Development of a disposable Silicone-Graphite composite strain sensor for soft robotics applications

Abstract

This work proposes a disposable and flexible strain sensor based on Silicone-graphite composite alternative method for strain sensing applications in soft robotic systems. Flexible piezoresistive have emerged as a promising class of sensors due to their exceptional ability to convert mechanical loads electrical output responses. For this purpose, a sensing structure is fabricated using low-cost, disposable, easy-to-fabricate materials, with graphite powder of particle size 16-60 mu m and Silicone being chosen main fabrication materials. Therefore, an innovative material composed of Silicone and graphite is introduced, functioning as a flexible strain sensor. The sensor is formed in a bone-shaped clamped-clamped beam rectangular cross-sectional area (4 x 3 mm). A simple electronic read-out circuitry is also implemented system. The proposed flexible strain sensor structure is shown to be capable of measuring a force resolution 0.22292 mN. The minimum detectable force of the implemented sensor is 0.86 N, with a sensitivity mV/(mN mV). The resolution of the sensor in terms of the normalized voltage change corresponding generated strain ratio is denoted as 3.81x10(-5) (V/V), and the minimum detectable strain ratio is 2x10(-5), sensitivity of 2.6926 (V/V)/(Delta L/L). Finally, it is reported that the sensor exhibits a stretchability approximately 33%.