全國中小學科展

工程學

分析鴨式布局對大型無人定翼機穩定性影響與其利弊探討

遙控技術進步快速,無人機由玩具演進入戰場,甚至在科學研究中成為無往不利的利器。本研究旨在探討若將MQ-9大型無人機捨棄匿蹤性,改採鴨式布局是否對其飛行效率及穩定性能達到更好表現。 以自製風洞為主要研究器材,此外也使用電子儀器測量,推導出升力係數及其計算過程。得升力係數與爬升能力呈正相關。 本研究結果如下: 一、 比較採常規布局模型與採鴨式布局模型於不同攻角下的升力係數變化,攻角0 ˚ ~15˚ 時採以常規布局模型有較好升力係數,但與鴨式布局模型差異不大。且採鴨式布局模型較採常規布局有較大的失速攻角(20˚)。 二、 常規布局模型與鴨式布局模型於不同攻角下的阻力係數變化,攻角0 ˚ ~15˚ 時採以常規布局模型有較大阻力係數,但與鴨式布局模型差異不大。 三、 以溫度流探討採鴨式布局模型比較採常規布局模型,其主翼下翼面溫度較低,可得採鴨式布局模型翼面下流速、密度、壓力較採常規布局模型小。 四、 自行設計Python程式統計側風狀態下採兩種布局之MQ-9風洞模型翼梢雷射光點閃爍次數,採常規布局模型擺動頻率較鴨式布局高。 五、 將方格紙上反射光點軌跡進行影片格放分析,並進行FFT模式分析,探討機翼運動模式。推測常規布局模型較多為「擺動」;「振動」則較少發生。鴨式布局模型較多為「振動」;「擺動」則較少發生。 六、 對放大機翼面積進行氣流分析,常規機翼模型攻角0 ˚ 時觀測到機翼有邊界層現象,15 ˚時觀測到層流分離現象,製造機翼表面壓力差並提供升力;鴨式機翼模型攻角15 ˚、20 ˚觀測到渦流現象,有助減輕主翼受力負擔並提供額外升力。 將大型無人定翼機結合鴨式布局,飛行時有更好的效率提升,以其高爬升比及穩定度高的特性,能在相同油耗下有更長遠的航程,也符合綠色科學發展與環保理念。

An Analysis and Optimization of Double Parallelogram Lifting Mechanism

Double Parallelogram Lifting Mechanism (DPLM) is a compact and stable lifting mechanism with a large extension range widely adopted in robot designs. Rubber bands and springs are often installed on the DPLM to lighten the motors' load and maintain its height, yet the installation positions are often obtained through trial and error. This project aims at finding the optimal rubber band installation positions for DPLM using modeling and optimization techniques. A mathematical model which describes the forces and moments acting on all the linkages of DPLM was derived based on the conditions for the static equilibrium and verified with a 3D simulation software. A genetic algorithm (GA) was implemented to optimize rubber band installation positions, which managed to find solutions with the overall root-mean-square- error (RMSE) of the net moment less than 2 for 2 to 6 rubber bands. A further statistical analysis of 50000 random rubber band samples showed that installing rubber bands in triangles is the best solution with the overall lowest RMSE. A test was conducted with a prototype of the DPLM and the results were consistent with our model and optimization. This project derived and verified a mathematical model for the DPLM, and found the optimal way and positions to install rubber bands. The results of this project provides a theoretical basis for controlling DPLM with rubber bands, allowing it to be further adopted in industrial robots that require repetitive lifting and lowering such as inspection robots and aerial work platforms.

漂浮城市~創意的隔震設計

利用桌面曲棍球的玩具,啟發本組做出能讓建築物漂浮減震的設計,並使用樂高EV3教育模組設計實驗來探討其中影響減震效果的變因。本組發現:只要在建築物底部兩個介面中充入空氣形成「空氣墊」,就可以減少摩擦力而達到減震的效果,另外也發現,讓建築物懸浮的空氣墊氣壓越大、底面積越大、重量越輕、接觸底面越光滑、及在高頻的地震下,其減震的效果越好。此外,為了減少因為減震產生的建築物滑動而超過原本建築物設計活動的範圍,使用此隔震設計的建築物也需要設計使用阻尼或避震墊在建築物的周邊,以避免滑動時撞壞建築物。最後希望提出此創意的隔震設計讓業界有不同的思考及靈感,做出將來更好的建築物避震設計,讓人們可永久免於地震的傷害。

Development of an Audio Modulated Tesla Coil

Originally, the Tesla transformer was developed to transmit energy and messages wirelessly. But it did not prove itself for either of these applications, so today it is only used for research purposes. Over time, the Tesla transformer has evolved and improved. Today it is possible with Tesla transformers to generate powerful and highly precise controlled discharges. During operation, impressive high-voltage discharges occur at the transformer. A tesla transformer is basically a high voltage generator that achieves a voltage boost by using two magnetically coupled LC series resonant circuits of the same resonant frequency. The Dual Resonant Solid State Tesla Coil (DRSSTC) built in this work has a high power IGBT half bridge module to excite the primary resonant circuit at the resonant frequency. The IGBTs are driven in such a way that audible pressure waves, and therefore music, are generated by the electrical discharges at the high voltage electrode. Within the scope of this work were the following two questions: - How is a DRSSTC designed and built? The DRSSTC system realized in this work is about 80 cm high and reaches about one-meter-long discharges. The design, development, and construction of the transformer are documented in detail and extensively in this thesis. - How does one measure an electrical voltage of 200,000 V, which changes sign more than 100,000 times per second? Two approaches have been taken to measure the voltages. Derived from the energy balance of an ideal capacitor and an ideal coil, a secondary voltage of about 200 kV was calculated via secondary current measurement. The second approach uses a voltage measurement via an in-house developed measuring electrode and a calculated divider ratio between the measured voltage and the secondary voltage. A relatively unrealistic secondary voltage of about 750 kV was measured since the divider ratio depends on approximate values. Nevertheless, the measuring electrode can be used for investigations of the voltage curve, or the divider ratio can be calibrated via the secondary current measurement. The development of such a transformer laid the foundation for much further research and scientific analysis.

風驅電「極」- 陣列式無扇葉風力發電機

「無扇葉風力發電」是一種新型的能量擷取研究,透過渦流引起的震動將風能轉換成電能。傳統渦輪式風力發電利用風推動扇葉旋轉發電,受限於風向、成本、噪音及體積等問題無法在內陸得到普遍。先前已有外國公司發表初步的機構設計與發想概念,但目前仍只能針對單一風向進行發電。本研究提出新型機構設計,有效的運用了多方向風源,降低了風能的浪費。為了瞭解渦激振動與各項變因之間的關係,我們設計了多項實驗,藉由影像分析軟體Tracker,得出不同風速下桅杆晃動振幅與頻率之關係,並利用實驗分析採集器LabQuest 2,精確的得出單位時間內的平均流速與電壓變化,獲得流速與電壓頻率特性。 根據實驗結果,隨著風速的增長,電機產生的峰值電壓會有2次方的增長,且桅杆晃動頻率與風速和支點位置並無直接關係。

Development of an Audio Modulated Tesla Coil

Originally, the Tesla transformer was developed to transmit energy and messages wirelessly. But it did not prove itself for either of these applications, so today it is only used for research purposes. Over time, the Tesla transformer has evolved and improved. Today it is possible with Tesla transformers to generate powerful and highly precise controlled discharges. During operation, impressive high-voltage discharges occur at the transformer. A tesla transformer is basically a high voltage generator that achieves a voltage boost by using two magnetically coupled LC series resonant circuits of the same resonant frequency. The Dual Resonant Solid State Tesla Coil (DRSSTC) built in this work has a high power IGBT half bridge module to excite the primary resonant circuit at the resonant frequency. The IGBTs are driven in such a way that audible pressure waves, and therefore music, are generated by the electrical discharges at the high voltage electrode. Within the scope of this work were the following two questions: - How is a DRSSTC designed and built? The DRSSTC system realized in this work is about 80 cm high and reaches about one-meter-long discharges. The design, development, and construction of the transformer are documented in detail and extensively in this thesis. - How does one measure an electrical voltage of 200,000 V, which changes sign more than 100,000 times per second? Two approaches have been taken to measure the voltages. Derived from the energy balance of an ideal capacitor and an ideal coil, a secondary voltage of about 200 kV was calculated via secondary current measurement. The second approach uses a voltage measurement via an in-house developed measuring electrode and a calculated divider ratio between the measured voltage and the secondary voltage. A relatively unrealistic secondary voltage of about 750 kV was measured since the divider ratio depends on approximate values. Nevertheless, the measuring electrode can be used for investigations of the voltage curve, or the divider ratio can be calibrated via the secondary current measurement. The development of such a transformer laid the foundation for much further research and scientific analysis.

車用開門快速預警裝置

由於台灣汽、機車數量逐年攀升,且人口密度高、道路窄小和停車位不足,使得人、車爭道和兩車併排等現象層出不窮,導致汽車駕駛人或乘客在開啟車門時,未注意後方來車造成碰撞的傷亡事故屢屢發生。有鑑於開啟車門不當事故頻繁,本研究提出一個基於達靈頓電路(Darlington Circuit)的快速且成本低之車門開啟預警系統,當汽車駕駛人或乘客碰觸車門內把手內側的軟式觸控薄膜開關時,系統即會啟動欲開啟車門側的門外警示燈和車後方向燈光閃爍,以提早預警行人或機車騎士,同時,汽車A柱內的警示燈、蜂鳴器會同步閃爍和鳴響,以提醒汽車駕駛人或乘客注意後方車輛避免碰撞,保障用路人安全。

沙墨乾渴、水山爆發-白板筆之創新設計

市售棉心式白板筆是以毛細現象將墨水儲存於棉心,當墨水過量會有漏墨問題或無法將墨水以毛細現象完全導出。本創新直液式白板筆是類似鋼筆方式儲水,其物理原理與舊型棉心式完全不同,它是以內外壓自然平衡來導引墨水,實驗中以棉心吸水效率、墨水損失率與色彩分析相關的實驗驗證下,其可改善舊式白板筆的缺點。但新式白板筆仍會受環境溫度與壓力變化而有漏水狀況。本組以自製測試設備輔助下,模擬了溫度對應壓力的變化、墨管內空氣與墨水膨脹率不同產生漏墨與高山大氣壓力降低導致墨水溢出的實驗。根據實驗結果本組進一步設計以針筒活塞來調整壓力的新式白板筆,完全解決了漏墨的缺點,且此環保可重複使用的設計是值得持續研究與推廣。

創新散熱系統-致冷晶片於電腦中的應用

1.手機及筆電已成不可或缺生活用品。但,若其充電器如果充電時間太久,可能會因為本身過熱而造成充電完畢要取回時,造成手部的燙傷。因為有此生活經驗,想改善充電器等高溫設備的散熱。 2.本研究探討電腦CPU上如果加上致冷晶片,如何加速散熱,增加使用安全外也進而提高電腦效能。 3.以電腦主機為實驗的操作器材,探究研發該散熱系統,並做為以後其他需要散熱的結構基礎,作為加速散熱的要件。目前致冷晶片在兩面溫差超越20°C時,可以使致冷晶片產生電能,接上微型馬達後,得以驅動,並產生對流散熱。 4.目前有關致冷晶片的實驗中,多數是使用致冷晶片和帕爾帖效應的關係,以通入電能使晶片兩面產生溫差。而本研究將採賽貝克效應做基礎,來探討新式散熱解決方案,使CPU產生的熱轉換成可以驅動微型馬達的電能。

研發奈米材料快速降解水中偶氮染料及其自動化循環系統

本研究為開發可適用於染整廠去除有機偶氮染料使用的自動化淨水設備,於設計設備前先探討奈米零價鐵(NZVI)去除化學染料效率,並針對不同操縱變因進行實驗,了解其化學反應性質。 在淨水設備的設計上,運用區域網路間Webduino Smart開發板、行動裝置、Webduino Blockly進行串聯,進行手動同步操作或自動化控制,使染整廠不僅降低人事成本及環境負擔,也避免染料外洩產生不可逆的環境嚴重汙染,同時節省染整過程使用的水資源。 操作部分選用Webduino Blockly來直接操控Webduino,使設備能在短時間內作動,避免第三方平台問題,也可提升設備的適地性。為了使染整廠能夠以最低成本達到類實驗室環境來處理廢水,特將模組與超音波清洗機調整成物聯網模式,以公式將光照度轉換為染料濃度,進而控制NZVI投加量並上傳雲端資料留存;超音波清洗機用以模擬超音波震盪機,使NZVI投加前均勻分散,發揮最佳降解效果。 本研究亦切合聯合國17項永續發展目標(SDGs)第六項:清潔飲水及衛生設施、第十二項:確保永續消費和生產模式。