「圖形板」的圖形軌跡之探討及其延伸
Starting from the problem in AMC competition of Australia, we try to find out the locus and its length when a point in a regular polygon rolls in a circle. The result is that the locus has a wonderful and regular cycle.Next, we discuss the regularity of the cycle when a regular polygon(n sides) rolls in another regular polygon. Furthermore,we discuss the the equation of the locus by changing the radius and the angle of rolling. we find out the argument function of the locus of a point inside when a a regular polygon(n sides)rolls in another regular polygon (m sides): , Aj is the summits of the regular polygon(m sides), Bjcorresponds Aj when a point inside the regular polygon (n sides) rolls, ) And then, we do some moving simulation with some computer math software, such as Cabri Geometry、Mupad, etc. We discuss the regularity of the locus and its equation of a point inside when some special cycloids, like asteroids, cardioids, etc, roll in a certain condition. Moreover, with the result of research 2, we create the “plate" and apply for a patent on it. We hope to study math by playing games.
從澳洲AMC 競賽題出發,嘗試探討一正n 邊形中的一點在單位圓內滾動軌跡及其軌跡長度,發現該軌跡均會產生奇妙的循環規律。
接下來,推廣探討正n 邊形在其他正多邊形中滾動時循環的規律,並利用旋轉半徑及角度之間的變化深入探討其滾動軌跡方程式,發現正n 邊形繞正m 邊形滾動時其內部一點軌跡參數式為,其中, Aj 為 正m 邊形之各頂點、Bj 為正n 邊形中內部一點旋轉時對應 Aj 之點,。
進一步想嘗試使用數學電腦軟體如:Cabri Geometry、Mupad 等對以上研究去做一些動態模擬,並再探討一些特殊擺線如:星狀線、心臟線…等,在條件下相切滾動時,圖中某一點的軌跡規律性及其方程式。另外,應用研究二中的結果,創造出寓數學於遊戲的「圖形板」,並申請了新型專利。
金屬的盔甲
Our aim to attend this science fair is to design an instrument that can plat and measure the mass at the same time. In hope of designing a simple, accurate and convenient apparatus, we created an electronic circuit to display our original idea. In the process of constant improvements, we finally accomplished a “Super Mass Plating Gauge”, which can be easily and widely utilized in school teaching. The production of microbalance and the arrangement of electric circuit are the most significant parts in our research. The major components of the “Super Mass Plating Gauge” include a straw, metal clips and our creativity—the well-arranged electric circuit. The idea of microbalance originated from the Internet, but we advanced it by numerous experiments. First, we attached a steel cord to one side of the cathode in the electricity supplier. Next, we fixed the other side to the negative plate. And then, on the end of the negative plate, we tied a metal clip with the metal that will be plated. Eventually a new “plating gauge” was invented. By doing so, we could use this instrument to make our experiments. Our experimental goal is to research how different kinds of metal, time, electrode and voltage can affect the reduced mass on the cathode. We made use of such metal as copper, zinc and silver to carry out the experiments. In the end, by analyzing the results, we concluded a plating formula that can be applied to metal plating.
我們做此科展的目的,是要設計一個可以邊電鍍、邊測量質量的儀器,我們希望這個儀器是簡便、精確、且線路簡單,並且能推廣到教學的器材。經過我們不斷改良,終於完成了「便利質量電鍍器」 。 其中製作微量天秤和線路的配置方法,是本研究的重要部分。微量天秤的主要結構是吸管、鱷魚夾、及線路。微量天秤的構想,是參考以前的科展作品並加以改良,可精準測量到0.00010g,而裡面的線路,則是我們的創意(如圖一) 。只要把電源供應器的正極,接上左右任一鋼條,負極接到容器另一端,並加上一個鱷魚夾,夾上被鍍物,便是一個可邊電鍍,邊測量質量的儀器了!如此一來,我們就能以此儀器來作我們以下的實驗。 我們實驗目的在探討電鍍時不同金屬、不同時間、電極大小及電壓,對正極金屬片所減少質量的影響。 最後,我們推導出一個有關電鍍時正極金屬片質量變化量的實驗公式。為此,我們也要做許多次、許多種的實驗,來驗證我們的公式是否正確,並以我們所學的理論來推論。
滑鼠狂想曲
光學滑鼠會以很高的速度不斷地對著接觸面拍照,藉由比對每幅影像間的變化來偵測滑鼠移動的速度與方向,本研究利用此特點而設計一個簡易的光學量測系統,其中包括透鏡、光源與接觸面材質的選擇,以及利用Raw Input 模式讀取個別滑鼠移動訊息而發展出來的量測程式,使得此系統可以在無接觸與無摩擦的情況下來測量外界物體的移動速度與距離,經由實驗證明,在光學感測器還可以感應與追蹤的範圍內,量測的數據還蠻精準的。接觸面到光學感測器透鏡的距離越遠,能夠測得移動物體的極速也越高,但是會造成感測器的解析度下降,如此限制了接觸面的材質種類,無法量測表面較為光滑的物體,但是在設計得宜的情況下,仍有蠻多方面的用途,日後若能採用較高效能的光學感測器並加上測距儀的輔助,相信此系統的應用層面會更為廣泛。Optical mouse can take continuous snapshots very quickly of the contact surface and compare the images sequentially to detect the direction and amount of movement. This study uses this feature to design a simple optical measurement system, including lens, illumination and contact surface choice, as well as the measurement program using raw input model to accept the movement information from the mouse. This system can measure the distance and speed of the motion object under the non-friction condition. From the experiment test result, this optical measurement system is workable and satisfactory. Contact surface to optical sensor distance farther, can measure the higher speed of the motion object, but will cause the lower resolution of the optical sensor. This will limit the variety of the contact surface; superficial smoother object is unable to measure. In the future if we can use the high performance optical sensor and assist with rangefinder, believed this system can have more widespread applications.