Vehicle attitude detection in underwater magnetic anomaly localization experiment

The relative position between magnetic target and the device installed on underwater vehicle, is determined by measuring magnetic field magnitude and gradients of target on condition that geomagnetic field anomaly can be viewed as a magnetic dipole target. The relationship between the errors of magnetic field magnitude, gradients and the variation of platform attitude and its effect on localization precision of vehicle are studied theoretically and simulated numerically. The results show that the effect of vehicle attitude variation on magnetic field magnitude and gradients are small and obvious, respectively. However, the distance between magnetic target and the device is not nearly varied. A new method calculating vehicle attitude variation by magnetic moments of the target is studied theoretically and simulated numerically. The results show the calculating precision for the novel method is higher in principle, which can be used to detect the attitude of underwater vehicle.