极大似然法及在有控飞行器气动参数辨识中的应用

 <正> 一、引言 飞行器气动参数辨识作为系统辨识理论在航空、宇航领域的应用分支,在一些发达国 家受到了相当的重视,并且从70年代以来已形成了气动参数辨识软件包,不仅缩短了飞行器的设计、改型及性能分析的周期,并且还具有靠风洞实验或理论分析所不具备的优点。目前飞行器的气动参数辨识虽已有很大发展,但是对有控飞行器的闭环辨识问题仍未解决,分析传感器非线性因素对气动参数辨识结果的影响也不够深入。本文使用极大似然法,结合某有控飞行器的全弹道仿真数据,研究了在闭环飞行状态下进行气动参数辨识所存在的问题,分析了传感器的非线性因素对气动参数辨识的影响。

MAXIMUM LIKELIHOOD ALGORITHM AND ITS APPLICAITON TO PARAMETERS IDENTIFICATION OF THE CLOSED-LOOP FLIGHT VEHICLES

The maximum likelihood algorithm is used to estimate the aerodynamic coefficients of the closed-loop flight vehicles. Based on the dynamic model of aircraft, using the differential smooth technique, the linear estimation formula of aerodynamic parameters is given. For the closed-loop flight vehicles, determination of aerodynamic model and the effect of nonlinearity of sensors on the accuracy of identification of aerodynamic coefficients are investigated. Finally, some considerations for the aerodynamic parameters estimation in the case of closed-loop flight are given by the estimation results of aerodynamic coefficients from the 6DOF simulated data of a closed-loop vehicle.