Optimum Motion Planning for Tendon-Based Stewart Platforms

摘要

This paper presents the optimal motion planning in Cartesian space for tendon-based Stewart platforms, which are directly driven by n+1 parallel tendons in an n-dimensional space. The optimum motion planning consists of an optimum path planning and trajectory planning with an optimal tension distribution. At first, the workspace conditions of tendon-based Stewart platforms, which incorporate kinematic constraints, dynamic constraints and limiting torque constraints of actuators, are presented. Then, based on the developed workspace conditions, an approach for optimum path and trajectory planning of tendon-based Stewart platforms using minimum-time criterion is provided. As a global optimization strategy simulated annealing integrated together with the local optimization method Powell algorithm is used in this approach. Moreover, the analytical solution of optimal tension distribution is obtained by the developed workspace conditions. Finally, the effectiveness of the method is demonstrated by a three D.O.F Stewart platform driven by four tendons.