Magnetic-Inertial Odometry Design Using Artificial AC Magnetic Fields in Outdoor Environment

Magnetic field vector measurement model derived from a simple geometric coil model has been widely reported. These field vector measurements can be used to estimate the pose of a vehicle at a high level of accuracy in real-time. In our previous work, we introduced a magnetic positioning system (MPS) using these magnetic field vector measurements and performed 2D pose estimation. In this paper, we first introduce the initial calibration of the magnetic field considering both the magnetic field measurements and theoretical models. Then, estimation of position, velocity, and attitude is performed by multi sensor fusion between calibrated MPS, odometer and INS. This is implemented in a tightly-coupled(TC) extended Kalman filter(EKF) structure. The results demonstrated precise three- dimensional navigation performance and the benefits of the tightly coupled structure, resulting in accurate navigation and robustness.