壓電式光學讀寫頭精密定位之強健控制器設計與驗證

Robust Control Design for Precision-Positioning Optical Pickups and its Experiment Verification

鍾明勳(Ming-Hsun Chung)

指導教授 ： 黃健生

中原大學/工學院/機械工程研究所/碩士(2004年)

https://doi.org/10.6840/cycu200400603

摘要

本文提出一應用在光碟機中的兩階段致動器，該致動器用於光碟機中讀取頭之定位，其包含一微調壓電(PZT)致動器和一粗調音圈馬達(VCM)。在控制法則的選用上，我們將設計兩階段伺服系統基於強健 控制器來達到致動器之定位，之後我們將再設計一重複性控制器於兩階段伺服系統中，其目的在於消除由碟片旋轉所產生之週期性干擾。要達到上述之目標，首先我們可以藉由實驗鑑別來得到PZT致動器和VCM之數學模型，之後進行強健 控制器之設計。設計的過程是經由強健控制理論 分析法的設計，最後可以得到一兩階段強健 最佳化控制器。另外在抑制碟片干擾方面，由於DSP與感測器的限制，我們將會設計一重複性控制器於兩階段伺服系統中，最後達到定位與抑制牒片振動的功效。電腦模擬以及實作驗證將會在以下的論文中證明上述控制器設計之優劣。

關鍵字

壓電致動器 ； 音圈馬達 ； 強健控制器 ； 重複性控制 ； 兩階段致動器

並列摘要

This study proposes a dual-stage lens actuator used for optical disc drives, which includes a piezoceramic parallel-beam fine actuator and a voice coil motor (VCM) as the coarse one. The positioning algorithm of the objective lens consists of robust fine/coarse controllers designed based on mu-synthesis and a repetitive controller to further reduce effects of disturbance on the positioning performance. To accomplish the aforementioned goals, the dynamic model of piezoceramic parallel-beam and VCM are first established and then identified by experiments. Based on these identified models, the system dynamics is represented as a standard form, which is ready for mu-synthesis to design robust controller. Performing a known optimization, the desired robust controller to conduct fine/coarse positioning can be obtained. Following the control design, the repetitive controller is forged to reduce further the effect of disturbance based on the periodic nature of the disturbance. Simulations and experiments are conducted to validate the performance expected by previously-designed controllers.

並列關鍵字

voice coil motor ； repetitive control ； control. ； Dual-stage actuator ； piezoceramic actuator

參考文獻

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