Is "in flight" mag calibration available for boats? GPS heading?

ArduRover ArduBoat
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As in title of post, is “in flight” calibration available for boats? What about §GPS heading? is it available trough 2xF9P RTK GPS?

Thanks.

p.s. @rmackay9 is loiter for omni thruster coming any soon?

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Hi @Corrado_Steri,

Yes, inflight calibration of the compass is available in Rover/Boat. I think it is described here on the wiki and the procedure is you set COMPASS_LEARN to 3 and then drive the vehicle around mostly in circles. I’ve used this successfully on my mapping boat.

GPS-for-yaw as we call it is also available for boats although I haven’t tried it personally yet I’m pretty confident that it works because a number of users here on the Rover-4.1 forum including Kenny and Yuri Rage are using it all the time.

Loiter for omni thrusters and also using lateral thrusters for Auto missions should happen some time after we complete the SCurves for rover project. Of course Loiter works with omni thruster boats but they rotate like a regular boat which of course is unnecessary for these boats.

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I’m confident that a moving base configuration would work on a boat with similar performance as a land-based rover. Setup has become very easy with firmware improvements since I first started using it.

And inflight calibration is actually my preferred method for rover compass setup!

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Thank you guys very much. One more little question for @rmackay9 . How many watts a boat of around 30 kg at 1-2 m/s would pull?

Thanks

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@Corrado_Steri,

I’ll take a random guess that a 30kg boat at 1-2m/s requires about 250watts. 30kg is probably a little smaller than mine which has a 1Kw motor and a top speed of about 3.2m/s. The speed vs power curve is completely non-linear though so even a small increase in speed can require a massive increase in power.

I put a speed vs power graph for my boat on this blog post.

Another random tidbit I learned during my recent project is that a longer boat has a higher top speed because of the effect of the bow wave.

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@rmackay9

Thank you very much. I was thinking of using 2 x T200, hope will be enough.

Do you guys share hull 3D by any chance or maybe it can be bought separately?

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@Corrado_Steri,

I don’t know if the T200 will be enough but they are very popular. I think I saw someone using them with a 6S battery and it seemed to have a lot of power. If that fails we support the Torqeedo motors and hopefully we will also add support for the ePropulsion motors. Those are much larger and more expensive though.

I’m not sure what hull 3D is…

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@rmackay9

I think we will go with the 2xT200 at 4S and see.

I meant the 3D files of the boat itself (the hull).

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Please share your findings!
I’m also thinking in getting 2x T200 with 4s LiPo for a 1.2m deep-V boat and use skid steering.