导弹滚转通道气动伺服弹性稳定性分析

弹性飞行器可能由于结构、气动及控制的不利耦合引发气动伺服弹性失稳,为此分析了带有差动舵面及控制系统的细长体导弹滚转通道气动伺服弹性稳定性.导弹的广义非定常气动力采用气动导数方法计算,动力学方程考虑了弹体的刚体滚转运动和一阶弹性扭转振动.由导弹动力学方程求解得到滚转通道的开环传递函数,并应用Nyquist方法进行闭环系统稳定性分析.算例表明,若控制系统设计不当,系统有可能在弹性振动频率处发生气动伺服弹性失稳. 

Aeroservoelastic stability on roll loop of a missile

Flexible air vehicles may encounter aeroservoelastic instability which is induced by the adverse coupling between structure, aerodynamics and controllers. Aeroservoelastic stability on roll loop of a missile with differential rudders and control system is analyzed. The generalized unsteady aerodynamics is calculated by the aerodynamics derivative method which is based on the quasi-steady aerodynamics theories. And the rigid-body roll and the first elastic torsion mode of missile body are concerned in the equations of dynamics. The open-loop transfer function of the roll loop is solved from the equation of dynamics, and the aeroservoelastic stability of the system is analyzed by using the Nyquist method. The results of a missile show that, the closed-loop aeroservoelastic system may be unstable when encounters ill-suited control design. So the elastic modes and frequencies of missile body should not be overlooked in missile design.