RE: [PSUBS-MAILIST] Sub launched ROV

Have as look at the ones James Cameron used on the Bismark and Titanic... Not a whole lot of Tech info on them however a few simple ideas get around some of the big problems...

His brother has made the ROV square with nothing protruding, that way there is little chance of getting snagged..

The tether is a tiny fiber optic cable that is spooled out from the ROV... No need for a cutter as if you got caught up the surfacing 'Mother Sub' would break the line...

I think you could do the same with a small coax cable, these cables are allot less expensive and there are already connectors available that rotate. (Not ever that hard to manufacture)... down a single core coax you could get real ingenious controlling the ROV with a computer OR go simple and have the ROV running off its own Battery power, Controlls via a RC Plane/Car remote controll and have Video returning down the same cable. We do this currently in some Broadcast applications. It would help if you can adjust the gain of the controller output and also make sure your Video and controller signal frequencys are as far apart as possible.

I have been running this round in my head a bit and it seems to be simple if I was to go down this path.. I would have the spool attached to my Sub, this way if there was a breakdown i could winch it back in... It would also be great to (Like Jake and Elwood) have a sister ROV to rescue the other...

Anyway have a look at the pictures and see what you think...!

http://www.popsci.com/scitech/article/2003-04/big-movie-uses-tiny-subs-probe-titanic

http://images.google.com.au/imgres?imgurl=http://www.ultimatedisney.com/images/ghosts10.jpg&imgrefurl=http://www.ultimatedisney.com/ghosts.html&h=160&w=213&sz=10&hl=en&start=8&tbnid=CYYSkU_uRUYQvM:&tbnh=80&tbnw=106&prev=/images%3Fq%3Djake%2Belwood%2Brov%26gbv%3D2%26hl%3Den

-----Original Message-----
From: owner-personal_submersibles@psubs.org [mailto:owner-personal_submersibles@psubs.org] On Behalf Of ShellyDalg@aol.com
Sent: Saturday, 21 June 2008 5:19
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] Sub launched ROV

Hi Ian. A reel would need the connection to swivel, and would attach to the sub in a simple multi-prong electrical through-hull. A possible option would be a cone shaped cable holder, where the cable spools off, but it would still need to curl up the cable. Retrieval could be accomplished by rotating the cone shaped spool. ( simple motor drive )

If the sub was say 200 feet deep, and the cable was 100 feet long, you could cover an area about 100 feet around the sub, or go deeper with the ROV ( but with less area )

It seems like a fiber-optic cable would be prone to problems. Wouldn't it work to use coax cable for the video feed?

As for power, I would rather see a battery on the ROV so no heavy power cables are needed from the sub to the ROV. Just low voltage wires so they could be cut if needed.

The pressure proof container is the easy part. Just a stout piece of pipe with a window in the front, camera and battery inside, control panel for motor drive and dive plane positioning. Make it neutrally buoyant with a drop weight. It would be small enough so you could make the whole thing from stainless at a reasonable cost. Something about 24 inches long and 12 inch dia. for the pressure container would be enough if you packed the stuff inside right. Some fixed ballast tanks to achieve neutral buoyancy, and with a grabber arm on the sub, you could make a simple docking mechanism so the ROV could be stowed away in it's holder after retrieval.

Low voltage solenoids inside the ROV for powering switches so no heavy cables are needed from the sub.

Seems like an eight pair cable would be enough for the minimum, plus the coax video feed.

One problem is voltage drop over a long cable, but with the right solenoids, that would be solved. I had some info on an off-the-shelf video device that was posted earlier this month here on the psub mail thing. It was pricey but was a complete system including cable, camera, and monitor. I think it was built to be deployed from the surface like from a boat or maybe ice fishing.

The cost of a simple camera( about $150), a small TV monitor ( like the small TV/VCR combo made for a motorhome, 12 volt, $99 at Best Buy ) and your own pressure cylinder as a start. Then add the motors and controls, the cable and connections, spooling reel, and various mechanical things like dive planes and drop weight. Doesn't Steve Pierce have something like that he's been working on? I think you can buy an off-the-shelf tiny ROV for about $2500. There's a guy here in Santa Cruz that has one he rents out to boat owners. I remember seeing an advert on it a while back. Anyway, lots to think about. Frank D.

Gas prices getting you down? Search AOL Autos for fuel-efficient used cars.

##########################################################

Important Notice:

This message and its attachments are confidential and may contain information which is protected by copyright. It is intended solely for the named addressee. If you are not the authorised recipient (or responsible for delivery of the message to the authorised recipient), you must not use, disclose, print, copy or deliver this message or its attachments to anyone. If you receive this email in error, please contact the sender immediately and permanently delete this message and its attachments from your system.
Any content of this message and its attachments that does not relate to the official business of Seven Network Limited or its subsidiaries must be taken not to have been
sent or endorsed by any of them. No representation is made that this email or its attachments are without defect or that the contents express views other than those of the sender.

##########################################################