液滴接觸角及界面張力之自動化分析系統

Automatic Analysis System for Droplet Contact Angle and Interfacial Tension

侯權恩(Chuan-En Hou)

指導教授 ： 衛榮漢

國立清華大學/工學院/奈米工程與微系統研究所/碩士(2019年)

摘要

本研究主要開發液滴之界面張力自動化分析系統。為達精確量測及自動化兩大目標，系統必須在理論基礎、數學模型、馬達程式控制、影像處理等項目上，加以適度地結合，以求機台功能能夠完美呈現。本研究過程簡述如下，液滴界面張力的分析，含座滴法以及懸滴法兩種方法。關於界面張力的計算，本研究有引用其他文獻的理論，將其數學模型加以整理，並嵌入到正在開發的專案中。然而，在實際計算界面張力之前，液滴外框輪廓的偵測是首先要解決的問題。因此影像處理的技術、輪廓偵測、連通分量標記…等方法都被使用上。取得處理好的輪廓之後，才得以套用不同擬合的方法，將接觸角以及界面張力一併計算出來。除了量測的精準度提升之外，機台的自動化也是此次研究的另一項目標。本研究透過程式開發、整合機台的電機電控、並嘗試運用 AI 人工智慧中的深度學習技術，希望將機台自動化提升到更高的層次。例如: 以往液滴是靠人工方式釋放到量測平台上，現今改由程式控制，利用馬達推動針筒釋放液滴，來達成定量滴定的精確度；傾斜量測平台，進行動態接觸角量測的功能也得以被實現；操作介面的流暢度及電腦運算效能，均透過程式的設計有了顯著的改善。

關鍵字

接觸角量測系統 ； 界面張力分析系統 ； 座滴法 ； 懸滴法

並列摘要

This research mainly focuses on developing an automatic analysis system for the interfacial tension of droplets. In order to achieve both high accuracy and full automation, the system must be properly integrated on the basis of theoretical knowledge, mathematical model, motor control, image processing, etc. in order to achieve better performance. The research can be briefly delivered as follows, the analysis of the interfacial tension includes both sessile drop and pendant drop methods. Regarding the calculation of interfacial tension, this study has referred to theories of other literature and implemented their mathematical models into our project. However, it is necessary to obtain the droplet contour before proceeding to the calculation. Hence, image processing, edge detection, connected-component labeling, etc., have been utilized to obtain the droplet contour, and then, can the contact angle and the interfacial tension be calculated through various kind of contour fitting methods. In addition to the accuracy of the measurement, machine automation is also another major goal of this research. This study develops software, integrates motors and electronic parts, and even tries to use deep learning to enhance the machine automation capacity. For example, a droplet used to be dropped manually onto the measurement plate, but now this work can be done programmatically through syringe pump and the droplet quantity can also be controlled. Moreover, the tilting-plate measurement can also be conducted to measure the dynamic contact angle. The performance of the UI and the computation efficiency have also been improved by using profound programming architectures.

並列關鍵字

Contact Angle Measurement System ； Interfacial Tension Analysis System ； Sessile Drop ； Pendant Drop

參考文獻

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