Hi

I want to change the diving system in my Robbe U-47 from dynamic to static. I plan to install a 750 ml tank from Engel.
Then I would like to make my ovn electronic to control the diving tank and the automatic leveling.
Can somebody give me the number of some Integrated Curcuits that can be used as sensor for the leveling?

I think that Analog Devices makes a ADXL ??? that can measure tilt according to ground, but are there other IC's also
that can do the job?

Regards
Tom

Tom:
I also have a Robbe U-47 and I am thinking of modifiying it to static or "semistatic" diving (this is, the possibility of changing trim from scale surface to fully flooded with water line over the deck).
I have already tryed the second option and I think is the most economic eficient procedure: cheap, easy and most regarding.
If I decide for full static diving I would also like the 750 cc Engel tank, but the modification to my existing model should be quite large. And what about the cost?, as I think the best power solution should be Li-Po cells and sure they are not cheap.
Regarding electronics, I am not an expert, but have some experience and I may say you that leveling should only be dynamic and what you need is more or less what helicopter guys call a "heading lock" gyro.
This is basically a piezo gyro sensor with an integrator calculator that taking account of g force value, sense as well as time, is able of calculating the drift from the original position, so it may take just precise corrective action.
I have tryied one of this gyros on my series dynamic diving submarine without much success, rather I prefered it in normal gyro mode rather than "heading lock". But it is mainly due I conected it to the rear dive planes servo and when you send some command this type of gyro produces control surface full deflection.

Jesus Cardin

Hi

I have found a an electronic curcuit for measuring tilt. It's from elektor.de 99'. Just what I was looking for, using ADXL 105 from Maxim.

Regarding static diving, I have two days ago been ordering a 750ml tank from Engel. Quiet expensive one, but I couldn't find any on ebay for a low price. I also have a "bajonettversluss" (metal ring) for closing the two parts of the U-47.
Today I went to the shop to buy all raw materials for doing a complete conversion of the inside. I will post pictures later when I start to rebuild the sub.
As you mention it's a very timeconsuming job, but I want to do it, because I'm not satisfied with dynamic diving.
I use 12 Nimh 3300 mAh (7,2V 6600 mAh) cells and it should be possible to find place to the 750 ml tank and the batteries inside the tube.

Later I will optimize the gyro software, but I think it's first a project for 2007.

Tom

Have you guys seen my site's build thread on my robbe engel conversion with suntech auto leveller and depth control?
It's at http://magpieyachts.com/building7.html
and http://magpieyachts.com/building8.html
Have a looka nd see how I did it. It has 15 nimh sub c 3600s and I now get an hour of running at scale speed with 3 or 4 static dives to the bottom and back etc. I'm very happy with it. The whole build took me 3 months and was a blast!
Jason

Yes, I saw your site.
It gives some inspiration but I can't just copy your princip because my setup is different. I have a "bajonett" ring that is a bit smaller than the diameter of the framework, so I have to completely redesign the framework. The front rudder is controlled by a servo inside the tube, in my U47 so it also takes some space.
But I have a clear idear about how I must do it all, and I also have made half of the parts I need for the new framework.
I also have to do a slightly modification to the Engel tank because its more than 75 mm in diameter and my new framework only accept up to 80 mm. Therefore I made a new socket for the motor, so that moved slightly more to the center.

Here is my sub with dynamic setup
http://www.rcgalleri.dk/html/gal_visbil.asp?ID=2070

Nice boat!
Those bayonettes are a good idea. I wonder-is that an engle lafeyette type? It looks similar. They have a very nice WTC layout with a 750m tank. Yours might be smaller though.
Here's a ;ink to a page of pics of one. They have the same pull out WTC as the u-47.
http://www.subpirates.com/viewtopic....r=asc&start=15

Yes, I'm changing layout for something simular to the lafeyette.