In order to design and implement a high-precision Stewart platform to precisely adjust the position and posture of the secondary mirror of a space camera, the following measures were taken: firstly, the inverse mathematical model and ADAMS parametric model of the Stewart platform are established, which are the basis of structural optimization design; secondly, the structural parameters of Stewart platform are obtained through structure optimization design in ADAMS after determining the objective function; thirdly, a 50nm resolution driving strut based on brushless DC motor, ball screw, grating ruler and PI closed-loop control law is designed, which strongly guaranteed the six degrees’ resolution of the Stewart platform that mainly consist of 6 such high-resolution driving struts; finally, the accuracy of Stewart platform is tested via dual frequency laser interferometer and photoelectric autocollimator, and the test results show that the displacement resolution of the Stewart platform is 0.2 μ m, and the angular resolution is 1”, which meets the requirements of the index. The Stewart platform has been successfully applied to the space camera by tuning the secondary mirror precisely in 6 degrees of freedom in the optical alignment experiment, which lays a solid theoretical and practical foundation for on orbit application in future.

In order to develop a high-resolution 6-DOF parallel robot, a method for analysing parallel robot’s position and orientation resolution is proposed, which is based on the same scale scaling and quantifying of struts increment. Firstly, calculating struts increment of the target position and orientation. Secondly, reducing struts increment in the same proportion. Thirdly, quantifying them with the resolution of the strut, and the minimum struts increment and struts length are obtained. Lastly, six single DOF minimum motion increments, namely pose resolution, are obtained after forward kinematic solution. The analysis software is compiled with VC++, and the 6-DOF Stewart parallel robot for the secondary mirror of a high-resolution space camera is designed. The measured results show that the analysis results of pose resolution are basically consistent with the measured values, and the analysis method has strong engineering guiding value.

Position and orientation adjustment of the secondary mirror is one of the effective ways to improve the image quality of space camera. In order to optimize the structural design of a 6-DOF Stewart platform for secondary mirror, simulation method of kinematics and dynamics of parallel manipulator based on virtual prototyping technology was studied. Firstly, the ADAMS parametric model and inverse mathematical model are built. Secondly, theory analysis of inverse kinematics of Stewart platform was performed, and the analytical results of inverse kinematics were obtained by mathematical modeling. Thirdly, simulation of inverse kinematics run in ADAMS after the virtual prototype of parallel manipulator was established. The simulation results in ADAMS and analysis results are consistent, which proved the correctness of the virtual prototype model. Lastly, the kinematics and inverse dynamics simulation were realized by driving each strut using result of inverse kinematics. The analysis method of kinematics and dynamics of parallel manipulator provided a theoretical basis for optimizing design of a Stewart platform.