Stiffness influence atlases of a novel flexure hinge-based parallel mechanism with large workspace

Parallel-structure flexure mechanisms are increasingly designed due to their superior characteristics. This paper explores a novel six degree-of-freedom large workspace flexure parallel mechanism based on the concept of wide-range flexure hinge, which can attain sub-micron scale accuracy over cubic centimeter motion range. The geometric dimensions of the flexure hinges utilized in this mechanism as passive joints will influence the system stiffness directly and other properties indirectly such as the workspace, load-carrying capacity, and driving-load capacity etc. In this paper, the stiffness model of individual flexure hinge is established firstly, and then the stiffness of the whole flexure mechanism is modeled via assembling stiffness matrices and formulating constraint equations. Based on the system stiffness model of the whole mechanism, the stiffness atlases´ analysis is presented which provides theoretical principles for designing and developing this kind of flexure parallel mechanism in further. Finally, a 6-PSS large workspace flexure parallel mechanism prototype is proposed according to the analysis results, which will be utilized in the precision positioning.