Control, Optimization And Experiment Of The Feed Tracking System For Large Radio Telescope

In this dissertation, considering the special character tics for the next generationlarge radio telescope (LT), active control of cable-cabin system, dynamical andoptimal analysis, dynamical couple between the coarse subsystem and the fine tuningsubsystem, and compound control are studied. In the follows, the main research workscan be described as.1, Considering the special characteristics of the large flexible of long-cablestructures, various structures, and the strong coupling among cables with multiple inputmultiple output (MIMO), control model first is developed. Then, a recursively algorithmof MIMO matrix between input cable and out cable is deduced. In addition,one-step-ahead adaptive control methodology with neural network of nonlinear systemsis presented. Finally, practical LT 50m-model experiment is executed to demonstrate thefeasibility and validity of the methodology.2, Based on Newton-Euler method a dynamic model for the cabin is built, sincemainly inertia of cable-cabin system is concentrated on the cabin. Model error includingwind is considered as an unknown disturbance to the cabin. An reject disturbance slidemode controller is proposed with high robust and MIMO and the forces of the cables isget based non-stationary model.3, Due to analytic solves of the complex dynamic model can not be obtain,integrated optimal design of structure and control system is very difficult using thesensitivities. Considering the problem, a method is developed based on buildingcontroller. The sensitivity analysis of the complex system is transformed into thesensitivity analysis of the linear system. The process of the simultaneous optimizationof control and structural for the Stewart platform is introduced to demonstrate thevalidity of the method.4, The dynamic model of the Stewart platform is presented with the flexiblesupporting based on the principle of Newton-Euler. An integrated dynamic analysis ofthe cable-cabin subsystem and the fine tuning Stewart platform and dynamic couplingbetween the two subsystems is studied. The effecting of the cabin-vibration on differentmasses of moving platform is discussed using H∞theory.5,Considering the special characteristic of the delay of long-cable structure , akinematical model of measurement-point is built to obtain exact states values ofmeasure points involves displacement, velocity, acceleration based on H∞filter theory.The comparison dates between LT50m experiment shows the measurement model isvalidity. A controller of the Stewart platform is presented with the flexible supporting.The simulation results shows that the effecting of the cabin vibration on trackingprecision of the Stewart platform is restrained effectively.