Hello and my newbie theory!

[JoshingTalk]

Hello everyone!

My name is Josh, I'm 21 years old and from Surrey in the UK. How you doing?

Thanks for welcoming me to this forum....I really appreciate it as it's good to have a place where you can interact with people.
Down to business however, I am thinking of building an underwater rov (kinda) for my next project....

Like any newbie, I have come in hand with numerous questions that seem too obvious to answer and will make you wonder what has happened to the education system of today....
....the rules for my project are that it must not cost more than £200 for the making of the rov and that it can achieve decent imagery both moving or static underwater at a decent depth.

From what I've seen, actual underwater rov's have not been designed cheaply enough to dive hundreds and hundreds of feet down and capture it on film....I was thinking more of designing a submersible rov....by doing this we would not need the cost of electronics amongst other things and could achieve a deeper depth.
A little idea that sprung to my head was if we were to have a weight at the bottom of a tether rope, then followed by the submersible sphere with as much as a few lights, a battery and a couple of cameras, then followed with another weight above that to balance it out.
(Bear in mind I feel ridiculous clueless right now....)
Then we could lower the aforementioned design into the Sea (yes, sea) and once it has reached the required depth, we could move the boat we're lowering from, slowly in order to pull along the camera (around an object such as a shipwreck). We would of course have a tether line to monitor the camera's imagery on board.

I look at what I've just written and wonder how viable this really is....what I need to know from you guys is, whether this is do-able or not? And if not, which part of logic did I skip?
I'd appreciate constructive criticism as I know that it's easy to laugh behind the computer screen....I'm sure you guys are not like that anyway.
My aim is to capture imagery of a shipwreck using a submersible rov built for under £200.

Many thanks and looking forward to your replies!

Josh.

[simpleben77]

google "rov in a box" sounds like just what you need!

[JoshingTalk]

google "rov in a box" sounds like just what you need!

I had seen that although it does not quite fit my description of wanting to build the project myself to a unique design and use it as more a submersible rather than relying on the electronics.
I will look further into however and thanks for your help.

[thegadgetguy]

So you are basically describing a waterproof camera with lights on the end of a tether? Do I have this right? I don't think there is any reason it wouldn't work, from a technical standpoint. I think your main problem would be not being able to move around. I don't know what kind of water you would be operating in, but my experience is that even small waves/wind can move a boat quite easily. Add to that that your tether might be 300' long, and it probably wouldn't be very easy to navigate. Overall, an interesting idea worth looking into.

Welcome to the forum and good luck.

[JoshingTalk]

So you are basically describing a waterproof camera with lights on the end of a tether? Do I have this right? I don't think there is any reason it wouldn't work, from a technical standpoint. I think your main problem would be not being able to move around. I don't know what kind of water you would be operating in, but my experience is that even small waves/wind can move a boat quite easily. Add to that that your tether might be 300' long, and it probably wouldn't be very easy to navigate. Overall, an interesting idea worth looking into.

Welcome to the forum and good luck.

Yes! Sorry for the poor explanation....when I get round to it, I'll try and draw a picture for all to see!
I understand your viewpoint and thank you so much for taking the time to write back.
I would like to operate in the Sea, looking into a shipwreck so depending on the weather, hopefully calm waves. I will continue to think about strengthening the tether or making the camera more accurately positioned.
I hope other knowledgable people from this forum will be able to share their ideas with me! So far, so good!
As I say, I'll keep you updated and thanks again.

[thegadgetguy]

So what depths were you hoping to hit? 300' ? 600' ? Deeper?

Also, from what you have stated, you don't want any electronics of any kind, other than cameras and lights. Correct?

[JoshingTalk]

So what depths were you hoping to hit? 300' ? 600' ? Deeper?

Also, from what you have stated, you don't want any electronics of any kind, other than cameras and lights. Correct?

As deep as can go I guess? I realise that another big problem will be the pressure and so what is a cheap but cheerful material to use to combat that....I've done some research on syntactic foam but that seems a little expensive.

Yes, to be a bit clearer, I don't think I'll need other electronics....
I won't need the rov to move, dive, flip or anything so that takes away the use of all electronics based on that. I would run the camera and lights off a battery, meaning no need for another voltage tether to hit the water.

Once again, sorry for the vague answers. I am doing my research as I continue to talk within this forum so hopefully I'll be a bit more knowledgable soon. I felt t was best to see how viable my plan really is before launching myself into months of hard work.

Thanks.

[Unorthodox]

So in effect, a camera on a string?

In that case, your concern is certainly going to be current and boat forces acting on the camera. You need to take into account that a negatively buoyant ROV is going to get jerked around by the surface forces acting on the boat where a neutral or positive ROV would have some damper because of slack in the tether.

Also having no control on the ROV itself means you have no real control over what your looking at either, so unless you know there is a ton of really cool underwater scenery where you are, and dont care what you get to see Id be afraid you will be very disappointed.

Now if you were thinking of a sort of towed array with cameras and a data line, that would work out alright, but again your camera focus is going to be limited since there will be some inertia at play and time delay to translate a change in boat direction while the slack in the tether is taken up again.

What may help is if you give a good idea of what it is you would like to see under water, and work out a scheme from there...

[JoshingTalk]

So in effect, a camera on a string?

In that case, your concern is certainly going to be current and boat forces acting on the camera. You need to take into account that a negatively buoyant ROV is going to get jerked around by the surface forces acting on the boat where a neutral or positive ROV would have some damper because of slack in the tether.

Also having no control on the ROV itself means you have no real control over what your looking at either, so unless you know there is a ton of really cool underwater scenery where you are, and dont care what you get to see Id be afraid you will be very disappointed.

Now if you were thinking of a sort of towed array with cameras and a data line, that would work out alright, but again your camera focus is going to be limited since there will be some inertia at play and time delay to translate a change in boat direction while the slack in the tether is taken up again.

What may help is if you give a good idea of what it is you would like to see under water, and work out a scheme from there...

Thanks for the reply! That's a really good way of looking at it....describe the results I want and work backwards from there.

Now I'm not looking to get 1080 full HD cinematic quality (as nice as it would be) but I would like an image that is discernible to the eye. You could look at it and say 'Yes, that is a shipwreck.'

So I guess this has thrown my budget way up into the £500 range? Maybe higher?
How much do you think it would be from your description above?

The aim of my projects is to achieve results using products available on the consumer market and available for absolutely anyone to make.

I was thinking of having a tether so that we can see the image on a screen onboard the boat as this would give us a more accurate view of things down under. I'll draw a little diagram tomorrow and post it up to make it a bit clearer....

....then you can pick out other problems with my design that we can try and overcome!

It's good fun learning about this....thanks for all your help!

Josh.

[thegadgetguy]

You could build a camera rig for a decent price that would give you decent video, the real problem is being able to find the reck. Even when the pro's use camera sleds, it's hit and miss. To have any real control over the sled, you have to be moving, and knowing where the wreck is, where the boat is, and where your sled is, can get tricky. So I think the bottom line is yes, you could build a sled fairly cheaply, but if you want decent video of a shipwreck not on a hit or miss basis, this might not be the best way to go.

Also, I think defining your depth is pretty important when it comes to what you want to make your ROV out of. There's a big difference between 200' and 800' when you are designing an ROV. If you any shipwrecks in mind, you could probably find out how deep they are located and go from there.

Good luck. The begining stages of a project can be the toughest.