磁驅動微夾持裝置的設計與量測

Design and Measurement of Micro Grippers Driven by Magnetic Fields

陳健烽(Jian-Feng Chen)

指導教授 ： 蔡睿哲

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.10563

摘要

本篇論文主旨在論述我們所設計及製造的磁驅動微夾持裝置，它有元件尺寸小、輸出力量大、驅動距離長、低耗能、低工作溫度甚至可以在導電液體的環境下工作等優點。layout經由軟體L-edit繪製出，透過MetalMUMPs製程，將鐵磁性材料鎳當作元件主結構，製作出磁驅動的微夾持裝置。
我們所設計的微夾持裝置依照結構上分成三種：Nitride相接雙自由度夾頭之夾持器、Nickel相接雙自由度夾頭之夾持器以及三自由度夾頭之夾持器。Nitride相接雙自由度夾頭之夾持器在驅動端的部份鎳棒與鎳棒間採用silicon nitride相接，所以我們預期它的結構較具彈性，位移較大；Nickel相接雙自由度夾頭之夾持器顧名思義在驅動端的部份是鎳棒與鎳棒直接相接，所以我們預期它的輸出力量比較大，但結構可能不易產生位移；至於三自由度夾頭之夾持器我們使用通電流並施加磁場在元件上產生勞倫茲力的方式，讓夾頭產生第三個維度的運動，也就是夾子手臂的前後平移。
針對此三種結構我們都各自設計了多組不同尺寸的微夾持裝置，透過理論及實驗的分析來找出不論在位移或夾持力量上表現最佳的元件。實驗結果在in-plane motion上可用磁驅動以及電熱驅動；在out-of-plane motion上，透過加z方向的外加磁場，可讓夾子手臂向上抬升，基本上外加磁場越大，抬升的角度也越大。我們針對晶片中的十二個元件依尺寸分成五種type，並在外加Z方向磁場與抬升角度上作分析，得知type 1中的元件二抬升效果最好，抬升角度可達34.964度；並發現相同的手臂尺寸，若在nitride中加入polysilicon，抬升的角度會變小。

關鍵字

磁驅動 ； 微夾持裝置 ； MetalMUMPs

並列摘要

In this research we have designed and fabricated magnetically actuated micro-actuators which are advantageous in small sizes, high forces, long actuation distances, low power consumption and working temperature. Furthermore, they can be suitable for applications in conductive fluidic environments. We use the commercial software L-edit to draw the layout, and the MetalMUMPs process to fabricate the micro-actuator. We use ferromagnetic materials to build the main structure, and design the magnetic micro gripper.
According to the structure of the micro gripper, there are three types: the Nitride-connection 2-degree-of-freedom micro gripper, the Nickel-connection 2-degree-of-freedom micro gripper, and the 3-degree-of-freedom micro gripper. The Nitride-connection 2-degree-of-freedom micro gripper is connected by silicon nitride between the nickel beams at the actuator, so we expect that the structure of the gripper is more elastic than the Nickel-connection 2-degree-of-freedom micro gripper and has larger displacement. The Nickel-connection 2-degree-of-freedom micro gripper is directly connected between nickel beams, so we expect that it has lager forces. The 3-degree-of-freedom micro gripper has one more degree of freedom than the others. Due to the Lorentz force, we can generate the y direction displacement of the gripper arms.
We design different sizes of the three structures respectively, to find the one with the best performance. The results show that we can use magnetic or electro-thermal actuation in the in-plane motion. When we apply magnetic field in z direction, the gripper arms will lift up. Basically, the larger the magnetic field, the larger the elevation angle is. We also show the relationship between magnetic fields and the elevation angles. We classify the 12 devices into 5 types according to the gripper arm sizes and discover that the device 2 in type 1 has better performance in elevating. We also discover that the grippers with polysilicon have smaller elevating angle than the grippers without polysilicon.

並列關鍵字

magnetic actuation ； micro gripper ； MetalMUMPs

參考文獻

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