Survey Vessel Verification and Calibration Survey
During June and July 2017 GEOSIGTH Dimension Control surveyors completed verification surveys of the construction support vessels Voe Vanguard and Forth Warrior whilst the vessels lay alongside in Barrow Docks in Cumbria and of the vessel Atlantic Explorer alongside in Liverpool Docks.
The verification surveys initially consisted of determining a suitable vessel reference frame and subsequent sensor offsets with the vessel reference frame. Following this, a geodetic control network was established on the quayside, which GEOSIGHT surveyors were able to use in validating the accuracy of the installed vessel GNSS receivers by extending horizontal and vertical control onto the vessel using highly accurate Leica total stations. Finally, GEOSIGHT surveyors carried out alongside gyro calibrations using a baseline from the quayside control network and extending this onto the vessel to determine the misalignment angle between the gyro’s north and the local north of the coordinate system of the vessel.