状态受限的小小型型无人直升机轨迹跟踪控制

Trajectory-tracking control for small unmanned helicopter with state constraints

无人直升机模型阶数比较高,设计常规反步控制器面临繁琐的对虚拟控制输入信号求导过程.针对此问题,设计了一种基于滤波器的反步控制方法.该方法通过滤波器而非直接解析地对虚拟控制量进行求导,从而显著简化了反步控制律的计算过程.在滤波器设计过程中,通过限制中间虚拟控制信号的幅值,变化速率以及带宽,以满足系统对状态变量及控制输入信号的约束要求.李雅普诺夫稳定性分析证明了直升机补偿跟踪误差全局指数稳定.仿真研究验证了该方法的有效性.

Because of the high order of the unmanned helicopter＇s model, it is very complicated and tedious to calculate derivatives of the virtual control signal in standard backstepping. This paper designs a filtering backstepping controller which uses a filter to calculate the derivatives of the virtual control signal, instead of using the analytical differentiation. Thus, it significantly simplifies the backstepping implementation. In the process of filter design, requirements on system states and control constraints can be satisfied by limiting the magnitude, rate and bandwidth of the virtual control sig- nals. The exponential stability of the compensated tracking errors is proved by using Lyapunov theory. Simulation results illustrate the efficacy of the proposed method.