Sorry for slow response!
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Agree on the longevity / durability concerns on an inflatable version. I think we could re-use the first surfer’s board, panels, radar reflector, etc. where applicable (?) I’m all for maximizing our power generation capacity though - many small asvs use small wind turbines…
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As for battery, I’d think ballasting the vehicle with 18650 cells would be awesome. I’m aware of a pack design we could lay hands on that fits nicely in 3" compartment, and ~doubles capacity in same volume of the green 4S hobbyking lipo you know from bluerov2. 6 or 10 of these would give our vehicle serious capacity!
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I can throw some stuff in cad (go sign up for onshape.com if you haven’t already to access) - but to summarize my general structure idea - A single long 3" tube or perhaps 2 such tubes held in a frame as you have pictured, or even up against the board itself! If run on centerline, it should prevent flip-over in anything but the craziest sea state.
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I think an m200 could spin a trolling motor prop, but I don’t know how well… I’ve got shaft couplings and a jig for attaching m4 props to the BR line of motors, so perhaps we could use some exotic RC boat prop - if metal we could even file and sharpen the blades. Placing it at the rear of the enclosure should also help, as you pictured. I’ve never seen a trolling motor prop handle swamps or some seaweed 100% successfully, but hope to be impressed.
The Catalina sea ranch would really love to have monitoring of the area for other vessels. They have an AIS receiving system setup, and the Nomad buoy transmits it’s location for large vessels, but monitoring for tampering, buoy loss, boat activity etc. is the current desire. A third (underwater!) camera should join the first to on the Nomad’s update system soon- theres no reason a roaming, ASV camera couldn’t be implemented on the same site! Throwing a Celsius temp sensor and perhaps a cyclops fluorometer I have for testing on it might enable the platform to have some scientific / biological justifications as well. The tricky part on this would be sensor drivers…
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As for electronics infrastructure - I’m thinking the vehicle uses a pixhawk + rasperry pi 3. We can use the 900mhz radios common to planes/copters to get 1km+ telemetry link easily - and for more than the $20 that’d cost other systems offer as far as 40km range! The Nomad would host an instance of Mavproxy to forward mavlink communications from the pixhawk to the internet, for remote interface with our own local instance of QGC. Some vpn action might become necessary here.
Do you know from your rover / ASV experience with pixhawk if looping missions are possible? I think they are… a patrol back and forth between 2 or eventually 4 or more waypoints would be a good demonstration mission I think - obviously a position hold mode activating if batteries run low or by default at night?
Meanwhile, when in range of the Nomad’s wifi signal, the Rasperry Pi could handle upload of patrol pictures, logged sensor data, etc. It would simply join the network and upload files to a local ftp for viewing. Having installed a few cameras so far, setting one up to play nice with the Pi is trivial - and I don’t think we’d need more than a few simple scripts to handle logging and upload on connection.
The only other electrical system I can think of in this project would be the charge controller. Rusty did some neat things with the SolarSurfer - but if nothing else some off the shelf mpt solar charge controllers with load connection should handle this easily - the tricky part is finding ones compatible with our 4S voltage - or anything not lead acid for that matter… Definitely a point to research.
I think the single case in the middle makes sense - with an antenna mast next to it to minimize co-ax cable run length. A radar reflector could stick up on the tail?
How about both above and below water cams!?!?
We should pick a weekend to play with the components on a table!
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-T
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