An Emulator System for Developing Improved Elbow-Prosthesis Designs

A practical technique for the design and evaluation of elbow prostheses has been developed for use in a laboratory environment where resources and manpower are limited. Prospective designs are emulated with a combination of hardware and software as opposed to constructing actual prototypes. The emulator system consists of a high-performance, electrically powered elbow prosthesis worn by an amputee and interfaced to a digital computer. Design changes may be examined simply by reprogramming the dynamic behavior of the emulator rather than by reconstructing hardware. Changing the inherent emulator dynamics to desired dynamics is achieved with a digitally supervised, analog control circuit that is more robust than a purely digital controller. The system can emulate existing powered elbow prostheses and some important characteristics of the intact elbow.