Preliminary evaluation of the tactile feedback system based on artificial skin and electrotactile stimulation.

This research is motivated by the need of integrating cutaneous sensing into a prosthetic device, enabling a bidirectional communication between the amputee and the prosthetic limb. An electronic skin based on piezoelectric polymer sensors transduces mechanical contact into electrical response which is conveyed to the human subject by electrotactile stimulation. Rectangular electrode arrays are placed on each patient's forearm and experiments are conducted on five different subjects to determine how well the orientation, position and direction of single lines are recognized. Overall, subjects discriminate the different touch modalities with acceptable success rates. In particular, the direction is identified at best and longitudinal lines on the patient's skin are recognized with the highest success rates. These preliminary results assess the feasibility of the artificial skin - electrostimulation system for prosthetic applications.

A novel technology for motion capture using passive UHF RFID tags.

Although there are several existing methods for human motion capture, they all have important limitations and hence there is the need to explore fundamentally new approaches. Here, we present a method based on a radio frequency identification (RFID) system with passive ultra high frequency (UHF) tags placed on the body segments whose kinematics is to be captured. Dual polarized antennas are used to estimate the inclination of each tag based on the polarization of the tag responses. The method has been validated experimentally for the shank and thigh in the sagittal plane during treadmill walking. The reference segment angles for the validation were obtained by an optoelectronic system. Although the method is in its initial phase of development, the results of the validation are promising and show that the movement information can be extracted from the RFID response signals.