Brace design for knee-angle measurement in human gait using infrared sensor

This paper demonstrates a novel design for knee-angle measurement in the sagittal plane. In this study, a wearable knee-brace was fabricated using vacuum moulding technique with an infrared (IR) sensor mounted on the brace. The subtle variations in the knee-angle positions were measured in the form of voltage fluctuations of sensor. These signals were collected during gait cycle and then digitized using 16-bit analog-to-digital conversion unit (BIOPAC Sys). Using mechanical crank system principal, the acquired signals were used to simulate the actual knee-angle points. The overall development is portable and comfortable to wear with minimal hindrance in natural body movements. This device holds promise for utilization in long term monitoring of human gait cycle.