目前不論是光碟機或硬碟機，其轉速要求越來越高，以便縮短資料讀取之時間。但高轉速通常會引發轉動軸及基座較大之振動，這使得光碟機或硬碟之減振機構設計變得格外重要。過往減振設計，以改變減振器之質量或直接在基座支撐點使用減振材料使其具有減振效果。但如此之設計，所使用之減振器則需量身定做，來因應各種光碟機，不同的系統需要不同的減振器，這樣將大大增加成本。 故在本研究中，我們將使用一種更符合經濟成本，且在不改變減振器材料及更動光碟機之大部分架構的方式之下，僅以改變減振器位置的方法來達到減振的效果。 此外，本研究將平板 與 方向的轉動角作幾何上非線性化假設，運用Lagrangian Method導出其運動方程，以數值Runge-Kutta法求其結果，分別再以小擾動之數值解、頻率響應之數值解，以及解析法加以佐證。如此，將可允許本模式捕捉非線性之較大形變量的運動狀態，對於日後微量化之非線性現象也可一併模擬之。 為了推廣本模式之應用，本論文除了分析光碟機構的減振之外，也將其與旋轉翼耦合，作同樣之減振分析，以期運用於微型旋翼直昇機之減振機構設計當中。由研究結果發覺，將減振器置於旋轉機構之基座四端，可有效降低振動幅度，此數據期望能對相關產業作為測試、設計之參考。 Vibration reduction of an optical disk drive or any of the rotating device deck such as rotary-wing coupled swash plate system by using a vibration absorber is presented in this thesis. The traditional vibration reduction mechanism using in normal optical disk is using the vibration isolator consists of a resilient member (stiffness) and an energy dissipater (damping). Once the system of the disk drive is set, it is difficult to change the configuration, and so, the vibration reduction is limited for further modification. Furthermore, the traditional vibration reduction mechanism using in helicopter is not suitable for a mini-scaled or micro-scaled helicopter due to its complicate mechanical device and heavy weight. Furthermore, for the mini-scaled unmanned rotary-wing aircraft, it is practically difficult to overcome the rotor shaft vibration by only the servo control. In this thesis, a new vibration reduction device is presented for the optical disk drive or the mini-scaled unmanned rotary-wing aircraft.
In this research, an optimized position of a mass-spring-damper vibration absorber is proposed for a rotating mechanism device (such as optical disk drive or rotary-wing and deck coupled system). A nonlinear 3-D theoretical model for a deck is established by Lagrange’s equation. A 2-bladed rotor and deck coupled aeroelastic system with vibration reduction device is presented for further analysis and optimal design for the location of the vibration absorber. The wake effect is assumed to be a constant and included for the rotor aerodynamic formulation. The results in both time domain and frequency domain are checked by several numerical methods. The special case analytical solution is obtained by the Multi-scaled Method. The results from the numerical and analytical methods are agreed with each other very well. This research provides preliminary vibration reduction design for industries. It is found that the now existing disk drives vibration amplitudes can be reduced by simply added the absorber but without changing the main configurations.
