The Study Of Vibration Control Parallel System Included Model And Semi-active Variable Stiffness Control Based On PMA

Isolation technology plays an important role in the field of vibration research, and also has a wide use in daily life and industrial production. With the rapid development of science and technology, to improve the accuracy and better equipment to protect equipment and provide technical support, making precision isolation to become one of the main directions of the future development of vibration isolation technology. Therefore, the research of new technologies and new methods, which is suitable for vibration isolation platform, has essential theoretical and practical significance to vibration control. In the vibration control of equipment, semi-active control has the advantages that its effect close to the active control and only requires very little external energy, that make it the major trends in the future about vibration control. Semi-active variable stiffness control increasingly becomes a hot topic in the current control field. This paper uses a pneumatic muscle actuator(PMA) with nonlinear stiffness characteristics as the damping device, that changes the stiffness characteristics of vibration isolation system, it not only avoids system resonance, but provides convenient conditions to semi-active variable stiffness control studies. The main contents are as follows:1 Combining with realistic mathematical model of pneumatic muscle actuator and thinking of the influences include elastic force constraint of the rubber tube and internal friction, the accurate output force model of PMA can be built; Nonlinear mathematical model of pneumatic muscle’s stiffness, internal pressure and damping is deduced by generalized stiffness method and equivalent damping principles, and stiffness and damping characteristics of PMA have been simulated, that provide a theoretical basis for experiment of vibration control parallel system.2 According to flow characteristics of electric pressure proportional valve and gas charging and discharging characteristics of PMA, vibration control system based on PMA can been regarded as pneumatic driven system, and its mathematical modeling also can been built. Experimental platform of vibration isolation system is built and its characteristic is analyzed through static rigidity and shock isolation experiments.3 Based on controllability, strong nonlinear, and multi-coupled output chara cteristics of PMA, doing research for fuzzy PID control strategy. Otherwise, co mbining with the mathematical model of vibration control system which is simulated in Matlab Simulink software environment, making the analysis of compari ng passive vibration isolation control, semi-active and active control of vibration isolation system about effect, scope and characteristic, a good foundation is fini shed for study of vibration isolation system.4 Control system for vibration isolation platform is built, semi-active variable stiffness PID control procedures, which is based on Labview software, has been written, semi-active and variable stiffness control is achieved and its feasibility is demonstrated, all that lay the foundation for optimizing semi-active vibration control system.