Characteristics of optical silicone tactile sensor

Abstract

The main objective of this research work is to analyze the characteristics of a newly developed optical tactile sensor for sensing surface hardness. Many optical tactile sensors are bulky in size and lack of dexterity for biomedical applications. Therefore, this tactile sensor is design relative small in size and lexible for easier insertion in endoscopic surgery application. The characteristics of the tactile sensor are calibrated with respect to changes in the diameter, area and perimeter of a silicon tactile sensor subjected to normal forces applied at the point of interaction. A surface exploration computer algorithm to obtain the sensing information was developed to analyse the characteristic of the optical tactile sensor. The overall image analysis technique involves the following main stages: image acquisition (capturing of images), processing (thresholding, noise iltering and boundary detection) and evaluation (force measurement). The measured forces were then compared to the actual forces to determine the accuracy of the tactile sensor’s characteristics. The results showed that the sensing characteristic with respect to changes in perimeter of the tactile sensor is more accurate compared to the other sensing characteristics. The outcomes of this research shows that the functionality of the developed new image analysis computer algorithm coupled with the silicone tactile sensor is suitable for biomedical applications such as in endoscopic surgery for measurement of tissue softness.