Towards Improved UXO Discrimination in Shallow Water using Hypermag Rigidly Mounted on Uncrewed Surface Vessels (USVs)

Marine magnetic data acquisition for UXO survey has standardized to towed magnetometer arrays. However, towing magnetometers from an USV is operational difficult and has yet to see widespread adoption. Additionally, in shallow water less than five meters, towed surveys present other challenges due to survey vessel draft, and equipment and crew safety.

Hypermag is a scalable array of three-component magnetometers with compensation algorithms to allow for a rigid integration on the USV. During operations, the vehicle is directed through a compensation maneuver, generating compensation coefficients which can then be applied in real-time to produce compensated magnetic measurements that minimize the vehicle’s magnetic influence. Subsequently, the sensor data may be rotated from the sensor frame to a fixed frame of reference to obtain compensated three-component measurements.

Removing the background field to calculate the amplitude of each residual vector enables the interpretation of amplitude and direction maps of the residual vectors can be created. These maps can be used to characterize the location, shape, magnetization direction, and orientation of targets leading towards improved discrimination of UXO.

Results from Hypermag on a Maritime Robotics Otter USV are presented below.