Improved Intermediate Size Body-Powered Hand

WILLIAM LEMBECK, PE


The objective was to provide a more cosmetically pleasing hand with more natural finger movement than available in commercial hands. An attempt was also made to increase the ratio of pinch force to cable pull, approaching that of the highly efficient standard hook terminal device.

To attain these objectives, three new developments are employed. More anthropomorphic thumb motion is accomplished by pivoting the thumb in a plane that is set at a complex angle to the sagittal plane. Motion is transmitted to the thumb through a simple space crank. Appearance is improved by using a molded, soft urethane rubber interface beneath a specially developed silicone rubber glove. Higher mechanical efficiency has been obtained by rigorous kinematic analysis using computer aided design techniques. The initial design and development phase of the project has been completed recently. One prototype model is undergoing laboratory evaluation.

New York University Post-Graduate Medical School, 317 East 34th Street, New York, NY 10016