I am constructing an autonomous, unmanned boat for voyages of several months. The boat will be a trimaran, approx. 5m in length amd have a wing for a sail. Traditional autopilots use a linear actuator to move the tiller but require several adjustments per minute. They will consume a lot of electricity and probably wear out mid-voyage. We are looking at wind-vane designs to steer the boat. Wind-vanes are able to steer for great distances without adjustment. Can anyone recommend a design for a wind-vane? All of the designs I have seen are, rightly, for yachts. The idea is to set/adjust/monitor the vane using electrics when necessary, but after that, rely on the wind.
The aries windvane is probably your best bet. You would need to fabricate quite a bit of equipment to adjust the heading and fix it. You would also need some custom software to navigate and take wind direction into account. Oversizing the autopilot tiller actuator and accounting for the extra power consumption with solar panels and/or turbines seems like a more fruitful method. What are you planning on doing to provide motive force?