The concept is guided by the ‘good enough’ principle and this platform is intended for entry level roboticists, students, marine researchers, etc. It is intended to be modular and simple to construct and attach/detach from basically anything small and floating (think boogie boards, surfboards, kayaks, etc.).
I am currently using a Pixhawk 2.4.8 and the next build will probably use a Holybro Pixhawk 4, since I have one of those gathering dust. For Rx/Tx, I am using FrSky X8R and X9 Lite. For propulsion, I am using 2 x Blue Robotics T200 thrusters and their Basic ESCs. All the electronics are housed in an IP65 junction box and powered by a single 4S 5000 mAh LiPo, though I ordered LiPo decouplers so I can run 2 batteries in parallel and hot-swap them. The current build is mounted on an old boogie board with a 3D-printed bracket.
I am writing up a full build guide and BOM, both of which will be open source.
For now, enjoy this video and some pics