DEVELOPMENT OF KINEMATIC KINETIC PERFORMANCE TOOLS IN SYNTHESIS OF MULTI-DOF MECHANISMS

Kinematic and kinetic performance are important issues in designing mu lti-degree-of-freedom mechanisms such as robotic manipulators. In the engineering design stage, it is especially important that the designer can grasp the characteristics Of the mechanism. The aim of this study is to develop a means of representing the kinematic and kinetic perfo rmance of the mechanism in such a way that the performance characteris tics are quantified analytically and visible graphically to the design er in their entirety at the conceptual design stage. Various performan ce indices are derived from the Jacobian matrix and its quadratic form . These performance indices are the local kinematic cross-coupling ind ex (angle of intersection between column vectors of the Jacobian), the local directional mobility index (ratio of Jacobian's eigenvalues), a nd the local efficiency index (product of Jacobian's eigenvalues). Gra phical images of these performance characteristics using eigen-ellipso id and workspace trajectory contours are introduced. Critical performa nce points in mechanism workspace are identified and elaborated for de sign considerations. Based on the graphical representation of these pe rformance characteristics, design rules for achieving different perfor mance objectives can easily be implemented. This method is applicable to computer-aided design of a mechanism and predetermination of its ki nematic and kinetic performance.