Engineers from MIT and Woods Hole Oceanographic Institution (WHOI) have come together to develop a new technology that will be able to provide the same accuracy as GPS. They will be developing this technology in the Arctic Ocean. The Arctic environment is changing rapidly. It is one of the top controlling components of our climate. ICEX stands for Ice exercise. It is conducted usually about 150 to 200 nautical miles north of Prudhoe Bay, Alaska, and the Beaufort Sea. The Arctic environment is one of the most challenging places to exist for human beings. Temperature ranges from -80 to -24 degrees C.
The scientists said that their main focus was to develop a technology that could give accurate information of the location within the Arctic ocean. Their technology has three main components. The first component is a device that measures the motion relative to the ice. The second component is the underwater vehicle which is transmitting a sound impulse out of the ocean. This sound impulse is received by the four receivers hanging from the ice surface. When they look at the relative travel times from the vehicle to these various receivers, they can make a computation of where the vehicle actually was when it sent the message. They let the vehicle include in the message where it thinks it was, then compute the actual location, take the difference between the two, and send it back down. Together with information about how much the ice is currently moving because it is measuring the relative motion to the ice. The third component is understanding the environment. For this, they are using their measurement of salinity temperature to identify where they should be in the water column to get the possible navigation information. And by putting those together they can get very accurate navigation solutions. A hole measuring 15 by 3 feet is dug in the ice. The underwater vehicle would be deployed from that hole.
Bradli Howard, a graduate student at, MIT/WHOI Joint program said, "It was crucial during those first few days to make sure that everything was working correctly. We were not going to send the vehicle out to do the autonomous portions unless we were absolutely sure that it's going to work correctly, as designed."
Henry Schmidt, the chief scientist said, "We started getting a little more courageous and we put a rope on it. And now we start running with a prop. We rin missions that are within a couple of hundred meters from the hydro-hole."
Schmidt said that they received information about the upcoming storm in two days. He said that it was a now or never situation to test the device. The next day they released the vehicle into the water feeling anxious about the possibility of losing it. The vehicle was working as expected. Everything was going on smoothly and under control. When the vehicle was on its way to the station, it suddenly stopped. The computer stated that there was a fault and it caused the tail cone to actually override and stop. The scientists were worried because losing the vehicle was an irreplaceable loss. They feared that the data that proved that their concept worked would have been lost. Although the vehicle had stopped moving, it was acoustically communicating with the modems, so the scientists were able to know exactly where the vehicle was. But there was not enough time for recovering it because of the storm.
After the storm, the ice had moved substantially. By mapping the vehicle's last position, the scientist drilled a hole and tie off that vehicle. They were able to pull out the vehicle successfully. They stated that they were happy to successfully conduct the experiment in five days.
