Pneumatic actuator inserts for interface pressure mapping and fit improvement in lower extremity prosthetics

The fit of a prosthetic socket to a residual limb is critical as poor socket fit is one of the leading causes of improper function, discomfort, and skin breakdown. The daily and long term volume fluctuation of a residual limb presents a major challenge to maintaining fit. This work presents the initial efforts to develop adjustable inserts that consisted of arrays of small, sensorized inflatable pressure actuators that can expand based on the volume change. We have fabricated and tested actuator inserts to demonstrate their capability for pressure mapping in a limb-socket interface. We have also shown that the actuators have the capacity to maintain positive displacement under load to accommodate for volume change in a residual limb for improved fit.