Ultrasonic measuring system

摘要

An ultrasonic measuring system detecting state informations of a vehicle other than a vehicle speed. An ultrasonic transducer TR1 directly detects the vehicle speed. A second ultrasonic transducer and a third ultrasonic transducer are disposed respectively in front of and at a back of a rotational center of the vehicle and separated from each other at a predetermined distance. They respectively transmit ultrasonic waves at right angles to the running direction of the vehicle and respectively at second and third predefined down-angles relative to the road. A two-dimensional speed of the vehicle can be measured on the basis of the speeds obtained by the transducers TR2 and TR3.