Don Walsh talk

Fun talk by Don Walsh of Bathyscaphe Trieste fame:
https://itunes.apple.com/ca/podcast/lecture-archive-don-walsh/id674825635?i=164350914&mt=2

Trinity Bay 2015

It was back to Trinity Bay today for another glider deployment. This time we'll be trying out novel ways to fly Slocum gliders. Thanks go to the crew of Belle of the Bay and also Jack Foley, who came out of retirement to help out.

As usual, we deployed the glider from a skiff

We couldn't have asked for better weather

Exit stage right pursued by a load of seagulls

 

Steaming back to Heart's Content

Photo credits: Robin Matthews

Attitude sensor calibration

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

Glider deployment toolkit

These tools of the glider trade each have an important use:

Pilot's cap: To shield out the sun and identify who's in charge

Binoculars: For spotting the glider at a distance

Satellite phone: For communicating with glider pilots back at mission HQ in St. John's

Pocket knife: To quickly cut away line when doing a tethered test dive and the line gets tangled or caught

iPad: To use an app we've developed for monitoring deployed gliders (uGlide)

GPS watch: To navigate to the glider's location

Chart: To identify bottom depths and hazardous bathymetric features