應用兩軸旋轉平台於基座干擾下之主動式減振研究

Vibration Suppression of a Pan/Tilt Platform Due to Base Excitation

鄭如傑(Ru-Jay Zheng)

指導教授 ： 蕭俊祥

國立臺北科技大學/機電學院/機電整合研究所/碩士(2005年)

摘要

本論文針對兩軸旋轉平台所受到基座干擾下的振動問題，進行減振研究。本論文使用主動式振動控制的方法，分別利用兩個感測器來量測各平台的轉動速度資料量，再透過假積分有效地產生角度資料來當回授訊號。並且設計兩種不同的控制器，包含運用Filtered-X LMS演算法之回授式控制與自我調節控制器，這些控制器可適時產生主動式的反振動訊號，以使平台獲得減振，達到定位目的。
本實驗將由史都華六軸平台產生單頻與複頻的激振干擾源，在單頻結果部分，對於個別平台的控制可達到超過20 dB，而兩軸平台同時控制的效果可達12∼18 dB；在複頻結果部分，對於個別平台的控制在8∼12 dB之間，而兩軸平台同時控制的效果可達8∼11 dB。因此，本實驗所採用的兩種控制器的確都能在各種不同的振動干擾條件下而有一定的減振結果，且都能在20秒以內達到此一效果。

關鍵字

假積分 ； Filtered-X LMS演算法 ； 自我調節控制器 ； 史都華六軸平台

並列摘要

This thesis aims to attenuate vibrations of a two-degree-of-freedom pan/tilt platform subjected to base excitation. Active vibration control is employed in the experiment and two rate sensors are used for measuring respective yaw and pitch rate of the pan/tilt platform. The measured rate signals are then pseudo-integrated to have the angle displacements for feedback control. Two active vibration controllers of the Filtered-X LMS algorithm and self-tuning regulator are designed to produce a suitable anti-vibration for attenuating platform vibrations.
A six degree-of-freedom Steward platform is utilized for providing single and dual frequency disturbances to the base of the pan/tilt platform. Experimental results show that for single-frequency base disturbances, over 20 dB vibration attenuation can be obtained for independent yaw or pitch control, whereas 12~18 dB vibration reduction attained for simultaneously yaw and pitch vibration control. For dual-frequency base disturbances, 8~12 dB vibration attenuation can be obtained for independent yaw or pitch control, whereas 8~11 dB vibration reduction attained for simultaneously yaw and pitch vibration control. Therefore, the two active vibration controllers of Filtered-X LMS algorithm and self-tuning regulator are shown to have capabilities for vibration attenuation under different disturbance conditions and within short time of less than 20 seconds.

並列關鍵字

Pseudo-integration ； Filter-X LMS algorithm ； Self-tuning regulator ； Steward platform

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