Topological Structure Coupling-reducing of Parallel Mechanisms

Structure coupling-reducing can reduces the complexity of forward position solutions. But the topic is little being studied so far. This paper studies structure coupling-reducing design methods and novel mechanisms with low coupling-degree. Firstly, a novel concept--structure coupling-reducing is presented. The differences and relationship of the structure coupling-reducing (SCR) and motion decoupling (MD) are clarified and revealed. Then, three SCR methods are proposed, which are method based hybrid branched chains, method based superposing kinematic joints, method based separating negative DOFs respectively. At last, SCR examples are illustrated and some novel mechanisms with low coupling -degree are obtained, which offers good potential applications. These SCR methods can be applied to all complex planar mechanisms and spatial mechanisms. They are of great significance in topological structure optimization, kinematics solution, real-time control and application.