临近空间飞行器滑模控制中的指令参数化方法

Parametric Command Method in Sliding Mode Control for Near Space Vehicle

为了研究临近空间飞行器滑模控制方法,建立了临近空间飞行器无动力滑翔阶段的纵向运动模型,并应用动态逆方法证明模型是可逆的,且可实现绕质心运动模型的线性化.以动态逆控制为内环,滑模控制为外环,设计了飞行器纵向控制系统.从提高信息利用率和增加控制系统设计自由度的角度出发,提出俯仰角变化率指令参数化计算方法.仿真结果表明:纵向控制系统可以准确跟踪攻角指令,满足控制精度要求;俯仰角变化率指令参数主要影响控制系统的动态响应能力和稳态控制精度.

To study the sliding mode control method in attitude control of near space vehicle （NSV）, the un-power glide-phase motion of NSV was modeled by nonlinear longitudinal dynamic equations. The invertibility of the model was proved by dynamic inverse method. The rotation motion model can be linearized by feedback linearization. Dynamic inversion method and sliding mode control were used in inner-loop and outer-loop controller for designing longitudinal control system,respectively. The parametric command method, which can raise the utilization rate of information and increase the degree of freedom for designing control system, was proposed to improve the performance of control system. Simulation results demonstrate that the proposed controller tracks attack angle command accurately and meets the performance requirements with acceptable control inputs; the dynamic response characteristic and stability precision of control system are influenced by parametric command method markedly.