Instrumented objects for quantitative evaluation of hand grasp.

Two instrumented objects have been developed for quantitative assessment of functional tasks performed with the hand. These objects are useful for assessing neuroprosthetic hand grasp systems, and may also be useful in evaluating a variety of other upper limb disabilities and rehabilitation techniques. One object monitors grasp forced and object orientation during palmar prehension, allowing simulation of a drinking task or of manipulating a book. The second object monitors grasp force during lateral prehension for simulating eating or writing tasks. The two objects provide tools to analyze how a subject uses a hand grasp neuroprosthesis to perform activities of daily living. The objects will also be useful in comparing different methods of controlling the neuroprosthesis and in evaluating future changes in the neuroprosthetic system. Assessment trials with these two instrumented objects were performed quickly in an outpatient clinic setting.