Kinematics, Singularity and Workspace Analysis of a Reconfigurable Parallel Mechanism for Large Scale Assembly

Reconfigurable parallel mechanisms (RPMs) own the advantages of high stiffness., good dynamic performance due to their parallel structural features., and can reconfigure themselves to accommodate different., complicated and changeable task requirements. This paper deals with kinematics of an RPM which can be converted into three operation modes in six motion cases. First., inverse kinematic models of the RPM are established through the method of closed-loop vector. Then Jacobian matrices of the RPM are derived., based on which singularity of the system can be analyzed. Finally., reachable workspace of the RPM is searched by considering corresponding constraint conditions. Results show that workspace of RPM is continuous and there is no empty hole. However., singularities occur in the reachable workspace, which should be avoided in trajectory planning.