Technology: Boat sets sail on a wing and a computer

日期:2019-02-28 05:04:06 作者:荣遣紫 阅读:

By RICHARD GOULD TRIMARAN yacht that uses wings instead of conventional cloth sails is due to be launched later this year. Planesail, as the yacht is called, can be handled by one person because its ‘wingsails’ have automatic control. It weighs 7 tonnes and is 14.7 metres long. Planesail is the brainchild of John Walker, an aircraft engineer. His idea for wingsails came 21 years ago when a motorboat nearly collided with his yacht and a swinging rope sent him flying. This inspired him to develop a better system for powering sailing boats. The wingsail, which looks like a modern aircraft wing, has less drag and more thrust than conventional sails. As on aeroplanes, the wings have flaps, air-directing slats, and motorised actuators to move them. The wings are constructed from epoxy resins on an alloy framework, with the lightly stressed areas of the wings covered with laminated polyester fabric. Each wingsail is mounted on the hull by a large ball-bearing, similar to those found on small cranes. The skipper can control the actuators either manually, or by a computer called Micromariner. A network of sensors provides it with information on the direction and speed of the wind and the boat. It uses this information to translate a skipper’s commands into signals to the tail and wing flaps. Micromariner also has a system which warns of any developing faults. The electric motors for the flaps are powered by batteries. Solar panels, wind generators and a pair of alternators connected to the auxiliary diesel engine charge the batteries. The flap actuators can also be moved by hand. Walker is now working on a boat with more efficient solar panels and electrical components, so that the diesel engine can be eliminated. Micromariner can accommodate either semi-automatic or fully automatic control over the wingsails. In the first case, the computer trims the flaps according to the sailing conditions but allows the skipper to steer the boat. Full control is similar to the autopilot used on most aircraft. Walker believes that his is the first such system to be used for sailing yachts. Walker and his wife, Jean, set up their company, Walker Wingsail, in Plymouth in 1983. They hoped to adapt wingsails for larger ships in order to provide cheap, clean auxiliary power. The first one of these was an enormous triple-winged device fitted to the 6500-tonne MV Ashington (Technology, 19 June 1986). Although the device reduced both fuel consumption and emissions of pollutants by 10 per cent, itattracted little interest,