In September 2014, ESA astronaut Andreas Mogensen and ESA astronaut trainer and spacewalk instructor Hervé Stevenin joined an international crew for a seven-day underwater mission for NEEMO NASA Extreme Environment Mission Operations.
NEEMOs underwater habitat off Florida acts as makeshift a space base for astronauts to make regular waterwalks in full scuba gear. Both underwater missions plan sorties for the astronauts to simulate spacewalks.
Their mission focused on wearable computers and remotely monitoring the crew. An ESA voice-command mobiPV prototype using smartphones, tablets and screen glasses was tested. This approach was later used on Andreas space mission in September 2015.
Connect with Andreas: http://andreasmogensen.esa.int
More about NEEMO: https://www.nasa.gov/mission_pages/NEEMO/index.html