Self-excited sound field type non-contact sensor sensing method and non-contact touch device

Abstract

The application discloses a sensing method of a self-excitation sound field type non-contact sensor and a non-contact touch control device, and relates to the technical field of sensors.The sensor comprises a vibrating body, a piezoelectric ceramic and a piezoelectric film arranged on the vibrating body.The sensing method comprises the following steps: the piezoelectric ceramic is driven to vibrate by an input excitation signal, and drives the vibrating body to generate bending vibration of the same frequency; the bending vibration of the vibrating body excites ultrasonic waves, and generates acoustic radiation force after being reflected by an obstacle within a set range; the piezoelectric film generates deformation under the influence of the acoustic radiation force, and outputs a voltage signal; and the amplitude of the voltage signal changes with the change of the amplitude of the bending vibration.Based on the acoustic radiation force of the ultrasonic sound field, the ultrasonic waves are continuously emitted to generate a sound field between the sensor and the obstacle, the non-contact sensing is realized by detecting the influence of the acoustic radiation force of the sound field on the vibration displacement of the sensor, and the non-contact human-computer interaction in a vehicle is further realized.

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