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Abstract: Numerical methods for the haptic presentation of contact: Theory, simulations, and experiments

Numerical methods for the haptic presentation of contact: Theory, simulations, and experiments

Ellis, R. E.
Sarkar, N.
Jenkins, M., A.

Proceedings of the ASME Dynamic Systems and Control Division, DSC-Vol. 58, pp. 413-420, 1996

© 1996 ASME. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale, or to reuse any copyrighted component of this work in other works must be obtained from the American Society of Mechanical Engineers.

Abstract:

An important problem in the field of haptic display devices and telerobotics is poor force reflection of contact, particularly of contact with stiff surfaces. There are numerous possible sources of poor performance, including poor contact models, sampling errors, and delays due to computation or data transmission. In this paper we examine effects due to sample-and-hold, which is a fundamental property of both the discrete domain and also of the sensors and power amplifiers used in a haptic-interface system.

We propose that the sample-and-hold concept be generalized to sample-estimate-hold. We show why ordinary zero-order hold generates an active contact interface, and provide ways of improving the feeling of the interface. We have developed a suite of numerical methods for improving the performance of haptic presentation of surfaces. We have conducted both simulations and experiments to demonstrate the efficacy of the proposed scheme. Our contributions are a new method of digitally processing force data, and a systematic method for coupling force-processing systems that run at different rates.

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