No Rudder Needed: This Boat Steers by Shifting Weight express
A person in a boat turns by shifting their body weight. An unmanned vessel uses the same trick: a sliding weight inside the hull does the steering. Its movement is controlled by a neural network, anticipating the chaos of waves and gusts of wind. The propeller pushes the boat forward, while the weight shifts balance — like moving from one foot to the other. The sharper the shift, the tighter the turn. A lightweight carbon fiber hull makes the response instant.
This rudderless approach simplifies construction and boosts reliability. Tests showed the boat stays on course with minimal error, dodging obstacles with centimeter precision.
Original abstract
as written by the authors arXiv:2607.12562
Addressing the control and maneuverability of surface vehicles with dynamically changing mass distributions is still an open problem. To solve the problem, we propose an intelligent controller for the path-following problem of a surface vehicle, which is controlled through mass distribution. This means that one of the control inputs is mass-centric. Specifically, we developed a Lyapunov-based nonlinear control scheme to enable an unmanned vessel to follow a smooth path according to a line-of-sight guidance law. The control inputs consist of the thrust force for forward motion and the position of a sliding mass that shifts the system's overall mass distribution. Artificial neural networks are employed to estimate unmodeled dynamics and external disturbances. Simulation results demonstrate the effectiveness of the proposed controller in guiding the vessel along the desired path with minimal error.
Large ships balance with hundreds of tons of water ballast, but the solid weight in this system reacts faster than the blink of an eye, and needs no pumps.