A Sttudy on the Isotropic Measures of 6-DOF Manipulators

• Main Author: 鄭釵銘
• Other Authors: 蔡高岳
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/87448367686212315411

碩士 === 國立臺灣科技大學 === 機械工程系 === 91 === The ratio of the smallest and largest singular values of an orienting (positioning) Jacobian can be used to develop orienting (positioning) isotropic designs or to evaluate the closeness of a configuration to an orienting (positioning) isotropic state. The ratio of a 6x6 Jacobian, however, can not be used for the same purpose because we can not distinguish orienting singular values from positioning singular values after obtaining all the solutions from the characteristic equation. Recently, the so-called isotropy conditions instead of the singular values of J have been used (by most researchers) in the design of 6-DOF isotropic manipulators. But these conditions can not be used to evaluate how close a configuration is to a isotropic state. In fact, so far we still do not have a proper measure that can be used for this purpose. In this thesis, isotropy measures for 6-DOF manipulators are developed using the definition of isotropy or isotropy conditions. A manipulator will attain an isotropic configuration if either of the measures equal to 1. Currently, a manipulator is termed isotropic if it can attain at least one isotropic configuration. The isotropic state at other configurations has not been considered. With the isotropic measures developed in this work, we can use them to evaluate global isotropy (isotropic state at all possible configurations of a manipulator) of all the existing isotropic manipulators to obtain the design with optimum global isotropy.