攔截飛彈的姿態控制

Abstract

本論文探討攔截飛彈姿態控制系統的設計與分析，數值模擬參考標準飛彈三型為藍本。姿態控制的目的是要使攔截飛彈的尋標器在終端導引階段一直追蹤目標。姿態控制的制動器是常值開關式的推力器。我們探討兩種控制方法：線性控制系統配合脈衝寬度調變(pulse width modulation, PWM)的合成以及最短時間最佳控制系統(minimum-time optimal control)，線性控制器部分主要討論脈衝寬度調變的頻率設定，最短時間最佳控制則透過修改切換曲線及控制律來降低至動器的切換頻率。控制系統的性能必須透過完整的六自由度模擬來驗證，模擬結果顯示如果適當的選擇設計參數，線性控制系統配合脈衝寬度調變以及最短時間最佳控制系統均可有效地達到控制目標。最後我們加入質心偏移的影響來分析兩種控制系統的性能表現。

This paper studies the design and analysis of attitude control system for a missile interceptor. Simulations use Standard Missile III as a prototype. The goal of attitude control is to ensure that the infrared seeker of the interceptor tracks the target in the terminal guidance phase. The control system employs constant value ON-OFF thruster as actuators. We investigate two design methods: linear control system with pulse-width modulation (PWM) implementation and minimum-time optimal control system. For the linear control system, we focus on how to choose a proper PWM frequency. In order to reduce the switching frequency of the minimum-time optimal control system, we modify the switching curve and the control law. Simulation result indicate that with proper choices of design parameters, linear control system with PWM and minimum-time optimal control system both can achieve design goal. Finally, we analyze the performance of two type control system by considering the effect of the g.c. offset.