Akula: a 2m autonomous model submarine

I published the first video of this project on October 16, 2026. It doesn't show a finished subsystem. It's the map: what I'm building, what exists today, and what I haven't figured out yet.

The hull is 16 3D-printed parts, two meters long when assembled. They're still rough. They're also supposed to let water in. The outer hull is free-flooding by design, and the electronics will sit in a separate dry container inside. That container is still in design, and it's where most of the waterproofing work will happen. Design depth is 10 meters.

Propulsion is two counter-rotating propellers, each on its own brushed motor. The sonar is a rotating active sonar I'm building from scratch; so far only an early test board has given a repeatable return in a bucket, with range not confirmed. Software is planned around ArduRover (boat mode) and ROS 2, but nothing runs on the vehicle yet.

The video also covers the hardest part of the power system: a small gasoline engine that charges the batteries inside a vehicle that's meant to spend its time underwater. Off camera, the engine already drives a brushless motor as a generator on a test bench in my apartment. So far it makes about 400 W. Under load, the generator's back torque seems to hold the engine's RPM down, so next I'm adding a belt reduction. Getting all of it into the hull, with a snorkel and cooling, is a separate problem I haven't solved yet.

Some context: I spent about twenty years in software before this, and I came back to hardware in 2024. A lot of this is new to me. If you've built underwater vehicles and see something wrong, tell me in the comments. I'd rather hear it now.

Next up: the pneumatic ballast system on a test bench. A tank floods with water and blows clear. The boat doesn't dive in that test; a full dive comes much later, once the hull, motors and ballast work together.

Video: 
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