Homebuilt ROVs Forum

I'm new to ROV's. The frames/propulsion systems are coming along nicely and should be done in a week or two. I am now turning my planning towards the camera, lighting and control. The ROV's are being built by students and will be used in a swimming pool for contest like retrieving an object off the bottom of the pool in the fastest time, manueverability contest etc.. We have several ponds and lakes in the area we would like to explore. Most of the lake and pond water is very green with algae.

I have read several post about LED lights basically washing out under water even though they look extremely bright and project well above the surface. This brings up a few questions what other light source can be used ie.. halogen. I use a 50 watt low voltage halogen in my Koi pond which works fine. Heat does not seem to be an issue so this is one option I may consider. Anyone have a real world experience you want to share about LED's or other light sources pros and cons?


thanks in advance

In my opinion LED is the way to go. Low power consumption and they come in a variety of light spectrums to suit any need. Here is a short list of just a few Professional ROV's using LED technology.

Deep Trekker http://www.deeptrekker.com/

Video Ray http://www.videoray.com/homepage/profes ... hting.html

SeaBotix Inc http://www.seabotix.com/products/lbv200-4.htm

Seaeye http://www.seaeye.com/falcon.html

Thanks. Next question what wattage should I use for a small ROV. 20"x18"x9". I have found LED beads in 3, 5, 10, and 20 watt ratings. I know the real answer is "it depends". Assuming I will use the ROV at depths of 0-35ft in a lake would 5 watts work or is the rule of thumb the more watts the better. From what I have found LED's in the 6000-7000K ranger work best.

These are the ones I purchased. The operating voltage is 30 to 34 VDC.
http://www.ebay.com/itm/-/230820877786? ... &ViewItem=

I had to buy a DC to DC step up transformer to drive them off my 11.1 Lipo on board batteries.
http://www.ebay.com/itm/150W-DC-DC-10-3 ... 416b154e17

Thanks BikerBones (I'm sure there's a story behind the name). That get's me going in the right direction. I work for a non-profit so while trial and error is OK I do not want to waste their money so I appreciate the advice.

amarillo_rocket wrote:Thanks BikerBones (I'm sure there's a story behind the name). That get's me going in the right direction. I work for a non-profit so while trial and error is OK I do not want to waste their money so I appreciate the advice.

LOL I have always been a thin person and the nickname Bones due to being a skinny kid stuck (skin and bones) When I was a late teen I bought an old Harley Davidson motorcycle that I completely rebuilt from the ground up. The locals then called me BikerBones and it has been my screen handle ever since. The bike is now 40 plus years old and I still have it.

Hi Amarillo_rocket,

I'm also quite new in ROVs, yet I had some recent experience with LED lights.
In my first ROV I had two small 12V LED lights (not even sure about their Watts) which I tried in night dives.
I was impressed of how nice my camera showed (see snaphshots).
In my new ROV I have made 3 new 12V LED lights but three times bigger than the old ones sealed by embedding them in transparent resin. I have not tested them yet. The new lights are cheap (approx. 8 Euros or 12$) and the resin also costs about another 12$.

Yet, my cameras have a very high light sensitivity (less than 0.5Lux) as I want to get videos even during night or at depths higher than 30m.
On the other hand, no matter how much light (or what type of lights) you are planning to use, you will have problems with the algae or and/or floating particles. I have only tested my ROV in clear waters, but from scuba diving experience, I can tell that if the water in the ponds has a lot of algae then adding light probably will make things worse due to refraction. Anyway, you have to try to see the light and visibility conditions close to the bottom.

Moving the lights away from the camera can help with reflection off of particles in the water - the light is reflected back at the lights, not the camera.

While were on a roll talking about lighting I have a question as well. Is there a best location for the lights in regaurds to the camera? Like either above or below it? Ive see them placed both ways but have to wonder if when you are in turbid waters the light being below the camera could cause issues...???