케이블 진동 측정을 통한 실시간 케이블 장력 추정

Abstract

In cable driven robot, measurement of cable tension is necessary to ensure system stability and control of position and attitude of platform driven by cables. However direct measurement of cable tension is not only difficult but also inaccurate because of disturbances such as friction and inertia of pulleys, etc. In this paper, an indirect real time tension estimation of cable was addressed. In this algorithm, cable tension is calculated from estimated vibration frequency of cable. To track fast changing nature of vibration frequency of cable during robot operation, the estimation algorithm bases on least mean square (LMS) method. The conditions for convergence of the LMS algorithm are derived and the directional convergence properties were discussed from a new geometric vector analysis. The feasibility of the proposed algorithm was verified along with some computer simulations.