Design And Control Of Electric Actuator In 4R Space Agency

Electromechanical actuator is the key component of the guidance ammunition, its performance affects the accuracy of the projectile attacking directly. On the basis of comprehending domestic and international research status, as the background of 120mm mortar bombs, based on 4R spatial mechanism, the electromechanical actuator system with the 4R spatial mechanism was designed in this paper, the feasibility of the scheme was verified through theoretical and simulation analysis.Firstly, the 4R spatial mechanism was designed as the working mechanism of the actuator, the kinematical parameter was theoretically calculated, the deployable mechanism of folding wings was projected, and the overall scheme design of the actuator system was completed. Then, the kinematic and dynamic characteristics of 4R working mechanism and deployable mechanism of folding wings were derived through the kinematic and dynamic simulation analysis of multi-rigid body in ADAMS, the structure of the electromechanical actuator was finally determined; the more accurate rotation relationship and load conditions of the actuator were obtained through the analysis of the simulation of rigid-flexible coupling. Next, in order to investigate the overload resistance of the electromechanical actuator, the launching over-loading of the actuator system was pre-analysised in ANSYS. The finite element simulation and analysis showed that the optimized structure of the actuator can meet the requirements of 10000g launching over-loading; at the same time, the modal characteristics of the actuator were obtained by the modal analysis in the pre-stress situation. Finally, the electromechanical actuator control system was designed based on the theory of brushless DC motor with Hall sensor. The parameters of the double-closed loop control system of the motor were simulated and optimized in MATLAB/Simulink, also the hardware circuit and control procedures of the actuator system were designed based on TMS320F2812 chip.Theoretical analysis and simulation results show that the electromechanical actuator with the 4R spatial mechanism has the advantages of simple structure, reliable movement, strong ability of resisting overload and so on, which is suitable for two-dimensional trajectory correction in simple guidance ammunition.