Characteristics evaluation of a pressure sensitive rubber-based tactile sensor

Pressure sensitive rubber has been proposed to be used as the tactile sensor in robotic catheter system for MIS (minimally invasive surgery). The contact area in the blood vessels can not be clearly known within the current technical level. In this paper, supposing there are three different situations when the sensor contacts the blood vessel wall, including the contact area is one point, the contact area is part of the surface and the contact area is entire surface. This paper analyzes the strain based on FEA (finite element analysis) when the force loading area of pressure sensitive rubber is different. The linearity of pressure sensitive rubber is good on condition that the contact area is constant. Then we change the contact area to do more experiments and learn that the strain increases with the increase of the contact area. Keep contact area as a constant value, we can get an accurate calibration curve of pressure sensitive rubber. In this way, we evaluate the characteristics of the pressure sensitive rubber when it is used in robotic catheter system for MIS as a novel tactile sensor.