Control Research Of A Tabletop Active Vibration Isolator Based On The PID Algorithm

In the current social development process, the effect of tiny vibration to the precise instrument operation cannot be ignored. The vibration control and vibration isolation technology is getting more and more attention of the people. A kind of vibration isolation technology does not need additional energy, called passive vibration isolation. But because of its structure characteristics, the low frequency vibration cannot be isolated. Another kind of vibration isolation technology needs extra energy, called active vibration isolation. It can isolate the low-frequency vibration. Hybrid vibration isolation combines passive vibration isolation system with active control components. It makes the isolation frequency band width and also reduces the energy consumption. Thus it will become the focus in the vibration isolation technology field.The structures of vibration isolation system are diverse. The tabletop active vibration isolator is a typical hybrid vibration isolation system. Because of its good stability, wide vibration isolation frequency band and varied passive vibration isolation units, measuring elements, and actuators, it has been widely used.Tabletop active vibration isolation system is not only a kind of passive hybrid vibration isolation system, and it is composed of multiple vibration isolation units combined isolation system, and it can be 6 degrees of freedom vibration isolation. Therefore, to establish its dynamic model to simulation study and experimental study has important significance. In the process of establishing dynamics equations of combined system, the stiffness matrix and damping matrix, mass matrix are important parameters, especially in the research of loading and load center offsets, mass matrix of access is very important. Dynamic equations of system must be able to guide the establishment of simulation model. 6 degree of freedom simulation model of tabletop active vibration isolator to verify the effectiveness of the combined system dynamics equation is meaningful, also to establish the mathematical model provides a more accurate method for subsequent. In the design of control algorithm, PID control algorithm is suitable for unable to get the accurate mathematical model of controlled object, thus the PID control algorithm is used in tabletop active vibration isolation. Through experimental verification, the theory is used in the process of the transitionBased on the analysis of passive vibration isolation and active vibration isolation control methods and control strategies, the dynamic equations and simulation model of six degrees of freedom active vibration isolation system is established, and then this paper analyzes the quality of load and load center of mass migration. In this paper the feed-forward and feedback control strategy and the PID control algorithm are applied to the simulation model and experimental system. Then this paper carries out active control experiment on the tabletop active vibration isolator system, and reveals the different control strategy and controlled parameters on the effect of the active vibration isolation. Based on the tabletop vibration isolator, PID control algorithm and the design of active vibration isolation control experiment system, we get the best performance of vibration isolation of three directions. The starting vibration isolation frequencies are all 1.5 Hz and vibration signal can be respectively attenuated-20 dB and-30 dB. The results point out the direction of the active vibration isolator for our further study on the tabletop active vibration isolator.