ROV

Moonwalker · June 01, 2010, 21:35:16 CET

These plans are ok for 50-80m depth. But for 300m it would not work with bilge pumps! Cat5 will make too much drag for such depths and I dont think it will work.
But still building one for 80m depth would give some nice videos I guess and it would not cost too much.

caldaland · June 02, 2010, 17:11:19 CET

you can email this guy with any problems.
http://home.comcast.net/~homebuiltrovs/seafoxretrofit.html

caldaland · June 05, 2010, 02:45:29 CET

moonwalker did you see this post?

Moonwalker · June 06, 2010, 02:06:15 CET

Yes ofcourse but these homebuilt ROVs on the net are all for max 100m depth.
I'm doing my homework and checking out if what I have in mind is doable and within budget.

shanook · June 06, 2010, 09:49:21 CET

does the rov have to move about I mean what is ur idea for doing it. If it is just checking the bottom can you just hang a camera with a weight and letting it down of course u add LED lights. All it would cost is a camera. I mean it wont look professional but if it serves its purpose .........

Moonwalker · June 07, 2010, 12:14:01 CET

I'm planning it to be manuverable. At 300m the cable would make too much drag to move it by the boat.
Anyway will let you know of the progress when I start

shanook · June 07, 2010, 12:44:22 CET

yep it would be interesting to see what comes out.........if u need help just shout ...........

busumark · June 17, 2010, 14:07:35 CET

www.elettronicaenne.it

these have ROV that go up to 400 mtrs but there is not price

Moonwalker · June 18, 2010, 00:52:10 CET

Thanks Mark but when the price is not listed it means only one thing

I'm still gathering information but from what I have so far it will not come cheap.

EmicMalta · June 18, 2010, 06:58:36 CET

what kind of cable is it going to be used? Does that prussure makes problems in the insulation? If you need any kind of CCTV advice let me know

Moonwalker · June 18, 2010, 10:31:01 CET

From the research I have done I think I have to go with fibre optic. I'm still waiting for the pressure answer from the manufacturer.
Cat5 cable might work too but I am planning something thinner with lowest drag possible. If anyone here has some experience with fibreoptic pls pm me.

guido99 · June 20, 2010, 07:00:22 CET

First you need to determine what purpose the fibre optic cable is going to serve.
a) transmit video only
b) remote control cababilities for the rov + video

For video only a combination of video to fiber transmitter/ receiver the size of a slim packet of cigarettes will work just fine, these are powered by a low voltage dc supply.

For option b) you would most likely be better off going with a network media converter (ethernet Rj45 to fiber) this will enable you to steam video through the network + control the rov provided you know or are ready to learn the basics of LPT(printer port) communicaions/interface. Also bear in mind that with this setup you will need a Laptop above and inside the rov

The fibre optic cable:

Yes fibre is very thin but for it to be practical and durable it must be protected so expect realistic diameters for your application to be about a minimum of 2 to 3mm diameter, also this is not for underwater cables but indoor/oudoor cables used commonly for fibre to the home apllications. Dont worry this type of cable will work fine underwater.

Multimode fiber (mm) or Single mode (sm) fiber ?
mm ok for short distance <3km (cheaper hardware), sm ok for long haul applications (more expensive hardware)

How may i be able to help you ?
Source cable and hardware, splice/terminate cables and setup hardware.

Moonwalker · June 20, 2010, 12:14:54 CET

Thanks guido for the usefull info.
The FO will serve for video and control too. Communications will be network/IP based for both video and control. I already located some Ethernet to FO converters but if you know of some tested model its better. Laptop above is not a problem but inside the ROV I will use a microprocessor - I have some basic and advanced electronics knowledge

. Only free time I dont have much

About cable thickness 3mm will be just fine although 2mm is better. I was going for sm cable since it is thinner than mm.
I need more info about why sm cable is more expensive. Is it the cable, the terminations or the converters?

guido99 · June 20, 2010, 14:19:22 CET

sm cable will be more expensive due to the more precise electronics i.e. sm uses laser as a light source while mm uses led.
Don't go for sm because of smaller diameter. Sm just has a smaller diameter core, this does not affect the o.d. of the finished product.

Cant say i tested this model but the price is right

http://www.amazon.com/TRENDnet-100Base-TX-100Base-FX-Converter-TFC-110MSC/dp/B00007IFE8/ref=pd_cp_e_1

Moonwalker · June 21, 2010, 10:59:12 CET

Thanks again. That price is perfect!
Now any links for the cable pls? It must be thin and flexible and not easily breakable since it must be unrolled and rolled back every time.