A Novel Approach for Exploring Resolution Tunable Displacement Measurement System by Using Extension Spring and Ultrasonic Sensors

In this letter, we proposed an ultrasonic sensor-based resolution tunable displacement measurement system by using an extension spring. In the proposed method, a linear extension spring is vertically suspended between two clamps. The top end of the clamp is fixed, while the bottom end of the clamp is movable. An ultrasonic sensor is mounted on top of the arrangement. A circular reflective metallic plate is fixed at certain number of active coils of the spring to reflect the ultrasonic waves. It is experimentally observed that with the change in position of the reflective plate on the spring, there is a change in resolution of measured displacement. The proposed method has novelty of having capability to tune the resolution, free of hysteresis, simple in design, and having response time less than 1 s.