基于动力学模型辅助的微小型飞行器新型解析冗余容错导航方法

Recently, the flight environment and the flight task of small aircraft become more and more complicated. It brings new challenges to the robust of navigation system. Due to low cost, small size and light weight, the analytical redundancy based fault tolerance navigation technique has been widely used by small aircrafts. However, the current technique is based on the assumption that there exists no fault in the reference system. The faults of the reference system are not covered. Therefore, there may have hidden risks when implementing the current tolerance navigation technique in small aircrafts..In order to solve the above problem, the construction of the new navigation redundancy and the improvement of the fault tolerance navigation will be studied in this project. A new navigation redundancy based on the dynamic model will be constructed for small aircrafts. The dynamic model/ inertial sensor/ measurement sensor fault tolerance navigation scheme will be proposed. A new filter framework for fault tolerance navigation will be constructed. The corresponding fault detection, isolation and system reconfiguration methods will be studied. The faults of all the sensors in the system will be covered in the new scheme. Through above research, the limitation of the fault diagnosis and system reconfiguration for the reference system fault should be broken. The theoretical method of the analytical redundancy based fault tolerance navigation method will be improved. This project will introduce a new idea for improving the navigation robust for small aircrafts.

近年来，微小型飞行器呈现飞行环境复杂化、飞行任务多样化的发展趋势，对导航系统可靠性带来了挑战。解析冗余容错导航凭借其成本低、体积小、重量轻的优势，是目前微小型飞行器常用的容错导航技术。然而，目前解析冗余容错导航方法基于“参考系统无故障”假设，无法实现针对参考系统故障的容错导航，为其在微小型飞行器中的应用带来了隐患。 .本项目针对上述问题，从新型冗余导航信息源构建、容错导航方法改进两方面开展研究工作：通过微小型飞行器的动力学模型，构建一种新型解析冗余导航信息源，形成动力学模型/惯性/量测传感器容错导航方案；建立无参考系统的解析式容错导航滤波构架，研究该滤波构架下的导航系统故障检测、隔离与重构方法，实现系统内各导航传感器故障下的全面容错导航。基于上述研究，突破解析式容错导航无法对参考系统进行故障诊断与重构的限制，完善解析式容错导航理论方法，为微小型飞行器高可靠性导航提供一种新的思路和方法。

微小型飞行器常用的导航传感器包括惯性传感器、全球定位系统、气压高度计、磁传感器等。受成本、体积等限制，微小型飞行器通常使用MEMS惯性传感器，由于其精度较差，通常需要卫星导航系统来辅助使用。在卫星信息丢失等复杂环境下导航系统的性能急剧下降，影响飞行安全，因此微小型飞行器导航系统的故障检测、隔离与系统重构，对于保障其飞行安全具有重要意义。项目将微小型飞行器动力学模型引入导航系统中，形成惯性传感器/动力学模型/量测传感器融合的解析式容错导航构架; 研究并提出单套惯性传感器配置下的故障诊断方法及惯性传感器故障后的导航系统重构方法，有效提高了微小型飞行器导航系统可靠性和稳定性; 构建了四旋翼飞行器试验验证平台，并分别针对惯性传感器、动力学模型、量测传感器故障类型设计了其验证方案。试验结果表明：项目提出的容错导航方案，可以实现在单套惯性传感器配置下对陀螺、加速度计、GPS、气压高度计、磁传感器的故障检测与隔离；当惯性传感器故障时，通过动力学模型的引入，可以有效提高导航系统精度；外界风的干扰可以被有效检测与隔离，从而避免了对现有机载导航系统的影响。