METHODS FOR REDUCING ENERGY-DISSIPATION IN COSMETIC GLOVES

For cosmetic reasons, hand prostheses are provided with cosmetic glove s. Their pleasing appearance, however, is accompanied by poor mechanic al behavior, resulting in a negative influence on prosthesis operation . Glove stiffness is high and nonlinear, and internal friction in the glove material causes energy dissipation (hysteresis). In this article , two methods for reducing hysteresis in cosmetic gloves are proposed, that may be applied independently or in combination. Glove modificati on. Altering the mechanical properties of the glove itself is the firs t method that is presented. It was found possible to reduce both stiff ness and hysteresis about 50% by forming grooves into the inside of th e glove. Together with the evaluation of this method, several properti es of the cosmetic glove were determined. Motion optimization. Additio nally, a second method for reducing hysteresis was developed. The amou nt of hysteresis is influenced by the way the glove is forced to defor m. The prosthesis mechanism, determining this deformation, was designe d for minimum hysteresis and maximum cosmesis. For the prosthesis-glov e combination used in this study, thumb motion optimization reduced hy steresis by about 65%.