Fem deformation analysis of a transtibial prosthesis fed with gait analysis data. a preliminary step towards restoring proprioception in amputees

The lack of proprioception in patients with lower limb amputation is a major impairment affecting balance and metabolic consumption, and increases the risk of falling of amputees. As of today, several methods have been considered to restore this capacity, mainly involving the use of force sensing resistors and vibrotactile feedback systems. This study explores the possibility to use an elastomeric sensor filled with conductive liquid as a strain sensor to obtain proprioceptive data from the prosthesis during the gait cycle. A FEM simulation was carried out to study the deformation of a transtibial prosthesis, in order to identify the point of maximum deformation for the sensor application. Both the static and the dynamic analyses identify a frontal area in the ankle region with a maximum value of 0.02 m/m, at the intersection of leg and foot. Results are therefore encouraging for the future application of an elastomeric strain sensor in the indicated area.