考虑饱和的舵机自适应控制系统

An Adaptive Control Scheme for the Rudder System with Saturation

针对某飞行器舵机系统中饱和非线性造成的不良影响，研究了一种模型参考自适应控制方案后，对舵机系统进行了自适应改进设计，并将其应用于此飞行器纵向控制系统中。仿真结果表明，这种自适应舵机系统不仅能提高飞行性能。

The deflection speed saturation of rudder in a standard feedback rudder system (Fig.1) causes deterioration of flight performance. We use a model reference adaptive control scheme to overcome it. In section 1, we use Wang′s adaptive control scheme [2] as shown in Fig.2. Then we derive the reference model (eq.3) according to the model of the rudder system as shown in Fig.1. After a lengthy derivation involving eqs.(4) through (13), we get the tracing error (eq.13) of the adaptive rudder system with saturation. To our best knowledge, we did not find anything like eq.(13) in the open literatures. Based on the tracing error, we get eq.(21) as the adjusting rule for θ 1,θ 2,θ 3. Fig.3 gives the simulation results. The dotted curve shows the height variation with time when we use the adaptive scheme to control the rudder system with deflection speed saturation of 30°/s. The solid curve shows that of a classical rudder system when the saturation is 50.5°/s. It shows that our adaptive control scheme can prevent the vehicle from dropping steeply during climbing up even when the saturation is as low as 30°/s. Our adaptive control scheme is robust and easy to implement.