At Team aQuatonomous, we’re always striving to push the boundaries of autonomous aquatic systems. In this article, we dive into the mechanical design and engineering behind our latest vessel, affectionately titled “Nautical Disaster.” From crafting lightweight, stable pontoons to integrating advanced propulsion and waterproofing systems, every detail was meticulously designed to meet competition requirements and support ecological data collection. Join us as we explore the innovative process behind creating a vessel that’s as functional as it is futuristic.
The overarching design for the vessel was created with the goal of maximizing deck surface area and metacentric stability while minimizing mass. Lateral maneuverability was also taken into consideration. A dual-hull marine platform was determined to be the optimal design.
The full ASV design.
The size of the vessel was confined by the measurements outlined in the 2025 Roboboat Team Handbook which states that the vehicle cannot exceed six feet by three feet by three feet. The craft must also be large enough to be utilized as a tool for ecological data collection and therefore must be capable of supporting additional testing equipment should it be required. Finally, the vessel must be easily transported and therefore the two pontoons must be capable of separation and reattachment from the hull.
Each pontoon was built using a “skeleton” made of laser-cut plywood and 3D printed frames which were layered with closed cell foam boards. They were wrapped in 6 Oz fiberglass with 1-4 layers depending on how susceptible the location is to damage. The pontoons can support a maximum weight of 140lbs but are designed to be hydrodynamically optimal for a total weight of 55-70lbs.
The skeleton of one of the pontoons.
The two pontoons of the vessel, now with foam!
The fiberglassing process of the pontoons.
A sheet of 1.5-inch marine grade plywood cut to shape was used for the bridge with three M5 bolts fitted to threaded inserts on each side for a streamlined assembly/disassembly. Holes were placed at mounting locations across the hull with M4 bolts and wing nuts allowing for every component to be removed easily.
Electrical components are primarily housed in the electrical box, centered on the bridge for convenient connection to systems throughout the vessel. The box is fully waterproof, featuring O-rings and liquid-tight cord grips that allow wires to pass out of the container. Inside, there are two floors: one slightly elevated above the base to prevent water contact with components, and the other 2.4 inches higher to maximize available space. The second floor, made of transparent plexiglass, is easily removable.
Positioned immediately in front of the electrical box is the 3D-printed battery enclosure, which also contains a slightly elevated base to mitigate potential water damage. The camera is centrally mounted along the leading edge of the bridge, providing a complete and unobstructed view of the area ahead of the vessel. Positioned behind it, the Lidar is elevated to the same height as the electrical box, optimizing its ability to detect objects in a full 360-degree radius around the craft. Placed at the back, starboard corner of the bridge is the status light which indicates whether the vessel is driving automatically (green), driving manually (yellow) or completely stopped (red). It is connected to the bridge using a custom-designed plastic base.
The bridge of the vessel with all components mounted.
The primary factors dictating the team’s propulsion design were maneuverability, simplicity, ease of repair and safety. Each hull is fitted with a PVC tube running vertically through the stern enclosing a steering axle. A 3D-printed connection piece with an embedded shaft collar and strong friction fit is used to firmly attach T200 Blue Robotics Thrusters to their respective axles. On the surface of the pontoon, the steering shafts are connected to two STP-MTR-23055 SureStep stepper motors with a set of gears. The default gear ratio is 1:1 but could easily be altered should it be required. The thrusters are capable of 180 degrees of rotational motion which allows for exceptional maneuverability. Running parallel to the steering axle is a second through-hull hole for the thruster power cables. A plug is permanently attached to each cable enabling it to be removed while blocking water from the interior. To guarantee safety around the gear system, a clear plastic casing surrounds them and is only removed when the vessel is not in use. The entire propulsion system is completely removable.
The propulsion system on one of the two pontoons.
