本論文主要針對不穩定無尾翼飛機之側向穩定控制進行設計，飛機之外型參考諾思洛普(Northnop)公司所研發的YB-49無尾翼飛機，研究過程中使用DATCOM軟體計算出飛機的氣動係數，並且根據DATCOM計算的結果發現其飛機穩定性明顯不足。
研究過程中，不使用傳統的根軌跡法，而使用可應用於多輸入多輸出的特徵根指定法，分別發展P與PID兩種控制設計，在側向線性化運動方程式中，拉氏轉換後得出不同階數的系統方程式，P控制為4階方程式，因此可指定4個特徵根；PID控制為8階方程式，但其中有2個特徵根為零，因此可指定6個特徵根。本論文主要以指定之特徵根分析P控制與PID控制所需之控制增益值，之後並以模擬顯示系統之穩定狀況與追尋控制之性能。

This thesis focuses on the lateral stability control design for an unsteady tailless aircraft. The aircraft configuration reference design is based on Northrop YB-49 which was developed by Northrop Corporation. The aerodynamic coefficients were determined by DATCOM software and the results show that the stability of the tailless aircraft is unsteady.
Instead of traditional root locus method, the eigenvalues assignment method suitable for multi-input multi-output (MIMO) systems is adopted for the analysis of two forms of control designs, P and PID. The equations of motion are linearized and Laplace transform is used to transform the linear differential equations into a set of algebraic equations. For P control, the differential equations are of the fourth order and therefore have four eigenvalues to be assigned. For PID control, the differential equations are of the eighth order and therefore have eight eigenvalues. However, since two of the eigenvalues are always zero, there are only six eigenvalues which can be assigned. This thesis primarily analyzes the gains for P and PID control designs by the eigenvalue assignment method. After the gains are determined, simulations are conducted for the flight control system to check if the response characteristics and tracking performances are satisfied.

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