14. Nov. 9, 1998, Monday: Patriot Hills Camp
The wind was still coming in gusts this morning, and the kitchen tent was all but deserted at our regular 9:30 breakfast time. I had a conversation with Stewart Moorehead about his obstacle detection system for Nomad. One component of this system consists of a set of stereo cameras for visual sightings that can be used by a remote observer, but also can be used by Nomad in its electronic nerve system to generate a 3-D map of objects in its path, which enables it to avoid them autonomously. He is finding that the stereo cameras, which need heaters to enable them to work at these temperatures, are misting up inside because of water condensation. This water freezes when the heat is turned off. The other component of his system is an infra-red laser that measures the distance to objects large enough to reflect its beam. He finds that when there is blowing snow, or falling snow, the beam tends to be scattered, either in the transmission or the reflected mode, and thus becomes much less efficient at locating objects ahead. Reflecting on this experience, he feels that the solution may be millimeter wave radar, which would not see the snowflakes but would see objects larger in diameter than its own wavelength.
This afternoon Stewart gave Danilo a comprehensive rundown on the history of Nomad: how it was built in haste and had only three days for testing before being shipped off to the Atacama Desert to show its stuff. Unfortunately, its "stuff" often involved breakdowns whose probabilities had not been anticipated by the inadequate testing program. It was also built by committee, with no oversight from anyone who had veto power over the computer codes that were used. Then, various of the designers left for other pursuits and those who took over were left trying to use codes with very few helping notes and certainly no comprehensive handbooks. So the result is a test bed for experiments; not an integrated robot.
Speaking of experiments, Liam's spectroscopy equipment was camping out with us at Pirrit Hills but it was too cold to use it there. Somewhere during transport out there and the return trip, something happened and it is not currently running, so cannot be immediately mounted on the robot. The windy weather today is also prohibitive, because the pod must be opened to insert the equipment.
Plans for deployment of Nomad have changed also. Rather than move the entire camp out to the valley on the other side of Patriot Hills, Nomad will be sent, along with a couple of small Expedition 25 tents, 2 or 3 people, and a larger tent that was bought to be an instrument tent while Nomad was in the valley. The significance of this to me is profound: I am living in the large Endurance tent, and it will remain in the Chilean camp. I can make periodic visits to the test site, but will have a comfortable place to sleep every night, unless, of course, I am caught there overnight by a sudden change in the weather. This plan should save a lot of time: it would take several days at least to move the entire camp, and this would be doubled, since it would all have to be brought back again.
Matt and Mike have gone over to Windy Pass to check on the Inmarsat antenna, which failed soon after a successful trial a few days ago. They found the antenna intact, but needing adjustment -- it had lost its orientation relative to the satellite constellation.
Alex, Stewart and Pascal are busy putting in the new field camp in the valley, and are now in continuous radio communication via the antenna at Windy Pass.