Jiang Jie, Yu Wenbo, Zhang Guangjun
Key Laboratory of Precision Opto-Mechatronics Technology, Ministry of Education, School of Instrumentation Science and Opto-Electronics Engineering, Beihang University, No. 37 Xueyuan Road, Haidian District, Beijing 100191, China.
Sensors (Basel). 2017 Oct 7;17(10):2285. doi: 10.3390/s17102285.
Navigation accuracy is one of the key performance indicators of an inertial navigation system (INS). Requirements for an accuracy assessment of an INS in a real work environment are exceedingly urgent because of enormous differences between real work and laboratory test environments. An attitude accuracy assessment of an INS based on the intensified high dynamic star tracker (IHDST) is particularly suitable for a real complex dynamic environment. However, the coupled systematic coordinate errors of an INS and the IHDST severely decrease the attitude assessment accuracy of an INS. Given that, a high-accuracy decoupling estimation method of the above systematic coordinate errors based on the constrained least squares (CLS) method is proposed in this paper. The reference frame of the IHDST is firstly converted to be consistent with that of the INS because their reference frames are completely different. Thereafter, the decoupling estimation model of the systematic coordinate errors is established and the CLS-based optimization method is utilized to estimate errors accurately. After compensating for error, the attitude accuracy of an INS can be assessed based on IHDST accurately. Both simulated experiments and real flight experiments of aircraft are conducted, and the experimental results demonstrate that the proposed method is effective and shows excellent performance for the attitude accuracy assessment of an INS in a real work environment.
导航精度是惯性导航系统（INS）的关键性能指标之一。由于实际工作环境与实验室测试环境存在巨大差异，在实际工作环境中对INS进行精度评估的需求极为迫切。基于增强型高动态星跟踪器（IHDST）的INS姿态精度评估特别适用于实际复杂动态环境。然而，INS与IHDST的耦合系统坐标误差严重降低了INS的姿态评估精度。鉴于此，本文提出了一种基于约束最小二乘法（CLS）的上述系统坐标误差高精度解耦估计方法。首先将IHDST的参考系转换为与INS的参考系一致，因为它们的参考系完全不同。此后，建立系统坐标误差的解耦估计模型，并利用基于CLS的优化方法精确估计误差。补偿误差后，可基于IHDST准确评估INS的姿态精度。进行了飞机的仿真实验和实际飞行实验，实验结果表明所提方法有效，在实际工作环境中对INS的姿态精度评估表现出优异性能。
