Research On The Technique Of Active Damped Control Of Micro-vibration

With the rapid development of new and precise technology, high-fine machine,hyperfme processing and testing get more and more percents, so the request of micro-vibration control becomes higher and higher. Conducting the research on the technique of micro-vibration control is valuable for theoretical sake and practical application.This paper based on passive vibrating isolation system which is supported by air-spring, presents a system using the horizontal active damper to makeup the fault of traditional isolation platforms, which includes three parts, data acquisition and data processing unit, computer control unit and electromagnetic damper unit.First, a data acquisition and data processing unit which is designed according to the properties of microvibration is presented. This unit which includes vibration measurement, signal amplifier, signal filter, A/D (D/A) converter and FFT devices is the premise of whole active system. The data gathered by this unit can be recognized and analyzed in the computer.Second, a universal six-dimentional dynamic model is proposed, which is then simplfied to satisfy practise. Based on this model, a state-space equation is designed, which is the foundation of the computer control.Third, this paper designs a control algorithm and a control law, and schemes a whole set of computer control flow chart. The state-space equation is proved correct by the results of a analyzed project by utilizing SAP2000 and SIMULINK software. A good control effect of this isolation platform with LQG control algorithm has been showed by comparing the results of isolation platform without horizontal active control system to the results with the horizontal active control system. And the results also displayed the influence of different values of weight function.Finally, in order to improve the electromagnet work efficiency, the conducting material and the style of the electromagnetic damper are designed. This paper proposes a new structure of electromagnetic damper to achieve the direction of the output forces controlled only by the magnitude of control current and projects the main step to design such a damper.