Miniaturized and Modularized Wearable Force Sensing System for Functionality Expansion on Existing Robots

ABSTRACT This work aimed to create a capacitive force sensing system based on flexible materials and structures, miniaturizing the hardware by 87% and the interface, and improving the stability of the signal processing module (from force to capacitance) for robot applications in a wearable shape. The system includes a force sensor, signal acquisition integrated circuit (IC), microcontroller unit, Bluetooth IC, and lithium‐polymer battery. The sensor was composed of polymeric materials and elastomers, which were connected to the wristwatch‐shaped transmission port before the signal was wirelessly analyze in real‐time. Field tests indicated that the responses exhibited reasonable tolerance (less than 2%), reliable short‐ and long‐term stability (variation less than 5%), and remarkable repeatability (linear coefficient of determination of 0.9975). The wristwatch‐shaped transmission port thus demonstrated its superiority in practical application and exhibited novelty from the viewpoint of modularization, with balanced characteristics among similar solutions, which provided add‐on functions to existing robots.