Kinematic Design of Serial Link Manipulators from Task Specifications

Abstract

The Reconfigurable Modular Manipulator System (RMMS) consists of modular links and joints that can be assembled into many manipulator configurations. This capability allows the RMMS to be rapidly reconfigured to custom tailor it to specific tasks. An important issue related to the RMMS is the determination of the optimal manipulator configuration for a specific task. This article addresses the problem of mapping kinematic task specifications into a kinematic manipulator configuration. For the design of two-degrees-of-freedom (2- DOF) planar manipulators, an analytical solution is derived. Because analytical solutions become impractical for problems with more than two design parameters, we have also developed a numerical approach for the design of 6-DOF manipulators. The numerical procedure determines the Denavit-Hartenberg (D-H) parameters of a nonredundant manipulator with joint limits that can reach a set of specified positions/orientations in an environment that may include parallelepiped-shaped obstacles. Finally, this approach is demonstrated with a three- dimensional example for a 6-DOF manipulator.