以熱聲效應改善微電子裝置散熱的研究
近年來在熱聲效應方面的研究產生了許多新發明，如冰淇淋冰箱與太空梭溫控系統等。然而，將熱能轉換成聲能的熱聲引擎，在散熱方面的效用只有被提起而從未被實際應用。本研究參考美國賓州大學「聲學雷射」裝置來研究熱聲引擎的特性，並提出一個以熱聲效應改善微電子器材散熱的裝置。它的優點是由電子裝置產生的熱即可啟動熱聲效應，而熱聲效應所加強的熱對流可降低該電子零件的溫度。實驗中發現透過熱聲效應的強烈散熱，可以大為降溫，由200℃降為50℃左右，這正是當代電腦內中央處理器（CPU）的工作溫度範圍。未來的研究可以針對陣列式的熱聲散熱裝置進行測試。In this project, the characteristics of the thermoacoustic engine were first studied using the “Acoustic Laser” concept. A passive thermoacoustically enhanced convection engine capable of improving the cooling effect of microelectronic devices was then proposed. This design has the advantage that no additional energy input is required, a contrast to the usage of mini-fans in today’s computers. A testbed combining a heated NiCr wire with a glass tube was used to examine the overall cooling effect. In order to evaluate its performance, we measured the following parameters: radiation, convection, conduction, and acoustic radiation. We found that the heat caused by today’s microelectronic devices is sufficiently high to trigger the thermoacoustic effect. Based on this finding, we designed a new configuration to utilize this thermoacoustically enhanced convection to significantly lower the temperature. Our approach has a potential application to tackle the heat problems caused by the rapidly advancing microelectronic devices.
動力機械(內燃機)模型引擎之研究
最古老之動力機械為蒸氣引擎，在早期蒸氣火車發電機皆由蒸氣引擎發展而來，本研究即利用最古老之蒸氣引擎(俗稱飛龍引擎)之製作，以探討內燃機之基本理論以作為模型引擎設計之基礎。在飛龍引擎製作中，歷經引擎無法轉動之痛苦，並極力找尋一百年前發明蒸氣引擎之同樣思考，最後找尋到引擎啟動之合適尺寸，再用其尺寸延伸做實驗，以發展其理論，最後發現引擎設計之重要變數如管長﹑火焰﹑本身重量均為設計中重要因數，最後用正式機械設計方式完成第四代引擎亦正式運轉，可見本蒸氣引擎之設計基礎具有相當實用之基礎。The oldest locomotive engine was the steam engine. All early steam locomotives were developed from the steam engine (Heron engine) and this research project uses the Heron engine to explore the fundamental theories behind the internal combustion engine as a model for basic engine design. During the production stage of the Heron model, there were difficulties with engine rotation, and so efforts were made to find the same thought processes involved in producing the steam engine 100 years ago. The dimension appropriate for moving the engine was first found, and then the idea was extended with experimentation of the size in order to develop the theory of engine design. In the end, the length of the steam hose, the strength of flame, and the actual weight of engine were all found to be important factors of design. Finally, the fourth generation Heron engine was able to rotate properly using the proper engine design method, so it can be seen that the fundamentals of steam engine design has quite a practical engine design basis.
無尾翼飛行器之穩定與控制
無尾翼飛行器(Tailless Aircraft)在軍事上的價值極大，且對於目前正在起步的微飛行載具(Micro Air Vehicle)而言，亦是值得嘗試與投資的。然而，由於無尾翼飛行器缺乏用以平衡的水平尾翼，造成其靜態的不穩定，即使設法提高靜態穩定特性，但其氣動力阻尼低、穩定性仍舊不佳。操縱上更是困難，在飛行穩定性與控制系統設計上極其挑戰性。本研究目的在探討無尾翼飛行器之穩定性與控制技術，改善其先天之不穩定特性，考慮之項目有縱向靜態穩定性、動態穩定性、控制面與組件配置等因素等進行詳細之探討。首先，找出了適用於無尾翼飛行器之Reflex翼形，接著建立無尾翼飛行器之非線性縱向動態模式，然後針對一翼展8Ocm之小型飛行器進行外型設計，並觀察分析其實際飛行狀態，再以理論與經驗公式估算無尾翼飛行器之氣動力導數，探討其飛行穩定與操控性能。此外，並運用古典控制PID控制法則，設計控制器進行非線性受控系統之動態響應模擬。由模擬結果可看出，經由翼剖面改變與控制系統的輔助下，大幅提高了其性能，使得無尾翼飛行器克服了先天的不穩定特性，更提高了其發展空間 The tailless aircraft has a great value on the military use. Meanwhile, it is worthwhile to try and to invest in it for the investigation of MAV(Micro Air Vehicle), which is being developed now. However, because of lacking horizontal tail which is used for balance, the tailless aircraft is static unstable. Even with the attempt to enhance its characteristics of static stability, the stability of the tailless aircraft is still poor for the sake of it's low damping in aerodynamics. Therefore, it is a challenge to flight stability and control system designing. The purposes of this research are to study the stability and the control technique of the tailless aircraft. To improve its congenital lacking of stability, thought over the longitudinal static stability, dynamic stability and control system. First, find the "Reflex" airfoil is suitable for the tailless aircraft. Second, set up a non-linear and longitudinal dynamic model of the tailless aircraft. Third, design an 80cm span small airplane. Hence, observe and analyze its flying condition. Finally, utilize the theoretical and experiential equations to estimate the aerodynamic derivatives and investigate its stability and controllability. Besides, use the PID controller to proceeded the time-response simulation of the non-linear system. The result of simulation shows that the performance is improved through the change of the airfoil and with the auxiliary of the control system. With this improvement, the tailless aircraft overcome the congenital lacking of stability to broaden its utilization potential.
Design of a Computer Interface for a Robotic Arm Actuated by VHB 4910
Recently, there have been several researches aimed at the feasibility of electroactive polymers (EAPs) replacing motors as robotic actuators – the driving forces behind mechanical devices. However, current EAP actuators are either hard to control or incapable of discrete accurate movements. The research aims to design a computer interface that makes it possible for the electroactive polymer, VHB 4910, to become an effective substitute for bulky motors in effecting precise and accurate control of a robotic arm.
電容超音波膠體金粒子電位調控系統研發
費曼曾說：There is plenty of room at the bottom。喬治亞理工大學的Mostafa El-Sayed 教授發表的癌細胞辨識、與科學月刊報導『台大抗煞一號』引發我們對膠體金粒子的興趣。膠體的性質主要是由界達電位 (zeta potential)決定。參考台科大、成大、中山…等超音波應用研究，提出改良篩選物理法製造之膠體金粒子的儀器設計與製作。經沉降過濾可達平均粒徑 100 nm；而離心式篩選機與超音波管式篩選機可達平均粒徑30 nm。篩選後的膠體粒子以電容原理調控膠體金粒子之界達電位 (zeta potential)，成功地從-30 mV 提升至-59 mV，並發展成電容超音波界達電位控制儀(Capacitor Ultrasonic Zeta Potential Controller)。以膠體金粒子與蛋白質鍵結量來測試調控界達電位的效果，發現蛋白質鍵結量之增加曲線與界達電位的增加曲線的增加趨勢相似；此功能的發現對於生物科技方面的應用應會有很大的幫助。透過界達電位控制系統，本研究達到費曼先生所期望的「在原子或分子的尺度上來加工材料和製造設備」。“There is plenty room at the bottom.” The words of Mr. Feynman are the beginning of nano technology. Mostafa El-Sayed, a professor of Georgia Institute Technology, identified cancer cells through nano gold-antibody complex. So, our study focuses on the zeta potential of colloidal gold particles. At first, the filtering method and equipments were developed. The theories were based on the ultrasonic studies of universities such as National Taiwan University of Science and Technology. Then the colloidal gold’s sizes were filtered to100 nm through settling. At last, by using Continual-Filtering Centrifuge (CoCe.) and Tube Well Mass (TW-MS), the mean particles sizes can be filtered to 30 nm. The most important results are: Zeta potential of the gold colloid was controlled with Capacitor Ultrasonic Zeta Potential Controller. The zeta potential can be raised from -30 mV up to -59 mV, which is -20 mV higher than the conventional pH-changing way. The function of zeta potential to protein binding quantity was tested. The increasing curves of zeta potential and protein binding quantity were similar. This property would be a significance of biotechnology. Thourgh Capacitor Ultrasonic Zeta Potential Control system, the zeta potential’s limitation of gold colliod, which is produced by SANSS (Submerged Arc Nanoparticles Synthesis System), can be controled in a wilder range. The study which is focused on nano-scale, like the wish of Mr. Feynman – “To manufacture material and produce equipment in atom and molecular scale”.
聽音辨位--聲波的測量應用
本實驗設計主要是以波的傳送速度(特別是聲波)，以及接收收到的時間值來做實驗、運算、討論。而其特點是為了應用於實際生活中，做了許多異於平常測量方法的設計。主要是使用時間差(｜t1–t2｜V=發聲器到兩感應器的距離差 )來消彌掉一般測量時，需要採取同步的條件，說明如下：
1. 由以上的圖中，t1’ = T + t1 為實際由感應器開始感應到感應器#1 接收到訊號的時間；同理，t2’ = T + t2 為實際由開始感應到感應器#2 接收到訊號的時間。而T 為感應器開始感應到發聲器開始發聲的的時間(之後的 T 皆為如此)。由以下式子得知：
｜t1’ - t2’｜=｜( T + t1 ) - ( T + t2 ) ｜=｜t1 - t2｜及為本實驗所需的時間差。利用減法將T 消除，便及為發聲器與感應器不必採取同步，此為本實驗目標以及優點之一。
2. 之後的公式推導中，實際由感應器開始感應到感應器接收到訊號的時間中，表示為t1、t2、t3……以此類推。
像是市面上販售的反射式測距器由於其直線性的限制，在我們可負擔的情況下，就只能做一維的測量，而在本實驗中，我們使用多個感應器，而可測量至二、三維空間，並使測出的物體由相對位置轉為絕對位置。再加上正在計劃中的測量儀器改良與自製，例如利用電腦的音效卡接上麥克風或是其他感測器，以及電子零件、電路的組合與設計。而在於一般的實際應用面上可配合工業的破壞性檢測，甚至是橋樑的斷裂處、各種振源的測量，亦或是人員的搶救，都應有不錯的效果與利用價值。
1.The major design of experiment is to spot the location of an object by experiment, calculating and discussing of such figures like the transmission speed of the waver (especially sound wave), plus time value of the receptor and so on to get the result. 2.In practice, the ordinary measuring method has to be implemented under the circumstance of synchrony: however, the distinguishing characteristic in the experiment is to overcome such restriction with the use of the “time lapse” concept. 3.The reflecting measuring instrument on the market is limited by its “straight-line characteristic.” Instead, we use multiple sensors to spot the absolute location of an object in its 1-D, 2-D, 3-D form. 4.We have now been working on the improvements of the measuring instruments, for instance, using sound cards to connect to the microphone to make a new sensor; also, the redesign and combination of other electric parts and circuits are also under construction. 5. We plan to apply the experiment not only in spotting the location of an object but also in further spotting the location of vibration coming from various objects (e.g. in the use of rescue).