  We propose a method for performing automatic docking of a small autonomous
surface vehicle (ASV) by interconnecting an optimization-based trajectory
planner with a dynamic positioning (DP) controller for trajectory tracking. The
trajectory planner provides collision-free trajectories by considering a map
with static obstacles, and produces feasible trajectories through inclusion of
a mathematical model of the ASV and its actuators. The DP controller tracks the
time-parametrized position, velocity and acceleration produced by the
trajectory planner using proportional-integral-derivative feedback with
velocity and acceleration feed forward. The method's performance is tested on a
small ASV in confined waters in Trondheim, Norway. The ASV performs
collision-free docking maneuvers with respect to static obstacles when tracking
the generated reference trajectories and achieves successful docking.
