Application Research Of Active Disturbance Rejection Control Technique In Lensbarrel Control System Of Aerial Cameras

In order to improve control performance of aerial cameras and then improve the total performance, Active Disturbance Rejection Control (ADRC) is applied into aerial cameras for the first time. The control plant of the dissertation is the lensbarrel of an aerial camera. The research on ADRC technique is from three aspects of theoretical analysis, numerical simulation and application. ADRC is applied in speed control and position control of the lensbarrel successfully.The simulation model and mathematical model are given firstly. The theory of TD is discussed and proved effective in transient design and filtering. Through analysis of two kinds of nonlinear control law, LPD, NLPD, TOFC controllers is designed and the advantage of nonlinear control is proved in precision and ability of disturbance rejection.The theory of ESO is discussed and the general format of three order LESO and NLESO. LESO of a single parameter is designed with method of bandwidth parameterization. The order of ADRC and ESO is discussed and control ability of the second order ADRC is demonstrated to the first and third plants.Different ADRC is given based on linear or nonlinear control law, LESO or NLESO. Simulation results prove the high performance and robustness. ADRC achieves zero steady state error without integration and enhances the ability of steady state error rejection. The general procedure of ADRC is presented and analysis of the important parameters is given.A digital controller is designed and speed control is achieved with precision of 0.4% when reference input is 1°/s. The result proves the excellent performance of ADRC as a general controller. The modified TD is presented for transient profile design of speed control to eliminate the dummy dead zone effect of general TD. The angular velocity disturbance is simulated by way of programming.Position control of lensbarrel is achieved with precision of photoelectric encoder resolution. The method of transient profile design with a variable parameter based on multipoint tests and least squares is presented which can achieve global positioning rapidly without overshoot. The disturbance rejection performance of ADRC in position state is confirmed by periodic torque disturbance generated by other motion plant and manual disturbance separately.The work of the dissertation indicates that ADRC can attain and even exceed the control performance of traditional controller. A new thought is presented for design of aerial camera control systems.