Sailing Robots To Attempt Atlantic Crossing 122
Roland Piquepaille writes "The Times of London reports that seven robotic craft will compete in a race across the Atlantic Ocean in October 2008. One of them, 'Pinta the robot sailing boat,' has been designed at Aberystwyth University in Wales. Pinta is expected to sail for three months at a maximum speed of four knots (about 7.4 kph). Its designers hope the Pinta will become the first robot to cross an ocean using only wind power. This 150-kilogram sailing robot costs only $4,900. The transatlantic race will start between September 29 and October 5, 2008 from Portugal. The winner will be the first boat to reach a finishing line between the northern tip of St. Lucia and the southern tip of Martinique in the Caribbean. Here are additional details and links."
Re:how about something a bit simpler (Score:5, Informative)
I'm no expert on robotics, but surely building a house is surely far harder than crossing the Atlantic for a robot?
And yes, it is a little bit harder than crossing the Atlantic. But much more interesting (to me, anyway).
Re:It's a bit small! (Score:4, Informative)
Call me pedantic if you like, but... (Score:3, Informative)
Re:how about something a bit simpler (Score:4, Informative)
You've also got to account for obstacles (admittedly not many) and currents (which could be very significant for such a small boat).
Re:It's a bit small! (Score:5, Informative)
Actually, building self-righting / uncapsizable boats is pretty straightforward. Remember that the keel needs to be heavy enough to offset the tipping moment of the sails; normally this means they're really, really heavy. Also remember that the keel is submerged in water, which means that its effective weight is rather lower than it would be in air.
With a bit of forethought, you end up with a boat which will tip over until the keel starts coming out of the water, and then it'll just stop --- any additional heel will cause more keel to emerge, which will cause the effective weight of the keel to increase hugely, which will prevent any further heeling.
Even if by some miracle you do end up with the boat upside down, it's unstable in that attitude and will right itself. Yes, the sails will cause huge water resistance, but that resistance is proportional to the speed of motion through the water; it won't stop the self-righting, it'll just cause it to happen slowly. (Also, the sails will act to prevent the capsize in the first place, for exactly the same reason.)
What tends to happen these days on decently designed boats is knock-down; a gust of wind causes the boat to be knocked onto its side, up to the point where the keel's righting moment offsets the tipping moment of the wind against the sail. This can be very hazardous to the crew, but hey, no crew! When the gust passes, the boat will right itself (usually even if it's filled with water).
The biggest risk is that all this process is extremely violent; the boat's being slammed about hugely. You run a very real risk of bits of the boat actually breaking. The tension at the base of the mast is huge at the best of times, and if the mast breaks under strain and doesn't come completely free of the boat it can very easily smash through the bottom of the hull. Which Would Be Bad. That's one of the reasons why people like unstayed masts these days; if you get dismasted, you don't end up with a huge, heavy, sodden and very dangerous lump of stuff smashing about on top of your boat --- you're much more likely to lose it completely overboard. Much safer.
While this does tend to apply to yachts rather than dinghies, which as you say largely use humans for ballast, you really do get yachts that size --- the difference is largely design rather than size. My father designed, built and sailed a highly successful yacht only a little bigger --- 15 feet, I believe. It was a bilge keel gaff rig with two monster lumps of concrete for the keel, and slept three. It would heel comfortably to about 45 degrees and then just stop. My father tried quite hard on several occasions to get the cabin windows in the water (much to my horror) and failed every time...
The size of the boat may be a hinderance... (Score:2, Informative)
As for these boats being robotic, I think it is a great test of ingenuity, combining modern technology with the oldest and most time tested form of long distance travel. I would only worry about one of these things being run down by a freighter or similarly large vessel, as a human presence on board is the best way to avoid collisions at sea...
Re:how about something a bit simpler (Score:3, Informative)
Sounds like you've watched the SciFi channel too much. Robot builders does not mean lack of supervision. Nor does use of robots mean lack of general inspections. Frankly, human construction workers typically do piss-poor jobs in the first place until you are talking about high-end customer builders. For track homes, quality often barely able to pass inspection, and that assumes it is actually inspected. Chances are far higher even a poor robotic worker will increase quality a factor of ten or more.
Don't forget, your typical track builder is using illegal workers, workers that are drunk, workers that are high, workers that are more involved in dealing out the back of their truck, if they show up at all, or workers that dropped out of school in the fifth grade. Often, the hardest part of getting a house built, is simply getting workers to show up on time, sober, and ready to work.
Re:how about something a bit simpler (Score:3, Informative)
The kites operate at anything up to 50 degrees to the wind, and are controlled by computer.
Re:how about something a bit simpler (Score:4, Informative)
I maintain my original argument that you can't sail across the atlantic in a straight line, which was all that I was stating in my original post.
If you want to get really advanced, choosing the "optimal" course to sail along might actually be a fairly interesting problem to solve computationally, if you want to take meteorological data and forecasts into account, and update them along the way to choose the best course, while also avoiding lulls, obstacles and storms.