航空攝影的技術已經普遍應用在不論是軍事還是民生用途上。在台灣這種天災頻傳的環境中，這樣的技術更是重要。不論是颱風還是地震都會造成地貌大幅度的轉變。要能夠迅速的掌握災情，主要還是依靠衛星影像和航空拍攝影技術。但由於衛星影像成本太高且受天氣影響程度高於航空攝影，所以現在台灣在天災的救援技術來說還是以航空攝影為主。另一方面，由於受到台灣攝影師齊柏林先生所拍攝的電影“看見台灣”的啟發，台灣現在有越來越多人開始從事航空攝影，希望能夠從多種不同的視角欣賞台灣之美。以目前的技術來說，航空攝影活動需要有人隨時監控才能準確的達成任務。本研究主要是建構一套低成本且能穩定自動追蹤已知目標的攝影系統。整套系統不包含攝影機總共不到1000USD，但是卻有一定程度的追蹤性能。
本研究主要方向是應用GPS和AHRS系統為參考資料經過坐標轉換演算後由MCU輸出PWM訊號來控制無刷馬達攝影雲台，進而達成定點追蹤目標的功能。GPS訊號從接收器接收以後藉由坐標變換與UTM地圖投影轉換成為直觀的卡氏坐標系來描述坐標。AHRS方面則是透過整合MEMS系統包含IMU和磁力計來實現。在姿態演算法方面則是採用四元數來敘述姿態，並且由數值分析方法來更新。Mahony 濾波器則是用來防止姿態飄移。最後整合位置與姿態資訊透過坐標轉換公式推導出瞄準角度，硬體上藉由MCU輸出對應的PWM訊號來驅動雲台達成定點攝影並且藉由圖傳系統及時的把影像回傳至地面站，讓地面人員得以監控目標。本研究經由輕航機來做實測，在實驗中追蹤演算法的可行性得到驗證。

Aerial photography technique has been used in widespread fields, no matter for military or for civil purpose. It means a lot especially to Taiwan region striking by many kinds of natural disaster annually. Two of most frequently happened natural disaster are hurricane and earthquake that can cause significant change of earth feature. To get better and quicker understanding about damage after disaster happened, satellite and aerial image is used. But satellite is too expensive to afford, and it is more likely to be affected by cloud. Hence, aerial image is the mainly used to assist rescue efforts. On the other hand, being inspired by movies “Beyond Beauty - Taiwan From Above” which directed by Po-lin Chi, more and more people dedicate themselves in aerial photography. In terms of today's technology, operator is needed to accomplish mission precisely.
An automatic static target tracking system which cost less than a thousand dollars (USD) is built in this study. Using GPS and AHRS data, angles supposed to turn can be calculated, and corresponding PWM signal drives gimbal to accomplish static target tracking. Message form GPS receiver can be transferred to Cartesian by UTM. MENS including IMU and magnetometer is used to implement AHRS. Quaternions are introduced to describe attitude and updated using first order Runge Kutta equation. Mahony filter, on the other hand, is the method chosen to prevent data drifts in attitude. By integrating positional information and attitude data together, desired angle can be obtained. The method is verified in the experiment part.

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