虛擬實境飛行模擬系統之PIO現象探討

Abstract

當飛機的功能越來越強大，系統日趨複雜，飛行訓練已無法像過去傳統般以實機來進行，利用模擬飛行器的重要性在於可減少潛在危險避免不必要的損害，因此對模擬系統開發和虛擬實境技術的需求日漸加重。近年來飛機事故頻傳，愈來愈多研究在於人機耦合現象（Aircraft-Pilot Coupling）方面。本論文首先介紹飛行控制系統，並探討真實飛機上的搖桿與飛機運動之間的操控關係，分為機械鏈結（Mechanical linkage）及線傳飛控（Fly-By-Wire）兩種系統，接著介紹自製兩軸力回饋搖桿，進行系統分析及模擬，並對搖桿推導其數學模型，在實驗部分方面，主要研究人機耦合現象之飛行員誘發振盪（Pilot-Induced Oscillation, PIO），飛行員誘發振盪現象會導致系統不穩定，甚至引起災難，其中傳動裝置的速率限制元件為導致飛行員誘發振盪的原因之一，本論文利用開路系統開始點準則（Open-Loop Onset Point, OLOP）作為分析PIO的工具，探討速率限制對PIO的影響，並利用自製力回饋搖桿來呈現此現象。由實驗結果得知，此力回饋搖桿確實可提供使用者擬真的力覺感受，而且能有效率地與飛行模擬系統溝通。

Nowadays, due to the cost and complexity, on-site aircraft flight training is improbable, if not impossible. Instead of real aircrafts, pilot training with a fight simulator not only avoids unnecessary costs but also decreases potential dangers. Hence, people pay much more attention to the development of flight simulation and virtual reality technique. In this thesis, the aircraft flight control system is first introduced and then the mechanical linkage and fly-by-wire control systems. In our laboratory we develop a 2-DOF force-reflection joystick and also analyze its mathematical model. The phenomenon of aircraft-pilot coupling（APC）is studied and the pilot-induced oscillation（PIO）discussed. Pilot-induced oscillation is resulting from aircraft-pilot dynamic coupling, which leads to instability. The actuator rate limiting has been a causal or contributing factor for PIO, and we apply the open-loop onset point（OLOP）technique for PIO prediction. Experiments based on using the developed force-reflection joystick are performed to demonstrate the PIO phenomenon.