The base design is simple, the hulls are made from 2 PVC tubes sealed with end-caps. 3D printed nose cones, filled with self expanding foam are glued to the front end of the tubes. Then some lengths of aluminum, hose clamps and 3D printed parts, together with SS bolts, hold it all together. A watertight, rectangular enclosure houses the electronics.

The first design iteration is to remote control the boat using a standard RC control unit, to test motor performance and maneuverability and general sea-worthiness. 

This is what the electronics enclosure looks like:

It contains two sets of batteries, one for the main central thruster and the other for the side steering motors. There is an ESC for the central thruster which has a fan and 5V outlet that powers an Arduino Mega. The Mega runs some relatively simply code that takes the PWM signals from the RC unit and converts them to signals that control the side steering motors, via a L298N motor controller. The RC PWM channel that controls the brushless main thruster, goes directly from the RC receiver to the ESC, the Mega is not involved in controlling the main thruster. 

Apart from that there are a couple of switches to turn each of the two circuits on, a fuse for each circuit, and a perforated 3D printed base-board that keeps the electronics off the bottom of the enclosure and also doubles as a convenient way to attach the components using cable ties.

The above set of components is for basic testing only. The plan is to replace the Mega with an Arduino Q (which has both microcontroller and single board computer processor) - this will provide a much more flexible way to code the autonomous functions into the system. There will also be a GPS, IMU and radio added. The radio will be used as a backup control method and also for sending real-time data to the shore.

The enclosure itself (purchased from the local hardware store) seems to have a really good seal with strong clips and IP68 rating so it should keep the electronics dry even in the event of a capsize. If required, multiple enclosures can be stacked on top of each other for to allow for more batteries or larger payloads.

The boat has been designed with possibly capsizing in mind with a self righting add-on in the works. This will take the form of a topside sealed PVC tube (visible in the video and the photos) and a weighted keel. Together they should allow the boat to self right if it capsizes in heavy sees.

I am starting to create a parts list, and will also upload STL files for all 3D printed parts soon, and eventually full build instructions will also be added.