Magnetic Field Measurement Method Based on Remotely Operated Vehicle

The existing magnetic field measurement method of a ship has the problems of low measurement flexibility and poor maneuverability. To address these problems, this study proposes a method for measuring the magnetic field of ships based on an underwater remotely operated vehicle (ROV). In this study, an overall integration scheme of the ROV magnetic measurement system is designed. That is, the ROV module, magnetic measurement module, and acoustic positioning module are integrated into one system. The magnetic measurement module uses two magnetic field sensors to measure simultaneously for improved measurement accuracy. In order to achieve precise positioning of the ROV, a multi-point underwater acoustic positioning method is adopted. The software of the ROV magnetic measurement system is designed and debugged, including receiving magnetic field information and acoustic information, calculating the ROV position, and storing measurement data. Finally, an iron platform with electromagnetic coils is used to simulate a surface ship to test the designed ROV magnetism measurement system in water. Before and after the electromagnetic coil on the platform is energized, the characteristics of the total magnetic field of the platform’s keel obtained via the measurement had the same changing trend. The measurement error of the Z-component magnetic field measurement value of the electromagnetic coil relative to the theoretical value is 5.66%, which indicates that the ROV magnetic field measurement system proposed in this paper has high reliability in the magnetic field measurement of the surface ship.