本論文研究並設計ㄧ個三軸之低成本的電子式飛機失事感測器。此失事感測器的主要功能為持續地監視飛機飛行狀態，並在飛機失事之瞬間，自動送出警示信號給緊急定位信號發射器，發送飛機位置訊號，以縮短搜索失事殘骸的時間。本失事感測器之核心為微機電加速儀，利用PIC單晶片微控制器負責執行加速度信號擷取、分析及啟動警示命令等動作。 失事條件判斷乃利用加速儀量測之加速度信號和計算速度變化率來決定警示之時機。為保證系統的穩定工作，本失事感測器也包含了鋰電池之備用電源，以確保在飛機失去電源時，系統仍可持續正常的工作。此外，為了解飛機失事時，加速度信號之特性，特別設計了一個失事感測器之落地實驗，並成功地執行了驗證工作，以協助了解落地瞬間之加速度特性及速度變化情況。本研究已成功的設計包含軟、硬體整合之三軸電子式飛機失事感測器，並完成實驗室功能展示。 This research develops a low cost three-axis electronic crash sensor for airborne application. The key elements of the crash sensor are two dual-axis MEMS technology based micro accelerometers. The crash sensor continuously monitors the acceleration of the air vehicle. An emergency activation signal will be engaged to activate the Emergency Locator Transmitter once a real crash is assured. In the design, the crash accident is assured if the acceleration exceeds 2.3 G and the velocity variation exceeds 1.4 m/sec. The data acquisition, reduction, crash condition determination, and beacon order activation are accomplished through a low cost microcontroller. A rechargeable Li-ion battery is incorporated as a backup power source. In order to gain more understanding of the crash signal characteristics, a drop test is developed and successfully conducted in the lab.
