PUB - Publikationen an der Universität Bielefeld

Dexterous grasping and manipulation of objects with robot hands requires the ability to monitor contact locations in real-time and with good spatial resolution in order to close the control loop required for object and contact trajectory generation. The ability to recognize incipient slippage will allow for autonomous grasp force adaption – a major prerequisite to handle objects of unknown weight. To provide appropriate tactile sensing capabilities, this paper presents the development of a modular tactile sensor system focusing especially on high frame rates (up to 1.9 kHz) and good spatial resolution (5mm). Larger sensor areas are composed from identical sensor modules providing a 16×16 matrix of tactels. We compare different tactel layouts and force-sensitive materials to achieve optimal sensitivity especially to low forces in order to facilitate detection of first touch. Finally we demonstrate the versatility of the sensor to detect incipient slippage employing a Fourier transformation of the high-frequency tactile signal as input to a multi-layer perceptron, which learns to accomplish the classification tasks.