The horizontal or X-Y tracking gimbal of photoelectric system has spatial blind region because of themselves framework limit, In order to solve the problem of blind region and also track object with high-precision and speediness, a new three-axis photoelectric theodolite system with collimation axis eccentricity is brought forward, It can achieve large-scale space tracking by means of mutual conversion of tracking modes.
There is dynamics and inertia coupling in the three-axis photoelectric tracking system, the kind of coupling will directly affect the static state, dynamic state characteristics and indeed system stability. To get high performance photoelectric tracking system, dynamics coupling must be took into account in three-axis photoelectric tracking system. The matrix transformation of angle velocity and moment can be derived from the reference frame relation of three-axis photoelectric tracking system with collimation axis eccentricity; the kinematics property is analyzed by momentum theorem and angular momentum theorem. Through the analysis of inertia coupling in axes, their object differential equation is gained. In the last, the system nonlinear coupling dynamics model is built using multi-body system theory and Lagrange-Eula equation. From the analysis of dynamic equation, it is evident that the photoelectric tracking system with three input and three output contain complicated nonlinear coupling factor, the study of decoupling control must be carried through in order to get high-precision control system. By importing the geometry coordinate transformation, dynamic compensation and nonlinear state feedback, the nonlinear factor can get accurate elimination on base of the system reversibility of input and output, the three-axis photoelectric tracking system control differential equation can be got nonlinear decoupling by static state feedback, several variable photoelectric tracking system turn into three respective self-governed singularity input and output control system to achieve state or output tracking control.
The coupling and decoupling control system is respectively simulated using MATLAB's simulink toolbox. Simulation results have proved that the decoupling control method proposed and the decoupling controller designed for system are effective.