Gliders dead-reckon when underwater using pitch and heading measurements from an attitude sensor (among other things). To get the most accurate readings for these, we need to account for magnetic fields within the glider (e.g. from batteries or a thruster). To do this we hoist the glider up into our custom-made gyro frame (built by Brian Claus) and rotate the vehicle through all three axes of rotation. Special software builds up a point cloud from the resulting attitude observations, finds the best fit to them and outputs a calibration for the sensor.
Jack Foley in action rotating the glider
Here we're just testing out this technique. When doing a real calibration, the frame needs to be away from structures like cars and buildings, which have their own magnetic fields.
Photo credits: Robin Matthews
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