A Novel Macro/Micro Dual Driven Flexible Parallel Manipulator for Precision Positioning

摘要

Parallel manipulators as precision positioning devices have been hot issues in the precision operation engineering field. However, it is inevitable that there exist problems of backlash and friction in the conventional hinges used as passive joints in the parallel manipulators. But the adoption of the flexible hinges instead of conventional joints reduces the workspace sharply, although eliminating the backlash. This paper introduces the concept of the long travel range flexible hinges, which provide long travel range in the case of eliminating the backlash. The macro/micro dual parallel manipulator system utilizing this kind of hinges can obtain the nanometer scale resolution within the cubic centimeter scale workspace, which adopts piezoceramic motors and piezoelectric ceramics as macro and micro actuators respectively. The paper presents the operation principle of this dual system integrating 6-PSS and 6-SPS structures. Then the stiffness model of the long travel range flexible hinges is introduced, and the kinematics model is analyzed based on geometric nonlinear solution. And finally the configuration of the control system is presented.