Measurement of joint angle for physical therapy using a wearable

Abstract

This work presents the simulation and analysis of the circuit designed to capture angle of elevation of joint of index finger using flexible Multi walled Carbon Nano Tubes (MWCNT) / silicone vulcanized rubber composite. To determine the location of optimum strain on index finger, a 3-D model of the index finger is created using CAD tool. For joint angle measurement, an electronic circuit comprises of wheatstone bridge, microcontroller and LCD is designed using Proteus software. One arm of the Wheatstone bridge is replaced with wearable sensor and rest is fixed resistors. Simulation result shows that the resistance of sensor varies linearly with the joint angle of index finger. Joint angle measurement upto 60° is displayed on LCD. This work will be used to model a wearable human motion monitoring device, which will assist the physiotherapists in observing the angle of movement of joints, thereby, aiding rehabilitative health.