A grasp force and position sensor for the quantitative evaluation of neuroprosthetic hand grasp systems

An instrumented grasp sensor has been developed for use in quantitative evaluation of neuroprosthetic hand grasps. This hand-held device monitors both grasp force and grasp opening with the subject utilizing either palmar or lateral prehension, and can be used to quantify the grasping of variable-sized or compliant objects. The grasp sensor provides a quantitative tool to analyze a subject´s hand grasp, thus allowing the neuro-prosthetic system to be tuned for the best performance. It can supply data on how a grasp changes under various conditions, such as different wrist positions. The device can also be used to perform quantitative comparisons for future neuroprosthesis improvements, such as the addition of sensory feedback, closed-loop control systems, and alternative command/control methods. The simultaneous measurement of grasp opening and force could prove useful in applications other than a neuroprosthesis, such as quantifying other hand impairments and studying the physiological control of grasp