Compliant Parallel Robots - Development and Performance

In this paper the development of a macro parallel robot is presented in which conventional bearings are replaced by pseudo-elastic flexure hinges. The robot consists of a spatial parallel structure with three translational degrees of freedom and is driven by three linear direct drives. The structure has been optimized with respect to workspace and transmission ratio. Additionally, in simulations with the FEA tool ANSYS different geometrical arrangements and combinations of flexure hinges have been investigated with respect to the dynamic behavior of the compliant mechanism. Due to the symmetrical character of the structure and the optimized design of the combined flexure hinges the structure is very stiff. The experimental measured repeatability of the compliant robot is below 0.3 µrn.