A new method of position measurement using ultrasonic array sensor without angular scanning

A new positional measurement method without angular scanning has been proposed for micromachined ultrasonic array sensors with high Q-value. In this method, the arrival time of wave fronts are detected by monitoring measured data points in phaser diagram and the direction and the distance between the objects and the sensor are determined. A conventional angular scanning method with delay and summation algorithm cannot be utilized with an array sensor with scattered resonant frequencies because the synthesized waveform is strongly distorted by the interference. The proposed method has been applied to the data from the array sensor elements with scattered resonant frequencies and object position measurement in air has been successfully realized.