Wearable Devices for Remote Physical Rehabilitation Using a Fabry-Perot Optical Fiber Sensor: Ankle Joint Kinematic

The continuous advances in sensing and telecommunications fields have boosted the development of new technologies towards the improvement of healthcare systems. This drive of knowledge is required to address the rise of life expectancy of an ageing population with increased associated physical impairments, in order to ease the burden on already stressed healthcare systems. Towards such objective, this paper explores the use of a wearable optical fiber based solution for the ankle plantar-dorsi-flexion monitoring, to be used in the evaluation of the progress of physical rehabilitation therapies. The proposed device is a non-invasive, small size and easy to use solution, based on a cost-effective in-line Fabry-Perot interferometer, complemented with new dynamic interrogation techniques that allow the angular monitoring of the ankle-shank joint during gait (walking). The designed and produced wearable solution was calibrated and tested in a laboratory environment, with promising results that prove the accuracy of the wearable device, as it falls within the expected pattern of an ankle plantar-dorsi-flexion movement during gait. The developed system can be used for rehabilitation therapies monitoring, to be integrated in exoskeletons or applied for athletes' performance analysis and optimization, during injury recovery.