平流层飞艇气动参数辨识

进入21世纪以来，随着科技的飞速发展，世界上掀起了研究和开发平流层平台的热潮。飞艇作为平流层平台可以实现无线通信、空间观测、大气测量以及军事侦查等目的。本文首先将飞艇所受的气动力分成由于来流速度产生的定常气动力和飞艇转动引起的非定常气动力两部分，通过理论分析建立了飞艇的气动力模型，从而得到需要辨识的气动参数。其次建立了以浮心为原点的六自由度非线性动力学模型和一种基于混合遗传算法的气动力系数辨识方法——混合遗传算法（遗传算法＋单纯型法）与极大似然法相结合的方法，并利用该方法对飞艇的气动参数进行辨识。通过仿真结果验证了该方法实用性和有效性。最后通过对气动参数的准确值与辨识值的分析比较，得出各个参数对飞艇运动性能的影响情况。

Aerodynamic Parameter Identification for Stratosphere Airship

With the development of science and technology, many countries in the world have a strong interest in developing stratosphere airship platforms since 21 century. Stratosphere airship can be utilized as platform for telecommunication, space observation, atmosphere measure and military surveillance purposes.The aerodynamic forces of airship were divided into two parts:steady aerodynamic forces and unsteady aerodynamic forces. Based on the theory analysis, the aerodynamic model was built and the identification aerodynamic parameters were acquired. The six-DOF nonlinear dynamic model was built. A method of aerodynamic parameter identification based on the hybrid genetic algorithms (genetic algorithm+simplex method) was put forward through combining hybrid genetic algorithm with maximum likelihood method. The nonlinear aerodynamic parameter identification of airship using simulation data was carried out to verify the validity and feasibility of the formed method. The identification results are satisfactory, which show that the maximum likelihood method with hybrid genetic algorithm is effective for airship aerodynamic parameter identification. Through the comparison between real value of aerodynamic parameters and aerodynamic parameters value of identification, the effect of different aerodynamic parameters on motion capability of airship can be achieved.