Camera-based force and tactile sensor

Abstract

© Springer International Publishing AG, part of Springer Nature 2018. Tactile information has become a topic of great interest in the design of devices that explore the physical interaction with the external environment. For instance, it is important for a robot hand to perform manipulation tasks, such as grasping and active touching, using tactile sensors mounted on the finger pad to provide feedback information. In this research we present a novel device that obtains both force and tactile information in a single integrated elastomer. The proposed elastomer consists of two parts, one of which is transparent and is wrapped in another translucent one that has eight conical sensing elements underneath. Two parts are merged together via a mould. A CCD camera is mounted at the bottom of the device to record the images of two elastomer mediums illuminated by the LED arrays set inside of the device. The method consists of evaluating the state of the contact surface based on analysis of the image of two elastomers. The external deformation of the elastomer is used to measure three force components Fz, Mx and My. The measurement is based on the area changes of the conical sensing elements under different loads, while the image of the inner transparent elastomer captures the surface pattern, which can used to obtain tactile information.