Research On The Control System Of Inertially Stabilized Platform Gimbal For Airborne Remote Sensing

In order to realize the high resolution of earth observation,it is urgent to develop a high performance inertially stabilized platform using for airborne remote sensing in China.In this paper,based on the inertially stabilized platform prototype,the research of gimbal control system is studied in detail.Firstly,the dynamics model of three-axles gimbals and disturbance model are built up,the evaluation performance index is put forward,the dual-loop control loop is established.Then,the controller is designed after using the PID method.Finally,the good performance of the controller is verified by simulation and practice.To further improve the control precision,the limit equation and target function are obtained after analyzing,from frequency domain,the disturbance and considering both Nyquist stability and interference suppression performance,which transforms the problem of controller design into multi-objective optimal problem.Then,the controller design is completed by using genetic algorithm.Finally,the result from simulation and practice proves that the method is useful and can be implement to the engineering.Combine with the digital control system character,the difficult issue of LuGre friction parameter identification is studied.A novel identification method,which implements firstly limiting the range of parameters'value by formula derivation and analysis and then applying genetic algorithm to accomplish exact identification,is put forward.Finally,the friction compensation simulation and practice are done,whose result showed the validity and practical value of the novel identification method.The subject of gimbal control system design using robust method is studied,considering the alternation of moment of inertia of gimbal system.After analyzing the angle velocity loop,changing the control structure,designing the H_?target function,the controller design is completed applying the robust controller design method.Finally the contrast simulation with optimal controller is done,and whose result shows that the robust controller has not only good stability and anti-disturbance performance,but can keep the performance when the moment of inertia of gimbal is changing.