Capacitive insole sensor for hip surgery rehabilitation

We are developing a capacitive insole sensor in order to measure the force between foot and an insole. The sensor is intended to guide a hip surgery patient to train the operated leg with a suitable force. In this paper, we propose a flexible, laminated structure for a capacitive force sensor matrix. The preliminary measurements indicate that the sensor could be used as a limit detector to sort out too light and too heavy steps. We have also evaluated our method comparing our sensor signal to the signal measured with a commercial force transducer. Finally, we have made long-term measurements in order to evaluate the stability of the capacitive sensor elements.