Tactile sensing fingers device using quantum tunneling composite (QTC) pills / Nurizzah Lina Azaman

This study investigated the potential of new material namely Quantum Tunneling Composite (QTC) pills as a tactile sensor. The properties and potential of QTC pill motivate this study. The purposed of this study is to develop a new tactile finger device to increase muscle strength and functional ability of the hands. This is due to the health problems involving the hand such as due to stroke, Parkinson, and carpal tunnel syndrome. These problems cause difficulties for hand to remain stable when grasping objects. In this research, three main objectives were highlighted. The first objective is to characterize the nature of QTC pill as a tactile sensing application. The second objective is to design and develop a tactile finger device using QTC pills for tactile sensor application and the third objective is to evaluate the performance of QTC pill as tactile sensing for the device. There are only two parameters which were considered in developing tactile finger device. These parameters are force and different shapes of the object. The piezoresistive experimental test was performed to determine material resistivity characteristics. Then, grasping and gripping experiments were carried out to evaluate the suitability of QTC pill as a tactile sensor for the fingertip device. The results showed the unique electrical behavior occurred when the graph of force vs. resistance was plotted and the exponential curve was obtained. In no compression, the QTC pill act as an insulator but in the highest compression, it acts as a conductor. This is due to no electron can pass through this material without compression. This proved that QTC pill has very high resistivity. Then, the result was supported by graph current vs. voltage. At very low voltage, the electrons exhibit very little energy to tunnel through the insulating material barrier. In addition, the Concept 3 was chosen as a prototype tactile finger device. Then, the prototype used to evaluate the three types of different gripping touches which are; no gripping touch, light gripping touch, and a heavy gripping touch of objects. The data obtained show that the sensitivity of the tactile sensor varies from the range as small as 0.098N. This is inline with the theory that the higher the resistant, the more difficult for the electron to flow in QTC pill. As the final analysis of data was displayed on Lab VIEW, the experiment of heavy touch shows the highest data as 7.123N. This data is obtained by index finger interaction between the shapes of pyramid object. The overall data collected has proven that the value of QTC sensor will increase if the amount of the force gripping is increased. As a conclusion, it can be said the QTC Pills are suitable tactile sensor for developing fingers device. Furthermore, in future, it can be applied in medical technology to help the weakness hand patients to improve their quality of life.