Last December one of the largest earthquakes in recorded history (measuring 9 on the Richter Scale), struck just off Sumatra, Indonesia, in a fault line running deep under the water. The rupture caused massive tsunamis, that hurtled away from the epicenter, reaching shores as far away as Africa.
A few days after the disaster, a friend and fellow fishkeeper sent me an e-mail containing a number of images depicting strange, deep-water fish that were supposedly washed up by onto shore by the huge waves and cataloged by scientists.
Although these are, in fact, genuine images of some very strange deep-sea creatures, these photographs have nothing to do with the Indian Ocean tsunami. They date from mid-2003 and were taken by researchers on the NORFANZ voyage, a joint Australian-New Zealand research expedition conducted in May-June 2003 to explore deep sea habitats and biodiversity in the Tasman Sea. These photographs can be viewed on Australia’s National Oceans Office web site.
While I hate to see these creatures dragged up from the abyss, I am very much a “deep junky”, and take great delight in learning more about marine life from the murky depths. Mostly, it is for this reason that I have developed such a strong interest in both powered and unpowered DIY ROV technology.
Ever since I discovered the article about the $99 home made ROV, I’ve been all excited about building my own and using it to attach decent lines onto wrecks that are below 300 feet. In other words, wrecks that are deep enough to dive on technical scuba, but too deep to spend bottom time searching for. Since the $99 ROV does not have thrusters, I set out about finding a way to build some when I discovered Doug Jackson’s article about his adventures building this ROV named BOB. I have say, I really like his design! Not only does it use reasonably priced parts, but he’s been very clever in how he has used modified vintage Atari video game controllers and relays to drive the thing.
Here is a quick overview of what he has used:
Five, 500 gpm Johnson Bilge Pumps as thrusters. He got them for $10 each, but they now cost about $20 when you buy them from Boater’s World.
Atari vintage joysticks from eBay
PVC pipe, epoxy, wire ties, and Cat 5 cable from the local hardware store.
A 9V battery to power the relays
A 12V battery to power the pumps
An Atlantisâ„¢ Guide View Underwater Camera System
A television to serve as the monitor
Doug provides very detailed directions on how by constructed BOB, and even talks about how a person might modify the pumps to be fitted with propellers, thereby making the ROV more effective in areas of heavier current.
In BOB’s lake trial, it was tested to 60 feet and performed well. A neutrally buoyant tether cable was obtained by attaching 1 foot sections of foam pipe insulation every 6 to eight feet. Telling how close the ROV was to objects was apparently difficult, and Doug mentions that it either needs better lighting or lasers that cross 6 feet in front of the device might be of help.
Here are some direct links to areas of interest on Doug’s site:
Again, I really like Doug’s design. I think the most challenging improvements would be to increase the thrust by using propellers and to prevent the pumps from flooding under greater pressure. I’m also not sure about how one could manage the voltage drop over a longer tether cable. I don’t believe the design, as it is, can make it 400 feet down to the S.S. Tahoe, but I do see it making the dive with some HID light, tighter seals, and a little more thrust.
It’s not remotely operated, so you can’t really call it an ROV, but the guys over at engadget.com and divester have posted stories about this nifty little 99$ creation last week, and I think it’s pretty cool. Apparently it was made for under $100 in just two weeks. It has two cameras, an IR illuminator, some cleverly bent PVC pipe, one heck-of-a-lot of zip ties, a glow stick, and a 100 foot tether by which it receives power, and sends a video feed to the surface. I especially like the clamps that hold the camera housing together.
They didn’t mention the depth rating, but assuming that the tether could be extended, and the housing could take the pressure in deeper waters, this might really be a great technical diving tool for finding wrecks, and attaching decent lines to them. Of course the lack of thrusters would be problematic for working in waters with current, but I can think of one primed-to-dive wreck in Lake Tahoe that sits in 400 feet of water with no line on it that this baby might just be able to lend a hand with. Can you say S.S. Tahoe?
I’m actually thinking about making one of these for myself. If I do, here is a list of things that I would add to it: