An Active Foot-Ankle Prosthesis With Biomechanical Energy Regeneration

TLDR

The study develops a design methodology for a regenerative transtibial prosthesis by modeling and optimizing motor, spring, gearbox, and transmission combinations to minimize power and energy consumption. A robust robotic transtibial prosthesis with regenerative kinetics was built and evaluated in a 6‑month trial on a below‑the‑knee amputee, using quasistatic system modeling, DC motor and transmission analyses, and an optimization framework. Model predictions of power and energy closely matched measured data, validating the approach, and the kinetic minimization enabled a self‑portable actuation system and battery.

Abstract

A unique, robust, robotic transtibial prosthesis with regenerative kinetics was successfully built and a 6-month human subject trial was conducted on one male below-the-knee amputee under linear walking conditions. This paper presents the quasistatic system modeling, DC motor and transmission modeling and analyses, design methodology, and model verification. It also outlines an approach to the design and development of a robotic transtibial prosthesis. The test data will show that the true power and energy requirement predicted in the modeling and analyses is in good agreement with the measured data, verifying that the approach satisfactorily captures the physical system. The modeling and analyses in this paper describes a process to determine an optimal combination of motors, springs, gearboxes, and rotary to linear transmissions to significantly minimize the power and energy consumption. This kinetic minimization allows the downsizing of the actuation system and the battery required for daily use to a self-portable level.