Unmanned sailboat trajectory tracking method based on model predictive control

Objective An unmanned sailboat trajectory tracking method based on model predictive control (MPC) is proposed for the collaborative operation of unmanned sailboats in surface/underwater cross-domain heterogeneous marine robotics scenarios.

Methods Using the unmanned sailboat Seagull, we establish its dynamics and kinematics models, analyze its dynamic characteristics and actuator constraints, construct the MPC objective function and system constraints, convert the trajectory tracking problem of the unmanned sailboat into an optimization problem and carry out simulation and experimental validation using Matlab software.

Results The simulation results show that compared with the sail-rudder separate PID trajectory tracking control method, the proposed sail-rudder joint MPC control method is more convenient for adding constraints. It can converge to the specified trajectory faster with smaller trajectory tracking error under a changing wind direction and realize upwind zigzag sailing.

Conclusions The results of this study can provide new ideas for the sail and rudder control of unmanned sailboats, improve the trajectory tracking ability and provide a further technical guarantee for the efficient collaborative operation of unmanned sailboats and AUVs.