摘要
現代的工廠中高精密機器的使用量快速增加，地板振動對精密度所造成 的影響也日益顯著。傳統隔離地板振動的方法是使用被動式隔離器或重新 設計機器系統。然而被動式隔離器的主要效能是在高頻部分，重新設計又 需較高的花費，因此近年來具有減振高效率的主動控制方法，逐漸成為研 究的焦點。本論文中提出一種主動式的振動控制方法。我們利用彈簧來支 撐受控系統的靜態荷重及抵消高頻部分的振動源；以電容式加速計和非接 觸式位移計作為量測系統輸出的感測器；線性的伺服放大器來放大控制系 統的控制信號；音圈馬達來取代被動式隔離器中的阻尼效應，如此可防止 阻對高頻減振效能產生的副作用。因為音圈馬達當中有些參數是未知的， 無法直接由運動方程式來求得系統的數學模型，因而我們採用頻譜分析法 求得系統之輸入電壓和加速度輸出信號之間的頻率響應，參考運動方程式 的階數來做系統鑑別。首先是以電容式加速計作為量測系統加速度輸出的 感測器，根據鑑別出的系統數學模型設計一RST多項式控制器，使負載平 台的慣性加速度，即使在地板有振動時仍保持在零。又為了要達到系統定 位控制，再增加非接觸式位移計作為量測系統相對位置輸出的感測器，所 以整個系統來說，是個單輸入兩輸出的系統。在控制器設計方面，使用現 態炕控制理論來設計，於是採用最佳化LQG控制法則，其中包含了狀態迴 授控制器與狀態估測器的設計；利用迴路轉移之回復方法，來恢復系統強 健性的效能；並且以位置誤差積分之控制法來消除系統位置輸出的穩態誤 差。在定位和抗干擾方面則以幾個實驗來做驗證，實驗結果顯示本控制系 統能達到0.0013mm的定位精度；同時兼具良好的抗干擾能力和0.058秒的 穩定時間。即使在動態系統的參數改變之後，即改變系統的負載，仍保有 原先系統的強健性、抗干擾性能及定位精度。
並列摘要
The population of precision machines is increased in today's machine shops. Asthe precision increases, the influence of floor vibration on machine accuracybecomes more prominent. Conventional methods for floor vibration isolation adopt passive isolators with springs and dampers. However, the passive isolator is more effect at the high frequency range. In recent years, researchers gradually turn their focus on the active vibration control approach to cancel the floor vibration.This paper proposes an acte vibration control method, which uses three springs to support the static load of a platform and to isolate the high frequency vibration from the floor. In addition, one micro-machined capacitive accelerometer and an eddy-current proximity sensor are used to measure the system acceleration and displacement. A DSP-based digital controller controls the output force of a voice coil motor to cancel the external vibration. To derive the unknown parameters of the aforementioned controlled system, we apply the sptral analysis method to find the transfer function between the input voltage of the voice coil motor and the acceleration signal of the payload. Based on the derived mathematical model, we design a RST polynomial controller which can keep the inertial acceleration of the payload to zero when the floor vibrates. In order to keep the relative displacement between the payload and the floor at a preset value, another state space controller is also implemented. This controller has two measurement inputs, i. e., pition and acceleration, and one control output, therefore the whole system becomes a single input, two output system. In the controller aspect, we apply the modern state-space control theory and the optimal control to design the state feedback control and the state estimator. The loop transfer recovery method is applied to recover the robust performance of a controlled system with an estimator. The controller also includes an integral control algorithm in order to cancel the steady-state error in position.Tverify the performance of the controller, we perform several experiments to investigate the robustness and the disturbance rejection capability. Experimental results show that our control system not only can achieve the position accuracy within 0.0013mm but also good disturbance rejection ability and fast settling time. Even the payload of the controlled systems is increased, the controller can still maintain good disturbance rejection and position accuracy without changing the parameters of the controller.