Research On Rolling Control Technology Of Guided Artillery Rocket’s Fixed Canard Rudder

Electromechanical actuator (EMA) is the key actuator for the guidance ammunition trajectory correction process, which used to control the projectile’s flight attitude. And also it takes on a low cost, miniaturization, high precision development trend. The miniaturization EMA and its motion control technology was studied in this thesis, which meeting the urgent needs of small and medium caliber guided artillery rockets. Thus the results can reference for guided artillery rocket’s trajectory correction mechanism technology.The main work and research results are summarized as follows.The fixed canard rudder scheme suitable for small and medium caliber guided artillery rockets was researched. Based on the rolling control technology for fixed canard rudder and the intelligent control technology of permanent magnet brushless dc motor (BLDCM), the structural composition, working principle and performance characteristics of the fixed canard rudder were mainly analyzed in detail, the mathematical model and Matlab/Simulink dynamic simulation model of the rudder were established, So the feasibility of the rudder’s motion control system was verified. Then the single channel rolling control strategy for fixed canard rudder was proposed, in addition, which speed switching forms can get the best cycle average controlling force and moment were analyzed. The controlling force and moment were added to the deduced artillery rocket’s6DOF ballistic equations, and then the trajectory correction ability simulation of fixed canard rudder was done, the law between the side correction force and terminal impacts was analyzed.After all, the feasibility of adopting fixed canard rudder to do the two-dimensional trajectory correction is proved.In order to achieve EMA’s rapid, high precision and robustness control performance, the effective control algorithms were seeked to suppress the system’s internal and external disturbance, mainly studied two control algorithms, one was the off-line optimization algorithm, the other was the real-time online optimization algorithm. Firstly, the off-line optimization algorithm to tune proportional integral derivative (PID) controller’s coefficients was proposed, which based on Error Back Propagation (BP) Artificial neural network (ANN) and genetic algorithm (GA).With this optimization algorithm, the EMA system’s step response performance and bandwidth can be enhanced obviously, and the EMA controller’s parameters can be automatically optimized. Also it is very suitable for nonlinear system and complex and not easy to modeling control system.In addition, a modified ADRC cascade controller suitable for EMA’s motion control was researched, for conventional ADRC controller’s position control is not accuracy, thus the reference acceleration as a feed-forward control was added to ADRC cascade controller, and its control abilities of step response’s rapidity,sinusoidal trajectory tracking, system’s parameter variations and external disturbance rejection and so on were researched all-round.Compared with the PID controller, the proposed modified active disturbance rejection controller can achieve precision trajectory and excellent disturbance rejection performance. Consequently, the high speed and high precision motion control of the EMA was realized.Meanwhile, in order to achieve the security and reliability of the EMA’s control system requirements, a dual mode control method of brushless DC motor (BLDCM) either with position sensor or sensorless was researched. Under the normal state, the EMA was working with the position sensor control method, once the position sensor works abnormal or damage, the controller will automatically and smoothly switch to sensorless control mode, finally the reference experiment were carried out. The feasibility of adopting the dual mode controller with position sensor or sensorless to EMA control was proved, thus it could enhance redundancy of the EMA system.The prototype of the fixed canard rudder was made, and its reference experiments were carried out. The fixed canard rudder only needs a drive motor and a set of control system, which can be designed to standard nose applying on conventional ammunition guidance reform.The trajectory correction system’s scheme for the artillery rocket installed fixed canard rudder was discussed, the composition and working principle of the trajectory correction system were analyzed, and some key technologies such as the missile-bornecomputer, BD/GPS dual-mode integrated navigation unit, geomagnetic attitude detection unit were researched preliminarily. The trajectory correction scheme for the artillery rocket was researched preliminarily through numerical simulation. The characteristics of the trajectory tracking guidance law (TTG) and the proportional navigation guidance law (PNG) were analyzed.The guidance law in the missile-borne computer should supply the azimuth angle for the rudder, so a simple composite guidance law was researched, and the feasibility of the proposed trajectory correction scheme was proved.