After the successful completion of my Mid-Sized Observation Class OpenROV, it's time to move on to other projects. The AUV project is still a ways as we work on some of the sensors required, namely an altimeter and a better Inertial Navigation System, but it is still on my to-do list and I'll probably get to it in about 4-6 months.
In the mean time, I thought I would get a handle on how ArduPilot works and build something that can do meaningful work on the surface of the water. A few people has approached me about building a low cost ASV that can take sonar recordings for later processing in the Reefmaster software.
I really liked @AntimatterCrusader 's hull, comprised of a Sun Dolphin Bali 6. It is cheaper than a fiberglass model boat hull and pretty rugged. Instead of a trolling motor, I'll be using 2x BlueRobotics T-200's with integrated Blue ESC's. I know it won't be as efficient as a vehicle with a rudder, but I needed something portable enough to fit in the back of my truck, so about 6ft was my limit. I'll also be using skid steering on my AUV, so it will be good practice for handling.
I intend to put all the electronics in removable Pelican cases and have three oriented in the boat. One in the back for navigation and power distribution to the thrusters, one in the middle for a large battery (still deciding on the chemistry), and one up forward for the Garmin chartplotter/sonar.
I design and order parts as I go, so updates will be a little on the slow side. First few steps will be getting the thrusters mounted and things situated in the navigation case. The cases I have right now are not final, they were just what I had laying around for the concept. I have quite a bit of room to work with.
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Did some more work on the NAV box over the past couple days. At least I'm up to the point where I can connect to it via my computer or tablet.
Next up will be getting power and signal to the thrusters and then mounting the box.
Thanks Jason, you definitely have the better product and I hope it sells well. If you ever get them in production and over to the USA, I'd buy one.
You are right, I haven't made the files public as I designed them for a commercial project however PM me and I will see what I can do for you. They would require some mods to fit your hull dimensions but that is easy enough. Anyway, here is my boat, powered by twin T200's. I hadn't connected the ball links between the servos and mounts when I took these photos. I actually rotated them 180deg so the servos are protected under the rim.
Images didn't load. Did it via an ipad, maybe that was the problem....
Looks well thought out and nicely made. Are you selling these? If so, where is your website so I can learn more?
@bigkahuna I was thinking of using those nylon cable glands too. Those would be easier to use if I need to disconnect the cable for whatever reason. I also have some BR cable penetrators.
@David Think something like these cable holders would work if I could get them the right size? I'm a bit against drilling holes in the hull...one more thing to go wrong.
Ya. Maybe running the cable up the side of the hull at the closest point with these types of fastener's would be a good option. I'm with you on not drilling holes. Although using 3M 5200 with thru hulls is bullet proof. The BR penetrators are great unless you need to pull off the thrusters for maintenance. Then what comes to mind is drilling a hole for the BR penetrators any different than using a small thru hull fitting.
Regards,
David R. Boulanger
Thrusters mounted. I used two ends of an HDPE cutting board and trimmed to fit and then glued them to the hull with marine epoxy. Not the most elegant solution, but they aren't going anywhere and I've maintained hull integrity. Everything will be repainted probably a light grey for the hull when I'm done.
Any ideas on how to secure the wires coming to the stern and eventually into the NAV box?
Kevin, Although I hate drilling holes in a hull you could use a couple of small thru hulls with some stiff rubber hose attached so that the opening was way above the waterline. The most important thing is probably just to make sure they can't flop around when under way. Its amazing the amount of drag that can be created by something small that's not firmly attached.
Regards,
David R. Boulanger
@Kevin - Why not use a couple nylon cable glands? Just be sure to mount them on the topside so you don't have to worry about a hull penetration.