可控飛行撞地(controlled flight into terrain)是指飛機可由飛行員正常控制，但因
為一些失誤而撞上地面、阻礙物或水面墜毀，在各類航空事故肇因當中也屬於大宗。
自 1970 年代以來，地形碰撞威脅的偵測與閃避系統開始發展，至今在飛航運輸等大
型飛行載具上已相當成熟，而本論文的研究主題則針對小型飛行器動態變化較大、
速度較快的狀況，發展一適用於高動態飛行器的地障閃避系統。本研究發展的地障
閃避系統將以飛行器當下的動態，選用符合其動態的運動模型，預測其未來可能的
路徑，並以預測出的飛行路徑做為基準，根據飛機當下的動態決定出偵測的範圍，
並以該範圍對周遭地形進行比對，由此判斷有無碰撞的可能與進行閃避與否，若需
閃避則根據飛行動態提供相對應的垂直閃避路徑。本研究將使用飛行模擬軟體模擬
高動態下的飛行資料與台灣本島的地形資料，模擬在高動態下的可控飛行撞地，並
以該模擬情境測試本研究之地障閃避系統在飛機即將與地障產生碰撞的情況下，能
否及時偵測到地障，並提供安全的閃避路徑，最後分析閃避路徑所能夠閃避的高度
與執行閃避路徑所需的時間，由此確認本研究之地障閃避系統的可行性。

The objective of this thesis is to develop a terrain-clearance system that can be utilized for high dynamic flight vehicle. Thus, the concept of the ground proximity warning system for civil aviation is applied as a basis and its algorithm is modified to fit the high dynamic flight situation, including the use of the forward looking terrain avoidance (FLTA) method, the selection of avoidance maneuver as well as the detection envelope settings. The developed terrain-clearance system calculates a detection envelope by using the predict flight trajectory, and then compares the envelope with the corresponding terrain database to detect the possible collision threats. To evaluate the developed terrain-clearance system,
several rugged topographies and high dynamic flight situations are applied in simulation. Importantly, the simulation results show that the developed system can help the high dynamic flight vehicles to prevent any possible collisions with terrains.

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