Structural kinematics of 6-revolute-axis robot manipulators

The complexity of the inverse kinematics problem for 6-revolute-axis robots is highly dependent on the mechanical structure of the robot. The study of the kinematics of 6-revolute-axis manipulators, based on results of previous analyses of 4- and 5-axis manipulators, leads to an efficient inverse kinematics method that reduces the problem to solving a system of two nonlinear equations in two variables. We also show that 6R manipulators with at least two intersecting or parallel joint axes can be solved by a faster one-dimensional technique. The numerical techniques are illustrated by computer simulations. (C) 1996 Elsevier Science Ltd.