Asv control policies trained in simulation transfer directly to real boats

Sim-to-Real RL for ASVs using SysID

Robotics

Summary

Controlling autonomous boats in changing water conditions is hard, and teaching them using computer simulations usually takes a lot of detailed water and vehicle data. The authors created a system that only needs a simple 3D model of the boat and some short real-world trial runs to estimate how the boat moves and its engine power. They then train control strategies entirely in simulation, which work on the real boat right away without extra tuning. This makes it easier and faster to develop smart controllers for autonomous surface vehicles.

What this means in practice

Authors

Cody Sheltraw, Tsimafei Lazouski, Maani Ghaffari, Alan Papalia

Abstract

Autonomous Surface Vehicles (ASVs) operating in dynamic marine environments require robust control policies for tasks such as path following and station keeping, making reinforcement learning (RL) a promising alternative to classical controllers. However, existing ASV simulators rarely support parallel environments for RL training. Such existing simulators require accurate hydrodynamic modeling from computational fluid dynamics solvers or towing tank tests for setting hydrodynamic parameters to address the sim-to-real gap. To address these challenges, we present an ASV simulator and accompanying pipeline that enables training policies starting from unknown vehicle dynamics. Our framework uses only a CAD model and brief set of open-water field trajectories for approximating and refining both hydrodynamic and thruster parameters. Real-world deployments on a BlueBoat ASV demonstrate successful zero-shot sim-to-real transfer in path following and station-keeping tasks without prior hydrodynamic and propeller information.