A bio-inspired cylindrical tactile sensor for multidirectional pressure detection

In this research, a cylindrical tactile sensor was developed inspired by the anatomy of a tooth. The sensor was made using two rods; one was plugged into the other, just like a tooth that is plugged into alveolar bone. A piezoresistive conductive polymer composite was used to hold the inner rod to the outer rod, as well as to detect pressure application to the sensor. Pressure was applied to the tip and the sides of the sensor device, and at the same time, the resistances from the conductive polymer composite were measured through all the six-pair electrode combinations. When pressure was applied to the tip of the device, the decrease in the ratios of the resistance change can be observed from all six-pair combination of the electrodes. Applying pressure from the side in between two electrodes caused the ratio of resistance change at the compressed side to be decreased, but increased at the tension side. The same pattern can be observed when pressure was applied at the side that has an electrode. The position of the applied pressure can be determined by observing the pattern of resistance change in between all pairs of electrode combinations.