Sliding Mode Variable Tructure Control For Separating-Mirror System And Inhibit Chattering

The separation-mirror servo system is an important component of the infrared target/disturbance simulator. The infrared target/disturbance simulator can accurate simulate for catching target capacity, tracking object power, anti-jamming capability and some dynamic performances of infrared homing head in laboratory. The rotation of the separating-mirror can cause the separation of the target ray path and the disturbance ray path, consequently to provide the infrared target source and the disturbance signal for infrared homing head. But the separating-mirror servo system is exposed to the great disturbance because of its own eccentricity and the external friction influence. Therefore, it has vital significance to control the separating-mirror servo system to stably operate for the guarantee simulation precision of the entire infrared guidance simulation system and the fidelity of the experimental results.In this research, the linear control theory and the sliding mode variable structure control theory are used to design controller for the disturbance in separating-mirror servo system and to carry on the experiment and the simulation research. For chattering phenomenon which in variable structure control system with sliding mode used linear continuous pseudo-sliding mode (LCPSM) control method to inhibit chattering and simulation results are given.Firstly, on the basis of referring to lots of foreign and domestic references, this paper introduces the basic theories and items, summarizes the development process and the technical achievement of the domestic and foreign infrared guidance hardware-in-the-loop simulation technique. Introduces the history,the research direction and the research current situation of the variable structure control theory. Summarized domestic and foreign research results on inhibition chattering.Secondly, elaborate structure and the performance index of the separating-mirror servo system and each key element's selection of separating-mirror servo system and each parameter. mathematical model of the separating-mirror is constructed by the mechanism analysis method. Then, used the classical linear control theory are applied to adjust design the separating-mirror servo system. Through the test experiment and the simulation, the results show that the design can satisfy the criteria.Then, this paper detailed research variable structure control with sliding mode method for the separating-mirror servo system. First introduced variable structure control the basic principle as well as the basic concept, using the pole assignment and the exponential reaching law method to design the sliding mode variable structure controller. By exponential reaching law and saturation function combined method to reduce the chattering of the sliding mode variable structure controller. The simulation result indicated that the variable structure control with sliding method enables the separating-mirror servo system to have more accurate tracking performance and more robust to the system parameter variation.At last, using linear continuous pseudo-sliding mode control method to inhibit chattering in the variable structure system, the simulation result indicated that the linear continuous pseudo-sliding mode control method can be effectively suppress or eliminates chattering phenomenon of the variable structure control with sliding mode. Performance of the separating-mirror servo system is improved much more.