Dynamic positioning systems: An experimental analysis of sliding mode control

• Published in: Control engineering practice Vol. 18; no. 10; pp. 1121 - 1132
• Main Authors: Tannuri, E.A., Agostinho, A.C., Morishita, H.M., Moratelli, L.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-10-2010; Elsevier
• Subjects: Applied sciences; Computer science; control theory; systems; Control system analysis; Control system synthesis; Control theory. Systems; Controllers; Dynamical systems; Dynamics; Exact sciences and technology; Ground, air and sea transportation, marine construction; Marine and water way transportation and traffic; Marine systems; Nonlinear control; Nonlinear dynamics; Nonlinearity; PID controllers; Robust control; Sliding mode control; Tuning; Vessels; Robust control; PID controllers; Sliding mode control; Nonlinear control; Marine systems; Variable structure control; Sliding mode; Position control; Non linear control; Dynamical system; Gain scheduling; Dynamic conditions; Extended Kalman filter; Dynamic positioning; Ship; Differential integral proportional control; Dynamic load
• ISSN: 0967-0661; 1873-6939
• DOI: 10.1016/j.conengprac.2010.06.007

Vessel dynamic positioning (DP) systems are based on conventional PID-type controllers and an extended Kalman filter. However, they present a difficult tuning procedure, and the closed-loop performance varies with environmental or loading conditions since the dynamics of the vessel are eminently nonlinear. Gain scheduling is normally used to address the nonlinearity of the system. To overcome these problems, a sliding mode control was evaluated. This controller is robust to variations in environmental and loading conditions, it maintains performance and stability for a large range of conditions, and presents an easy tuning methodology. The performance of the controller was evaluated numerically and experimentally in order to address its effectiveness. The results are compared with those obtained from conventional PID controller.