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Freedom isn't free
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When do they install the asym chute launcher?
 

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Once known as Hartley18
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5,179 Posts
Want to share with you the video of my sailing drone that races regattas autonomously. Winner of the World Robotic Sailing Championship 2014 in the MS class.

https://www.youtube.com/watch?v=8YONrJKWIiE

Below photos on race path and boat
Now, THAT is really clever! ..and a great video also. Thank you for sharing it with us.

Congratulations and very well done!! :)
 

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Discussion Starter · #9 ·
Thanks Classic 30

Hi Rob,

What I found is that going downwind it is better to steer to compass rather than the vane.
This is because the boat is rolling and apparent wind is light so the wind vane is making large swings can you can't fully compensate with filtering. Also going downwind, the sails don’t need to be as precisely tuned as upwind.
So yes, it can jib accidentally in wind shift but in fact it is relatively stable.

Upwind, the boat steers itself to the wind and is very reactive to any wind shift. It tacks when it reaches the lay line or if it spends more than a certain amount of time on one tack or if it is too far from the direct course. This is to avoid having only one long tack or obstacles.

Thanks for watching the video.

Chris.
 

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Once known as Hartley18
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5,179 Posts
What I found is that going downwind it is better to steer to compass rather than the vane.
This is because the boat is rolling and apparent wind is light so the wind vane is making large swings can you can't fully compensate with filtering. Also going downwind, the sails don’t need to be as precisely tuned as upwind.
Chris, I have one question: how well does it handle larger or turbulent waves? I would imagine that the movement of the top of the mast would make reading wind direction accurately very difficult.

If it's a problem, there are mast-head wind sensors on the market that incorporate an internal GPS to negate the effect of mast movement on wind direction sensing. They're not cheap or small, but perhaps you could make something up for your next boat... :)
 

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Discussion Starter · #11 ·
Hi Classic30,

This is a problem and it took me some time to fix it. I solve it in different ways :
- through high pass filtering. I filter a lot the wind direction which by nature is relatively stable. Much less the wind angle and bearing which are very dynamic. The calibration of parameters is important.
- upwind the boat is steered to wind angle to keep the target apparent angle, about 32 degrees.
- the wind vane has little inertia so it really reflects well the wind angle. In fact the boat react very quickly and so it is constantly optimizing the angle when going upwind.
- In fact she reacts a bit the same as on a large boat when there is a significant swell. It is very surprising to see.
- when wind is light, the boat filters more the wind angle and the target wind angle increases.
- finally swell and boat movement is messes compass reading, so a lot of calibration is necessary and as for a real boat, a lot of testing !

Best,

Chris.
 

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Bristol 45.5 - AiniA
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Scale this up, add a solar panel, video camera, and satellite phone and send it off to circumnavigate. You could sit at home in the comfort of your basement, none of that annoying seasickness or possibility of dying, and enjoy 'your' circumnavigation.
 

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Discussion Starter · #14 ·
Hi Kilarney,

I also enjoy sailing my boat ....
This was just a summer project that I wanted to do for a long time. It was interesting to spend time to make her run properly, needed quite a lot of time on the water but the result is satisfying.
 

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Once known as Hartley18
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Scale this up, add a solar panel, video camera, and satellite phone and send it off to circumnavigate. You could sit at home in the comfort of your basement, none of that annoying seasickness or possibility of dying, and enjoy 'your' circumnavigation.
...watching your little ship get run over by a supertanker. I suppose at least posting the video might get a few hits on Youtube. :)

Maybe a good idea to add AIS also? That should at least scare the crap out of the supertanker driver.. "[email protected]#k! we're about to hit something! Where is it?? Anybody see it?!?" :D :laugher
 

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Discussion Starter · #16 ·
:):) That would ruin hours of work !!!!

On AIS, it really needs a bigger boat, but my next project is to have two of these racing against each other and exchanging through the Xbee module their positions and bearing so that they can avoid each other and give proper right of way (starboard and marks). Like AIS ... but with racing priorities in addition.
 
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