采用图形法建立了导弹线性分式变换(LFT)模型,将导弹动力学明确描述为确定性与不确定性两部分,构造了线性参数时变(LPV)/μ控制结构,运用D—K—D迭代算法设计了导弹H∞增益调度自动驾驶仪。LPV/μ控制技术明确考虑了导弹的时变特性,设计生成的控制器能够在导弹飞行过程中自动进行参数调节,适应导弹动力学特性的变化,从而稳定自动驾驶仪的动力学特性。仿真结果表明:建立的线性分式变换模型能够准确描述导弹的动力学特性,同时所设计的H∞增益调度自动驾驶仪的动力学特性基本与导弹飞行条件的变化无关。
The missile linear fractional transformation(LFT) model was established by the graph approach, and the missile's dynamics was separated into certainty part and uncertainty part. Based on the LFT model, the linear parameter varying (LPV)/μ control structure was established, and the H∞ gain-scheduled autopilot was designed by use of D-K-D iteration. The designed controller with the LPV/μ technique, which takes account of the time-varying nature of missile explicitly, can automatically gain-schedule the parameters in the course of missile flight, adapt to the variation of the missile dynamics characteristics, and stabilize'autopilot dynamics characteristics over its entire operation range. Simulation results show that the LFT model can describe the missile's dynamics exactly, and the dynamics of H∞ gain-scheduled autopilot are independent of the flight conditions.