Toward 3D Printed Prosthetic Hands that Can Satisfy Psychosocial Needs: Grasping Force Comparisons Between a Prosthetic Hand and Human Hands

The advancement in 3D printing technologies appears to be the key toward affordable and functional artificial limbs. The loss of an amputee’s capability to do functional tasks like grasping objects has an obvious effect on that individual’s psychosocial behavior. In this paper, we investigate whether a low-cost 3D printed prosthetic hand can perform basic grasping tasks. We determine whether the fingertip forces used in grasping various objects are comparable to the grasping forces applied by the hands of 5 research participants. We considered 5 different grasps, namely, lateral pinch, spherical, disk, medium wrap, and thumb-index finger grasps for both the prosthetic and human hands. For each grasp, 25 readings for each finger were considered in the analysis. Results show that there were significant differences in the grasping contact forces recorded on the fingers of the prosthetic hand and the human hands. Since this prosthetic hand and similar 3D printed hands may not be able to reach the grasping forces of human hands, the results of this work open the motivation for addressing other requirements of articulated artificial hands for social interactions and gestures.