Goal

Build a wing sail for an autonomous one meter sailboat called the Sailbot. The boat will compete in a national competition in the spring of 2018 in Worcester, Massachusetts. The competition is an mostly an endurance race. The previous design was far too heavy, this years wingsail was completely redesigned in order make the weight less than half that of last years design.

Process

I am working on a team with five other members to redesign the sail using lighter materials such as composites, balsa wood and 3d printed plastics in order to lighten the design. To create the foam parts for the trim tab (rear foil in photo) I used a laser cutter to create a profile for a hotwire to follow to cut the foam along the profile. These two inch foam airfoil profiles were stacked in order to create the rear wing, with glue and carbon fiber connecting the pieces. The trimtab controls the angle of attack of the wing, so a servo in the main foil controls the trim of the trimtab. This servo is connected via a carbon fiber rod which fits into a female 3d printed t fitting on the trimtab. Last years team used metal which was incredible heavy, and particularly detrimental because of its height above the water.

As of this writing the trimtab foam profiles are cut and assembled, In the coming week we will covering the foam heatshrink and then beginning work on the mainsail which is over 6 feet tall.

Result

The project will be complete in Spring 2018, so the result will be determined at that time.