Ionic flexible capacitive three-dimensional force sensor for electromechanical signal monitoring

Accurate 3-D force sensing technology plays a crucial role in monitoring the electromechanical signals of the manipulator. Despite the design of various flexible capacitive 3-D force sensors, their sensitivity often fails to meet the requirements for monitoring manipulators effectively. To address this issue, this work has designed an ionic flexible capacitive 3-D force sensor with pyramidal microstructure. This sensor relies on the mechanical deformation of the pyramidal microstructure and the coupling of the capacitive effect of the electric double layer to output sensing information. The sensitivity of this sensor can reach 38.3 kPa $^{-{1}}$ , and it has a fast response time (62 ms), excellent hysteresis, and repeatability. With the application of backpropagation neural network (BPNN), the accuracy of decoupling can be optimized, resulting in the error being reduced to $10^{-{3}}$ . The sensors have the ability to monitor electromechanical signals that can help the manipulator identify the topographic features of a target object, as well as monitor the gripping force of the manipulator and whether the target object is sliding. This unique 3-D force sensor provides novel ideas for the design of new multidimensional force sensors, paving the way for the development of human-computer interaction and wearable devices.