具有觸覺回饋的磁流體按鍵

Ferro-fluidic Button with Tactile Feedback

蔡孟剛(Meng-Kang Tsai)

指導教授 ： 邱一

國立交通大學/電機學院/電機與控制工程系所/碩士(2018年)

摘要

本論文使用磁流體(Ferrofluid)作為按鍵的設計主軸，其具有高磁導率以及對於受到外加磁場後產生形變的特性，使其應用於許多方面，如醫學、航太與光學…等。按鍵是提供使用者一個觸覺的設計，利用磁流體受到外加磁場後會產生形變來作為此按鍵的致動原理，除此之外，還加上了感測機制在此按鍵中，由於線圈之電感值會因為周遭環境之磁導率變化而改變，所以在按下按鍵時，線圈之電感值也會跟著改變，藉此來做為壓力變化的量測。
本論文設計兩種不同的結構的按鍵，其兩者結構均由磁流體包覆感測與致動線圈，並以PDMS薄膜覆蓋其頂部。設計一底部無補償空間，設計二底部設有補償空間。量測結果顯示設計二的整體效能較好，在相同電流下，以2 A為例，設計一之薄膜平均正位移分別為1.83 μm，設計二則為15.04 μm。而感測部分在
0～6.4 kPa的壓力區間其電感值有受壓力而減少的趨勢。

關鍵字

磁流體 ； 觸覺回饋 ； 按鍵 ； 壓力感測器 ； 致動器

並列摘要

This thesis uses ferrofluid to design and implement a tactile button. It has high permeability and can be deformed by applied magnetic fields. So it can be used in various applications, such as medicine, aerospace and optics, etc. The button is a tactile design that provides the user with a touching feedback. The actuation principle of the designed button is that ferrofluid is deformed by the applied magnetic field. This design also includes the sensing mechanism. The inductance of the coil changes because the permeability surrounding the coil changes. Therefore, when the button is pressed, the inductance of the coil will also change. Then the inductance change is used to detect the pressure.
Two buttons with different structures were designed in this thesis. Both actuating and sensing coils of the structures were covered by ferrofluid. The top of the buttons was covered by PDMS membranes. Design 1 was without compensation cavity and, conversely, design 2 had compensation cavity. The measurement results showed that the overall performance of design 2 was better. For example, when the current was 2 A, the average positive displacement of the membrane is 1.83 μm in design 1 and 15.04 μm in design 2. The inductance decreases with the pressure between 0 to 6.4 kPa.

並列關鍵字

Ferrolfuid ； Tactile feedback ； Button ； Pressure sensor ； Actuator

參考文獻

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