Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Submarines => Topic started by: johnredearth on March 31, 2016, 07:24:39 am

Title: Arduino Ballast Control and Depth Keeping
Post by: johnredearth on March 31, 2016, 07:24:39 am

Hi all
I am 75% the way through the build of the Nautilus SSN571.  I am using arduino to control the ballast system and now also the bow planes. It’s as cheap as chips to do and the off the shelf stuff is of course not adjustable.  I have made some videos about all this and thought you may like to see them.
https://youtu.be/_cJs9mqJWvI
https://youtu.be/6ADMh5wQ4wA
https://youtu.be/DY6wvH6yDkE
Comments welcome!  Be nice with the code.  I am very clunky at it.
I am no expert in any of this but it all works, and it seems that people should take the plunge and start using this incredible technology!

Title: Re: Arduino Ballast Control and Depth Keeping
Post by: g6swj on March 31, 2016, 09:41:44 pm

Hi John,

Having had a look at your YouTube videos I just love the way you work with Perspex and what you have achieved - the Subtech valve is stunning but the sub conning tower construction shown briefly here  https://youtu.be/yndcGuQnbRg is something else and on a completely different level - it's would make a kit in itself!

Will watch with interest for future updates

Jonathan

Title: Re: Arduino Ballast Control and Depth Keeping
Post by: dreadnought72 on April 01, 2016, 12:12:25 am

Great videos - and I'm very impressed with sensitivity of the pressure sensor!

Don't worry about 'clunky' programs: if you understand them, and they work, all is good!


Andy

Title: Re: Arduino Ballast Control and Depth Keeping
Post by: johnredearth on April 01, 2016, 02:44:39 am

Andy


I bought about three of them to get the right one.  It's easy to get sensors to record pressure 'in' but then when the pressure decreases below the ambient they stay at zero.  This one is perfect. It needs a sealed container however as it also uses the pressure in its environment and 'compares' I guess with the input.  With a piston in the hull however pressure is up and down so it would be hopeless unless sealed from it.  It is good enough to get the boat within 3 cm of the desired depth.  Of course, if I turn off automatic depth keep, use the hydros to go deeper, and take a snapshot and then move it into auto it holds that as well.  It's pretty good, but the hydro is a bit jerky in auto.  I don't care that much as long as it does the job.

This outlines the control system... https://youtu.be/pZ_MRMHgFDo


John

Title: Re: Arduino Ballast Control and Depth Keeping
Post by: g6swj on April 01, 2016, 08:36:10 am

Hi John,

When I watched one of your videos I did smile when I saw both the wine and beer bottle on your workbench - I thought you must really be going for it - only later in the video did I realise that the wine bottle was full of water to allow you to test the pressure sensor!

What pressure sensor do you use? You mention the hydro is a bit jerky in auto - Is this caused by the sensor readings jumping around a bit? if so could they be smoothed?

It's really good to see great scratch model building being pushed to new limits in such a creative way. You have inspired me to have a look round my house to see where I could install a lathe etc - each time I look however I find the same answer - not enough room (:

Jonathan

Title: Re: Arduino Ballast Control and Depth Keeping
Post by: johnredearth on April 01, 2016, 09:53:23 am

HI


The sensor is a MPXV7007G, and no I don't mix wine and beer.  Or maybe I do..  Nor sure.  You should try to make space for a lathe.  Knock a wall out!


Cheers