An experimental teletaction system for detection and display of human pulse

Teletaction is the sensing of a remote object by transmitting tactile information from a remote tactile sensor to an operator's skin by using tactile interface devices. Tactile interface is used to reproduce the information such as force (static and dynamic), texture, roughness, temperature, and shape. One of the important applications of teletaction is in telesurgey where tactile information such as tissue softness and pulse sensing becomes important parameters. This dissertation describes the design, modeling, simulation, fabrication and testing of an experimental teletaction system to detect and reproduce human pulse. It consists of three major components: pulse sensing system, pulse display system and the data processing system. In the pulse sensing system, the polyvinylidene fluoride (PVDF) probe sensor was designed and fabricated to sense the human pulse signal. In the pulse display system, a real time position and a force feedback control systems were designed to control the linear actuator system which would reproduce the pulse position or force information on the pulse display block. In the data processing system a real time computer control system was built. This system included hardware and software to perform data acquisition, signal processing and control. In addition, the analysis and simulation of the stress and strain matching based on elastic half space model were carried out to ensure the stress and strain matching between the pulse sensing and pulse display. The simulation and the experimental results demonstrated the close matching between the sensed and displayed pulse. A psychophysics test showed that the fingertip feeling at the pulse display end closely matched the feeling of touching human pulse directly.