【摘 要】
：
针对火星探测器进入飞行弹道的高马赫数、化学非平衡效应和低动压等特点,提出了一种基于火星进入大气数据系统/惯性测量单元(MEADS/IMU)耦合的测量方法,实现海拔60 km以下区域的火星大气数据测量.利用自主研发CACFD软件平台的化学非平衡模型/完全气体模型计算获得探测器宽速域飞行流场的表面压力点数据,建立了基于BP神经网络的MEADS算法模型.在高马赫数段(Ma＞12)利用IMU测量获得的马赫数作为输入条件,结合MEADS算法测量获得总压、动压、静压、攻角和侧滑角等飞行大气参数,成功克服了马赫数无关性
【机 构】
：
中国航天空气动力技术研究院,北京 100074;北京空间飞行器总体设计部,北京 100094
论文部分内容阅读
针对火星探测器进入飞行弹道的高马赫数、化学非平衡效应和低动压等特点,提出了一种基于火星进入大气数据系统/惯性测量单元(MEADS/IMU)耦合的测量方法,实现海拔60 km以下区域的火星大气数据测量.利用自主研发CACFD软件平台的化学非平衡模型/完全气体模型计算获得探测器宽速域飞行流场的表面压力点数据,建立了基于BP神经网络的MEADS算法模型.在高马赫数段(Ma＞12)利用IMU测量获得的马赫数作为输入条件,结合MEADS算法测量获得总压、动压、静压、攻角和侧滑角等飞行大气参数,成功克服了马赫数无关性对MEADS系统测量的影响.在低马赫数段(Ma≤12),直接应用MEADS算法测量静压、马赫数、攻角和侧滑角.测试结果表明在MEADS系统测压单元误差≤7 Pa的条件:总压测量误差≤14 Pa(1.5％),攻角测量误差≤0.9°,侧滑角测量误差≤0.9°,动压测量误差≤10 Pa(1.5％),静压测量误差≤7 Pa(3％),马赫数测量误差≤0.1.飞行试验数据得出:MEADS测量与IMU测量马赫数、攻角和侧滑角等结果基本一致.
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