Study of Soft Force and Displacement Sensor Based on Dielectric Elastomer

With the desirable physical performances of high strain and low stiffness, a novel soft sensor based on the dielectric elastomer (DE) material shows great potential in the wearable devices and soft robots. Since the DE material has the complex nonlinear characteristics and the electromechanical coupling, most early works only devoted to the sensor structure design. However, the studies on the mathematical modeling of the DE sensor (DES) are insufficient. In this paper, a mathematical model of the soft sensor based on the DE material is built to describe its sensing property. Because the DES is used to measure the displacement and force simultaneously, it can serve as a soft force and displacement sensor (SFDS). Based on the experimental data, the differential evolution algorithm is employed to identify the undetermined parameters of the developed mathematical model of the SFDS. The result of model validation demonstrates the effectiveness of the model.