Experimental testing of a power-assisted space suit glove joint

Utilizing new glove designs in conjunction with state-of-the-art robotics technology, the University of Maryland Space Systems Laboratory and ILC Dover, Inc. have developed a prototype, power-assisted space suit glove joint. Previous results have established the ability of this system to significantly decrease the torques required to extend the joint. The current paper describes additional design refinements and more precisely quantifies the performance of the system by examining range of motion and EMG-derived metrics from human subjects performing a repetitive manual task. The results indicate that power assist significantly decreases the physiological effort required to flex and extend the joint, while at the same time greatly increasing the achievable range of motion. Power assist enables a 440% increase in average range of motion while simultaneously decreasing by 30-40% the effort required to accomplish these motions. Moreover the effects of muscle fatigue are not apparent when the assist mechanism is active, while in unassisted trials fatigue decreases the observed range of motion by more than 40% during the task.