title: Modeling and Implementation of Multi-Position Non-Continuous Rotation Gyroscope North Finder.
abstract: Even when the Global Positioning System (GPS) signal is blocked, a rate gyroscope (gyro) north finder is capable of providing the required azimuth reference information to a certain extent. In order to measure the azimuth between the observer and the north direction very accurately, we propose a multi-position non-continuous rotation gyro north finding scheme. Our new generalized mathematical model analyzes the elements that affect the azimuth measurement precision and can thus provide high precision azimuth reference information. Based on the gyro's principle of detecting a projection of the earth rotation rate on its sensitive axis and the proposed north finding scheme, we are able to deduct an accurate mathematical model of the gyro outputs against azimuth with the gyro and shaft misalignments. Combining the gyro outputs model and the theory of propagation of uncertainty, some approaches to optimize north finding are provided, including reducing the gyro bias error, constraining the gyro random error, increasing the number of rotation points, improving rotation angle measurement precision, decreasing the gyro and the shaft misalignment angles. According them, a north finder setup is built and the azimuth uncertainty of 18" is obtained. This paper provides systematic theory for analyzing the details of the gyro north finder scheme from simulation to implementation. The proposed theory can guide both applied researchers in academia and advanced practitioners in industry for designing high precision robust north finder based on different types of rate gyroscopes.
authors.affiliation: Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. luojun604@sina.com.|University of the Chinese Academy of Sciences, Beijing 10049, China. luojun604@sina.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Luo
authors.affiliation: Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. wangzhiqian@ciomp.ac.cn.
authors.forename: Zhiqian
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. shenchengwu@ciomp.ac.com.|University of the Chinese Academy of Sciences, Beijing 10049, China. shenchengwu@ciomp.ac.com.
authors.forename: Chengwu
authors.initials: C
authors.lastname: Shen
authors.affiliation: Fraunhofer Institute for Computer Graphics Research, Darmstadt 64283, Germany. arjan.kuijper@igd.fraunhofer.de.|Mathematical and Applied Visual Computing, Technische Universität Darmstadt, Darmstadt 64283, Germany. arjan.kuijper@igd.fraunhofer.de.
authors.forename: Arjan
authors.initials: A
authors.lastname: Kuijper
authors.affiliation: Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. wenzhuoman@gmail.com.|University of the Chinese Academy of Sciences, Beijing 10049, China. wenzhuoman@gmail.com.
authors.forename: Zhuoman
authors.initials: Z
authors.lastname: Wen
authors.affiliation: Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. evsv@sohu.com.
authors.forename: Shaojin
authors.initials: S
authors.lastname: Liu
keywords: azimuth; gyro misalignment; north finding; orientation; shaft misalignment; uncertainty analysis