以形狀記憶材料製作多自由度可調變吸振器之設計與結構減振研究

The Design and Fabrication of Multiple Degrees-of-Freedom Tunable Vibration Absorber Consisted of Shape Memory Materials and Its Use in Structural Vibration Reduction

白崇安(Chung-An Pai)

指導教授 ： 李春穎

國立臺北科技大學/機電學院/製造科技研究所/碩士(2013年)

https://doi.org/10.6841/NTUT.2013.00743

摘要

在精密工業上，外界振動干擾對產品的精度有很大的影響，常見的減振系統大多屬於被動式架構，對於外界動態之振動干擾上，減振效果有其限制，而為了不改變主系統設計的情況下加裝吸振器以達到減振的目的是為常用之技術。本文旨在研究設計與分析以智慧型材料形狀記憶合金(Shape Memory Alloy, SMA)包覆高分子聚合物(Shape Memory Polymer, SMP)套管製做之可調變吸振器(Tunable Vibration Absorber, TVA)。本研究中，利用超彈性合金(Superelastic Alloys, SE)線外包覆高分子聚合物，製作成螺旋彈簧形式，搭配質塊於自由端製作成可調變吸振器，通過不同電流以控制溫度改變吸振器剛性與阻尼效果來減低因外界干擾所產生之結構振動，以達到可調變減震效果。首先藉由頻譜分析儀擷取所建構之吸振器在不同電流下自然頻率與阻尼比，再利用有限元素分析(CAE)模擬吸振器的動態特性，改變螺旋彈簧的有效圈數找出適合主結構的規格，透過實驗找出不同振動頻率與振幅大小下的最佳減振效果所相應的電流值。針對不同頻率外界振動干擾作振動的抑制。實驗結果顯示若以1.5A電流加熱四層SMP吸振器可調頻率範圍約61.6%，對吸振器進行電流控制在振動抑制也有良好的成果有限元素分析誤差在13%以內，可預測吸振器可調變性能以及對主結構耦合程度。

關鍵字

智慧型材料 ； 超彈性記憶合金 ； 可調變吸振器 ； 有限元素分析

並列摘要

This study used hybrid smart materials- shape memory alloy core enclosed by shape memory polymer (SMP), to design a tunable vibration absorber for vibration reduction over a wide frequency range. The superelastic wire was trained into helical spring and sleeved with several layers of SMP to form the structural part of the absorber. Different electric currents were employed to control the heating and temperature of the shape memory materials in order to tune the dynamic characteristics of the absorber. The experimental results showed that using 1.5A current to heat the four SMP layers sleeved vibration absorber the adjustable 1st modal frequency range can reach 61.6%. After the assembling of absorber onto the main structure, the tunable capacity of the absorber under different control currents were measured. It was found that the modal frequency results from finite element simulation were within 13% error comparing with measurements.

並列關鍵字

Smart Materials ； Hybrid Shape Memory Materials ； Tunable Vibration Absorber ； Finite Element Simulation

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