Identify key grasping-related properties based on cutaneous electrotactile stimulation

It is important to close the control loop by providing tactile feedback to prosthesis users. An increasing number of researchers attempt to improve grasping performance by providing various types of tactile feedbacks. In our study, we improve the performance by a virtual environment in which subjects acquire two key grasping-related properties, including object´s stiffness, economically holding power (F_eco) that could stop the objects slipping by a minimum force, using pressure feedback and slipping feedback generated by electrotactile stimulation during they are grasping objects. Results indicate that this method is feasible. The accurate discrimination of two levels´ stiffness is 95.4%, and the accurate discrimination of four levels´ economically holding power (F_eco) is 78.3%. Furthermore, in order to compare the discriminating performance, we investigate the confused types in discriminating the stiffness and the economically holding power (f_eco).