New Electro-Hydraulic Foot Prosthesis.

Motion Control, Inc. (MCI) will complete an electronic-controlled version of the advanced hydraulic foot/ankle which will demonstrate the feasibility of the automatic adjustment of resistance throughout the range of motion. The advanced MCI Foot, especially the automatic controlled version, is expected to contribute to the function of the prosthesis wearer, resulting in advanced and more natural walking benefits. Three objectives will be pursued: ¦Implementation of electric servo-valves into the existing foot-ankle design. Manual valves have been developed at present, and in preliminary testing, shown to be successful at setting the foot wearer’s preference for dorsi-flexion and planter flexion. ¦Development of sensors for ankle position, inclination, temperature, and load will also be developed, for integration into the ankle electronic Controller; sensors must utilize rugged design, for long-term reliable usage in the foot, and small size to fit within the anatomical shape of the foot. ¦• Implementation of an algorithm for ankle control by microprocessor. The automatic control of ankle resistance will depend upon the variable of position, inclination, and load, indicating the point in the gait cycle in which the walker’s step is taken. The temperature will be automatically compensated for as the hydraulic fluid warms and changes viscosity. Success in the function of the auto-controller will be evaluated in-house, in the Foot Testing Center. MCI proposes to perform field trials under a Phase II project.