磁黏滯式旋轉阻尼器之設計開發與特性研究

Design and Development of a Magnetorheological Rotary Damper And Research on its Performance

石逸鵬(Yi-Pong Shi)

指導教授 ： 黃光裕

國立臺灣大學/工學院/機械工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.00580

摘要

本論文整合永久磁石和電磁線圈，利用磁場平衡和磁黏滯液體設計出半主動式旋轉阻尼器，以適用於人體膝關節之輔助支撐為開發目的。磁黏滯式旋轉阻尼器之作動方式要在未提供驅動電流時，有較高之支撐力(矩)，隨著驅動電流之增加，支撐力(矩)會變小。依據剪力作動原理以及考慮系統性能需求，旋轉式阻尼器採用多片式旋轉環片結構。永久磁石提供固定磁場給磁黏滯液體以產生較高支撐力(矩)，電磁線圈作動時則提供反相磁場吸引永久磁石之磁力線，使磁力線遠離磁黏滯液體工作區，來降低支撐力(矩)。系統以模組化架構建構，可以依據各別的需求來增減支撐力矩。
在永久磁石磁場單獨作用下，磁黏滯式旋轉阻尼器可提供1.47 Nm靜扭力矩；在驅動電流0.3A作動下，電磁線圈可以產生磁通密度約383.6 Gauss，靜扭力矩下降則至1.33 Nm。導磁心軸和導磁夾板之間組裝偏心使作動磁場局部集中在部份導磁心軸上，而無法有效地傳到磁黏滯液體中。磁迴路之設計、製作和組裝的品質關鍵著磁黏滯式旋轉阻尼器之性能。

關鍵字

磁黏滯液體 ； 半主動式 ； 旋轉式阻尼器 ； 模組化 ； 多重環片

並列摘要

This thesis integrates the magnet and the electromagnetic coil to build up a semi-active rotary damper by using the field balancing concept and the magnetorheological fluid(MR-fluid). The aim of the development of this magnetorheological rotary damper is to fulfill the supporting function for human knee. The rotary damper in the inactive state should produce higher damping force/torque than it in the current charging state. Based on the shear-mode working principle and the performance requirement, the rotary damper utilizes the rotary structure with multiple rings. The permanent magnet provides a constant magnetic flied to MRF in order to generate high damping force/torque, and the electromagnetic coil is used to provide an inverse magnetic flied to attract the magnetic flux of the permanent magnet from MR-fluid, so as to reduce the damping force/torque. Through the modular structure the rotary damper can be easily modified according to various requirements.

Only under the permanent magnet, the MR damper can provide a steady torque of 1.47 Nm and a damping coefficient is 0.0055. The electromagnetic coil generates an induction of 383.6 Gauss for the driving current of 0.3 A, and the reactive torque decreases to 1.33Nm. The unsymmetrical assembly gap between the shaft and the side plant lets magnetic flied pass through the shaft but not transfer to the main working MR-fluid. The performance of the MR-damper is significantly influenced by design, manufacture, and assembly qualities of its magnetic loop.

並列關鍵字

magnetorheological fluid ； semi-active ； rotary damper ； modular structure, ； multiple rings

參考文獻

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