Tactile and Slip Sensation Acquisition in Prosthetic Hands and Proprioceptive Feedback of Perception for Arm Amputees

Prosthetic hands are expected by upper-limb amputees as useful tools to restore lost hand abilities. Possible real-time and intuitive perception of touching and slipping through prosthetic hands would help amputees a lot in daily activities. In this review paper, the results of several surveys on user demands were firstly summarized, indicating the importance of tactile and slip perception feedback for prosthesis users. A possible way to build artificial sensation in prosthetic hands is to develop one or more sensor systems that can detect sensation signals of, for example, touching and/or slipping. In the second part of this paper, different sensing techniques for tactile and slip signal acquisition, which were especially investigated for the application in prosthetic hands, were reviewed. To transfer the sensor-detected sensation signals into users’ nerve systems is very critical to realize a proprioceptive feedback of perception for amputees. The final part of the paper introduced some possible perception feedback modalities. Stimulations on residual limb surface, such as vibration, temperature, and pressure, are low-cost and easy to realize, but usually considered as distracting and still unintuitive. A direct neural interface may provide intuitive and accurate perception feedback. Electrical stimulations of both somatosensory cortex and peripheral never are possible approaches to regenerate perception feedback for limb amputees. But more research work and clinical verification should be performed before an actual application.