为了实现无人机舵机工作状态的在线监测, 实时提供故障类型与故障程度, 设计了一种基于多模型参数估计的舵机故障诊断算法。首先描述了舵机各典型故障类型的动态特性, 并建立相应的故障模型。然后就各故障类型设计相应的故障状态观测器及参数估计器, 实时监测舵机运行状态, 在舵机出现故障时能够及时给出故障信息。同时设计多观测器切换机制, 以解决多个观测器的选取问题。仿真结果表明, 建立的故障模型能够很好地描述典型故障的动态特性, 多观测器切换机制能够及时准确地切换至最接近当前舵机状态的观测器, 给出最接近实际情况的故障信息。

An actuator failure diagnosis algorithm was designed based on multi-model parameter estimation to monitor the working state online and present the failure type as well as failure degree in real time.Firstly,the dynamic characteristics of the typical actuator failures were described and the corresponding models were built up for each one.Then some state observers and parameter estimators were designed for each kind of the representative failures to monitor the operating state of the actuators and present the failure information in time.A switching mechanism was used to choose the correct observer for the current failure.The simulation result shows that the failure models we established can describe the dynamic behavior of the fault actuator very well,and the switching scheme can switch to the right observer correctly in time to supply the most accurate failure information.