Servers by jDrones

Autonomous sailing boat wind direction

(Connor) #1

I am currently attempting to convert an RC sailing bot into a fully autonomous sailing boat however there is something that i cannot work out, ive got a pixhawk and arduino that will be used as the brains for the system and have a magnetic shaft encoder that will be used as the wind vane.

my issue is that on mission planner i understand that you are able to set the way points and the boat will follow these, what happens though if the way point means that the boat has to try and sail into the wind. what is the simplest way to avoid this happening? would it be to send mavlink messages to the pixhawk or is there a way to solve this issue in mission planner.

any help would be much appreciated.


(Dave) #2

I saw a post from a Dev recently stating that Ardupilot for Sailboats is in the works but some months? out so I don’t believe there are features currently in Rover to do what you want. There was also some discussion about a suitable wind direction sensor. I have the same desire to build an Autonomous sailboat after having good success with a wheeled Rover.

(David Boulanger) #3

Sailboats won’t work with the code as it is now. Unless you are off the wind and trying to go in a straight line. It will be interesting if ArduSail does materialize and the various parameters involved. Wind direction, Heel angle, Speed, Weather helm and on and on.

(rmackay9) #4

Good to see we have someone else interested in sailboats.

We have an enhancement request here to add support for sailboats and I’m pretty motivated to make it happen. Philip Rowse is also working on a windvane. He showed me a picture the other day of it mounted on a thunder tiger sailboat (I have the same boat).

We will certainly need to modify the navigation code so that it doesn’t attempt to sail too close to the wind.

If you’re looking to implement something yourself until we built it out officially in ArduPilot then I think using Rover’s Guided mode would work. And then the arduino could send in commands to sail to locations so that the vehicle never tries to go upwind.

(James Pattison) #5

There are other ways to deal with sail performance than a windvane.
An airspeed sensor with both ports exposed obliquely (like 2 sides of a triangle, with the vertex at ships head) will not give direction, but will let you know what the airflow is doing as you turn into or away from the wind (and hence allowing some logic to deal with that). Just a thought.

(David Boulanger) #6

Not a bad idea but wind down by the hull with waves and stuff could give very inaccurate information. I was in 15 foot seas once and on top of the waves made my eyes water. When I went down in between the waves it was totally peaceful.