Abstract

To improve the positioning accuracy of an inertial/geomagnetic integrated navigation algorithm, a combined navigation method based on matching strategy and hierarchical filtering is proposed. First, the PDA-ICCP geomagnetic matching algorithm is improved. On basis of evaluating the distribution of magnetic measurements, a number of controllable magnetic values are regenerated to participate in the geomagnetic matching algorithm (GMA). As a result, accuracy of the matching algorithm is ensured and its efficiency is improved. Secondly, the integrated navigation filter is designed based on the hierarchical filtering strategy, in which the navigation information of the geomagnetic matching module and inertial navigation module are respectively filtered and fused in the main filter. In this way, the shortcoming that GMA is unable to provide continuous and real-time navigation information is overcome. Meanwhile, precision of the inertial/geomagnetic integrated navigation algorithm is improved. Finally, the feasibility and validity of the proposed algorithm are verified by simulation and physical experiments. Compared with the integrated filtering algorithm which directly uses the error equation of inertial navigation system (INS) as the state equation, the proposed hierarchical filtering algorithm can achieve higher positioning precision.

Highlights

  • An inertial navigation system (INS) can provide continuous and real-time navigation information for the carrier, and it is characterized by strong autonomy and good concealment

  • The loose navigation algorithm mainly consists of the geomagnetic matching algorithm (GMA) and integrated navigation algorithm (INA), in which the locations evaluated by the GMA are used as observations of the integrated filter to estimate INS’s error [5]

  • Pk,i Pr00 ki i=1 where Pk is the final position estimated by the regeneration measurements (RMs)-Probability data association (PDA)-Iterated Closest Contour Point (ICCP) algorithm, Pk,i is the matching result of ICCP algorithm corresponding to the ith magnetic measurement mki

Read more

Summary

Introduction

An inertial navigation system (INS) can provide continuous and real-time navigation information for the carrier, and it is characterized by strong autonomy and good concealment. I=1 where d measures the distance of In and its corresponding contour line Cn. The ICCP algorithm assumes that the magnetic sensor has no measurement error, and the real position of the carrier is located on or very close to the magnetic contour that corresponds to the magnetic measurement [17]. Xiao combined the probability data association (PDA) algorithm with the ICCP algorithm [19,20] and proposed a PDA-ICCP algorithm It regarded all measurements of the magnetometer within a certain confidence range in interference environment as the effective measurements of a position, and evaluated the carrier’s location with the PDA fusion algorithm. To guarantee the accuracy of the integrated inertial/geomagnetic navigation under interference environment, the PDA-ICCP algorithm is improved in our study and on basis of it, a new integrated navigation filter is designed. The feasibility and effectiveness of the proposed algorithm are verified through simulation physical and experiments

RM-PDA-ICCP Geomagnetic Matching Algorithm
Calculation of mk0 and σ2
Constraints of Carrier’s Kinematic Performance
Constrains
3.3.Design
State Equation and Observation Equation of the Subsystem
State Equation and Observation Equation of the Main Filter
Integrated Filtering Algorithm
Filtering
Simulation Experiments
Effectiveness of the Proposed Algorithm
Filtering results of of thethe geomagnetic ofgeomagnetic geomagnetic
Algorithm Comparison
15. Filtering
Conclusions

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.