World robotic sailing championship 2010

Take an eclectic fleet of experimental radio-controlled model yachts. Add a mix of engineering and computing students from around the world. Add coffee, shake, and let the engineers work for a year. Then turn the boats loose on the race course- and leave them entirely to their own devices. That is the essence of the World Robotic Sailing Championship.

I caught a bit of the 2010 competition today. The weather was less than ideal; most of these are very small boats (typically 50 cm to 2 m long) and 15 knots of wind can whip up seas that are, to these boats, what a Force 8 is to the typical cruiser. But by the time I got to the Kingston Yacht Club, things had calmed down enough that a few teams were out on the course.

These are highly experimental boats, and just about anything goes. The class rules specify maximum waterline length (2 m for Sailbot, 4 m for WRSC) and beam (3 m), and competitors must be less than 5 m from keel to mast head. Propulsion engines are prohibited, and the entire decision-making and control system must be autonomous (with an emergency radio-control override). Previous competitions have seen fin-keel monos racing alongside cats and tris, with rigs ranging from ordinary sloops to rigid, soft and even articulated wingsails.

While the dimensions in the class rules may appear to favour multis, this isn't necessarily the case. The 3 m beam limit comes from a test where the boat must pilot itself through a narrow (3 m wide) channel defined by buoys- a less beamy boat has more margin for error. And, of course, we must remember that stability scales quartically, while displacement scales cubically and sail area quadratically. It becomes extremely difficult to design and trim sails for a one to two metre cat that will make good use of the wind without flipping the boat- the useful wind speed range for a given set of sails is only a few knots, and a gust can bring a capsize in a fraction of a second. The monos, despite their slower sprint speeds, have tended to fare quite well in this competition. (In 2006, Waterloo brought a couple of light, tremendously over-canvassed cats, one with a wingsail, that could easily outrun anything in the fleet- on the rare occasions when they could stay right-side-up in the gusty conditions.)

I must confess to a bit of home-team bias, having worked with the Queen's mostly autonomous sailboat team in their early years. Here's a look at their current boat. A clever system of lines and blocks allows the sails to be trimmed with just one winch. The team is working on a larger, four-metre boat for oceanographic data collection.

Queen's MAST boat on shore

Queen's MAST sailboat

This Austrian robotic sailboat, a computerized and fully automated Laerling, was out on the lake for its endurance trials today. Apparently, this one uses a fuzzy logic control system to help guide its command decisions, and with 285 W of solar panels keeping its computer and servos powered up, it was quite happy to loop around the endurance course over, and over, and over again.

Austrian robotic sailboat

All in all, it's quite a fascinating competition, and I suspect that some very interesting things will happen in this field in the next few years.




Add new comment