以快速開關閥實現四軸主動式氣壓減振系統控制之研究

Abstract

本文旨在發展四軸主動式氣壓減振系統控制之研究，以PWM控制訊號並配合並聯式雙快速電磁開關閥，實現主動式氣壓減振系統之控制。隔振桌腳座內的氣墊式氣壓隔振器，原為被動式的氣壓隔振元件，本文加裝雙快速開關閥，調控其充氣加壓過程中產生的膨脹與收縮的變化特性，作為主動減振控制下的單動式氣壓致動器。 本文藉由軟體實現脈波寬度調變，並產生PWM訊號來控制快速開關閥開啟與關閉時間，如此可不必透過額外的硬體電路實現脈波寬度調變，並且快速開關閥亦具有較比例伺服閥廉價之優勢，使得系統可以在較低成本的同時亦可達到控制精度的要求。本文首先建立氣壓減震系統之數學模式， 簡化系統為一非線性時變方程式，再結合具 追蹤性能之以函數近似法為基礎之適應性滑動控制（ , Fourier series-based Adaptive Sliding Mode Control with tracking performance）進行控制器的設計，藉以克服氣壓系統之高度不確定性與時變問題。 本研究建立實驗系統進行即時控制實驗，實現四軸隔振桌的軌跡追蹤控制及主動式減振控制，最後為滿足氣壓隔振系統之實際需求，結合軌跡追蹤控制及主動式減振控制，發展為混合控制系統，進行不同外在干擾下之實驗，藉以檢驗此控制方法對於外在干擾之抑振效果。

This study aims to develop the active control for the four-axial PWM (Pulse Width Modulation) pneumatic isolation system. A novel concept using parallel dual-on/off valves with PWM control signals is proposed to realize the active anti-vibration control and position control. In this thesis, on/off valves by PWM realized by software are used. Therefore, additional hardware circuit is not required to implement PWM. In this study, we first derive the nonlinear mathematical model of the pneumatic isolation system. In the controller design, Fourier series-based adaptive sliding-mode controller with tracking performance is used for dealing with the uncertainty and time-varying problems of the pneumatic system. The experiments of path-tracking control and the active anti-vibration control are implemented in the four-axial pneumatic isolation system under different loading conditions. Finally, in order to satisfy the demand of the practical application in pneumatic isolation system, the hybrid control that combines the path tracking control and active anti-vibration control is developed and verified through experiments under different conditions.