modes; the ultrasonic sensor changes a directivity of the ultrasonic sensor by selecting one of the plurality of resonance modes of the ultrasonic wave element in accordance with a command signal output from the controller; the ultrasonic sensor changes a sensing distance of the ultrasonic sensor in accordance with the command signal output from the controller; the controller is configured to command the ultrasonic sensor to change the directivity and the sensing distance of the ultrasonic sensor when a predetermined condition is met after an obstacle detection operation is started; and the controller is configured to command the ultrasonic sensor to change the directivity and the sensing distance of the ultrasonic sensor based on the distance to the obstacle detected with the ultrasonic sensor.