Force-displacement measurement using simultaneous phase-shifting technique

This paper presents a novel simultaneous phase-shifting technique for force-displacement measurement. A demonstration with instantaneous 4-step phase shift for measuring displacement through shadow moire is reported. The merits of the proposed technique consist of fewer signal wires and less susceptibility to electromagnetic waves and vibrations. The experimental results show that the proposed design has a good linear relationship between the force and the displacement, leading to various applications, such as tactile sensors. (C) 2019 The Japan Society of Applied Physics