A New In-Flight Alignment Method with an Application to the Low-Cost SINS/GPS Integrated Navigation System

Sensors

Zhenglong Lu¹  Jing Mi¹  Jie Li¹  Kaiqiang Feng¹  Xiaokai Wei¹  Yang Liu¹  Debiao Zhang¹  Xi Zhang² 

[1] National Key Laboratory for Electronic Measurement Technology, North University of China, Taiyuan 030051, China;School of Electrical Control Engineering, North University of China, Taiyuan 030051, China;

关键词: in-flight alignment;    integrated navigation system;    optimization-based alignment;   

DOI  :  10.3390/s20020512

来源: DOAJ

【 摘 要 】

The optimization-based alignment (OBA) methods, which are implemented by the optimal attitude estimation using vector observations—also called double-vectors—have proven to be effective at solving the in-flight alignment (IFA) problem. However, the traditional OBA methods are not applicable for the low-cost strap-down inertial navigation system (SINS) since the error of double-vectors will be accumulated over time due to the substantial drift of micro-electronic- mechanical system (MEMS) gyroscope. Moreover, the existing optimal estimation method is subject to a large computation burden, which results in a low alignment speed. To address these issues, in this article we propose a new fast IFA method based on modified double-vectors construction and the gradient descent method. To be specific, the modified construction method is implemented by reducing the integration interval and identifying the gyroscope bias during the construction procedure, which improves the accuracy of double-vectors and IFA; the gradient descent scheme is adopted to estimate the optimal attitude of alignment without complex matrix operation, which results in the improvement of alignment speed. The effect of different sizes of mini-batch on the performance of the gradient descent method is also discussed. Extensive simulations and vehicle experiments demonstrate that the proposed method has better accuracy and faster alignment speed than the related traditional methods for the low-cost SINS/global positioning system (GPS) integrated navigation system

【 授权许可】

Unknown