First a little introduction before I jump into my design project. I am a 26 year old Lieutenant in the US Navy and my primary job is driving the "big grey things". I currently do not own an OpenROV due to me being on my 3rd deployment, but I plan on buying one as soon as I get back. My degree was in Military History, a bit different from everyone else in this group as I'm no engineer, but I specialize in researching and finding things. My other hobby is large scale RC warships so I do have a knack for building things.
In addition, I own my own 33' fishing boat, which is due for an electronics refit this summer. I also plan to outfit her with an A-frame for survey work. I have already started on my purchase of a towed PPM magnetometer and the side scan sonar is next on my list.
I grew up in Southern CA and underwater exploration has always been on my mind. I remember reading all the Clive Cussler novels when I was a kid and got scuba certified when I was 15. I got advanced certified when I was 17, but time, money and lack of buddies meant my plans were a little curtailed.
Last year after my second deployment, I spent much of my free time researching all the known shipwrecks off Southern CA. It seems as though every wreck within 100 feet (30m) has been found, identified and documented numerous times by local divers, but almost everything after that is a mystery. The UB88 team (www.ub88.org) has done a good job of finding almost every military wreck in the area so I don't really want to step on their toes.
I looked at what GUE Seattle had been doing to locate wrecks in Puget Sound, adopted their technique, and used NOAA bathymetry and 150KHz side scan sonar imagery to identify roughly 50+ unidentified targets down to 300 feet (100m). I established 300 feet as my maximum working depth due to this being my side scan sonar's maximum depth, OpenROV's maximum depth, and about as deep as I can anchor before I need a dynamic positioning system for the boat.
With these targets in mind, my next step is to conduct a survey with the side scan sonar and magnetometer towed behind it to see exactly what the 150KHz SSS data was picking up. If it looks interesting or is just not clear enough, I'll need to send down an ROV to take a look. My end goal is to make a little web-based TV show kinda on the basis of "Treasure Quest" from 2009 on how they went down and identified shipwrecks.
And this is where OpenROV comes in. I REALLY like the design with the computer onboard the ROV instead of having everything topside. It makes it more than just a "floating eyeball". The ability to get telemetry and feedback is the standard that "serious" ROV's are held to and I am glad we are going that route. And considering that the next closest cousin is a VideoRay from anywhere between $10,000 to $40,000, an OpenROV makes way more sense.
In it's current state, OpenROV is rapidly become a great undersea tool as an observation class ROV, but for the purposes I have planned, I need to make some changes.
1. Stability: As of right now, OpenROV is great because it's small and easily deployable. It sits slightly positively buoyant. Great for casual observations, but the ROV moves around widly whenever thrust is applied. This is pretty easy so fix, but it will make the ROV larger and heavier and a little harder to deploy.
2. Larger frame: As mentioned before, the frame will need to be made larger to make it more stable and I will need more attachment points for some of the tooling I plan on installing.
3. Wet-Connectors: I know potting is way cheaper, but it takes out some of the flexibility of the ROV once everything is "hard wired". Wet-connectors will make swapping out motors, lights and accessories much easier.
4. Topside power: I have a feeling everything I want to add is going to eat through batteries pretty quick, so I'm probably going to have to look at powering the ROV from topside. This is going to need a larger tether, etc.
5. Clump weighted tether: To work at the bottom in open water this is a must. Looks pretty easy to implement, but will restrict the maneuverability of the ROV to 100-200 feet around the weight.
6. Improved thrusters: I know this has always been a hot topic and I will be interested to see what the group comes up with.
The design I am looking at altering the OpenROV to is the Outland Technology ROV 1000.
Build a new frame out of heavy duty plastic with floatation on the top and mount the components as shown. Most of what already exists can be readily adapted without having to change much to the E-tube. Does anyone have plans for the Outland 1000 I might take a look at? Or know what thrusters they use? Maybe a materials list?
After the initial frame is done, here is the additional tooling/features I would like to install:
1. Downward facing GoPro with additional lighting. This would be used for creating photomosaics of wreck sites. I'm learning that imagery is far more useful when it is complete and photomosics, while complicated and time consuming are the standard in the field. Can be added without too much work.
2. Two servo based manipulators: With the recent addition of waterproof servos from Traxxas, I would like to take a crack at making a multifunction manipulator arm instead of just a "grabber" with no dexterity. One drawback to using servos is that it won't be able to lift much, but that's ok with me, I'm not ripping up wrecks or anything intrusive. Control is going to be an issue and I am not quite sure how I want to implement it yet. It looks as though a PS2 or Xbox controller will work.
3. Venturi suction dredge: These are relatively easy to make, but directing the suction end requires a manipulator arm. A filtration system will be added at the back to remove any wreck debris.
4. Suction cup attachment to one of the arms: Again not to hard to make, but does require a manipulator arm.
5. Scanning Sonar: Although the Tritech Micron is vastly out of my range ($15,000), new less expensive technology is becoming available as used in the Lowrance Spotlightscan and Humminbird bow mounted AC 360 scanning sonars. Very useful for picking objects out of the seabed if we can somehow integrate this technology.
6. Ultra-Short Baseline positioning system: Tritech already has this technology available, again for a price ($20,000). I like the conversation here and I’ll stay tuned to what comes about.
Thoughts? I know it's a bit complicated, but I feel like I can contribute a more stable frame and get the downward facing GoPro with additional lights working. This would be all I need to make photomosics and conduct pre-disturbance surveys.
I can’t wait to get home and start work on my own and start contributing!