SUBMARINE

[DANISH KHAN]

HI, I AM WORKING ON COLLEGE PROJECT IN WHICH I HAVE TO MAKE A SUBMARINE.....PLZ CAN U TELL ME HOW CAN I MAKE THE SUBMARINNE SINKING AND RISING MECHANISM FEASIBLE AT A LOW SCALE AND HOW CAN I MAKE THE MOTORS WATERPROOF...THE MECHANISM SHUD BE SUCH THAT I CAN KEEP THE SUBMAINE AT DIFFERNT LEVELS IN WATER....PLZ DO REPLY...

[HighFrequency]

First, please don't type in CAPS. Second, it sounds like you want people to tell you how to do the hardest part of your project. Here are my suggestions:

1) Make an attempt at a design. Try to work out the problems for yourself. Do some research. Lots of submarines have been built, there must be some literature somewhere.

2) If you run into a specific problem (not "Please make my project work"), and it is electronics related, come back here and ask a specific question. You may get an answer, are a clue to point you in the right direction. If it's not electronics related (like how to waterproof an engine) try another forum. An automotive forum might have some engine waterproofing detail for example.

That's my two cents.[/list]

[bodgy]

Perhaps one way to make a model sink or rise is to check out those toys for children - the diver that you bung in a bottle, squeeze the bottle and the diver sinks, release and up he comes. I'm sure they're still around.

This would be easier than trying to emulate the way a real submarine works.

After that, you can think of what causes the little diver man to work, from that maybe a sensor that could be used comes to mind which would allow some degree of control of the sinking/rising process.

As far as waterproofing motors, what are the motors going to do, where are you thinking of putting them, what parts of the motor are going to come into contact with the water if at all?

Using the idea above for buoyancy - your motors might not need to get wet.

List here your thoughts on how to achieve buoyancy or the lack thereof, and then advice can be offered.

For what it is worth, and this may be of no help with your college, I always pay more attention to someones thought process and ideas than whether a project works perfectly first time. Of course having a project that works totally is wonderful, but minor failure is great for making better ones next time.

Is this project a solo one or a group effort?

Colin

[bdickens]

My son and I built one a while ago and have another in construction.

Look for the submarine links. This one http://www.hrfsbo.com/sub/ is pretty good. I don't like the ballast tank system but if you must... you must.
(I prefer to just use bilge pump motors to push it up/down, at 70 ft, I never got airpressure to work)

Bilge pump motors are "generally" waterproof, but at any rate, easily replaceable. We used PVC for a couple of oil filled motors but it was more work than it was worth. Used RC car speed controls (with reverse).

We use ethernet as a tether. Hacked linksys router with webcam and some sensors hung off. The new one will have a web server so we can get better controls.

I never did get the sonar to work well underwater so we are trying that on the next round.

Hope that helps. As a couple of other posts indicated, try something, see what does not work. My first run was WAY overengineered.

[Chris Smith]

Thirty years ago I copied the real subs ideas of sinking and raising.

At the time I had canned pressure in the form of a Freon so that part was cheap and easy.

You need to find a tiny air tank with valves to do this these days.

You partition off segment tanks in the sub with bladders or tanks to receive water and use air pressure canned to blow it back out.

Weight in weight out, up and down.

The exiting of the air is done with a servo valve to dump the existing air out of the tank letting in heavy water to sink the sub, and then close it to sink and then chose to rise.

The other servo is attached to a pressurize can of air in the sub to reverse the water flow back out to raise the sub.

You have to do your math for a perfect balance and the tanks of air/ water should only cause the sub to be come a little less than ZERO buoyant, [ounces or pounds depending on size] while the drive motor and flaps can drive the sub up and down.

A slight negative buoyancy is permissible but in order not to lose the sub in a catastrophic failure, you must have a timer set in the event of any failure to blow all of the ballast should all communications and systems fail over time.

You can set the fail safe to trigger for X amount of hours after all communications or motions are lost, or any other failure that will eventually trigger and blow all of the tanks and make the sub recoverable.

You can even use a back up pressurized tank for this specific purpose.