Numerical investigation of the manoeuvring motions and trajectory tracking of a KVLCC2 tanker using PID controller in regular waves

An autopilot based on a PID control technique is incorporated in a 6DOF unified seakeeping and manoeuvring numerical model of a ship in a seaway. A crude oil carrier (KVLCC2) prototype is used in the study. The surge, sway and yaw are assumed to be slowly varying motions and the heave, roll and pitch respond to the rapidly varying wave forces. The second order wave mean drift forces act on the horizontal motions. For heave, roll and pitch, the Froude-Krylov forces and the restoring are calculated for the exact wetted surface area for each time step. The hull resistance and the control forces are calculated based on an empirical data available in the existing literature. The reference heading is obtained from Line Of Sight (LOS) algorithm using way-points. The effectiveness of autopilot developed based on PID controller is studied in regular waves.