Modeling, Simulation and Control for Marine Crane Operations

Abstract

Marine cranes play an important part in offshore operations. They are expected to perform awide range of different tasks, such as handling the load safely offshore. Nowadays, the offshoreoil fields and wind farms are detected and developed, thus more and more offshore platforms arebuilt. The scale and capacity of crane vessels are developing rapidly to fulfill the construction needof offshore platforms and offshore wind farms. Heavy crane, placed on-board vessel, is affected byvessel motions induced by environmental forces such as wind, waves and current, and vice versa.Therefore, the investigation of coupled dynamics between heavy crane and vessel, position controlof vessel, and heave compensation is important and needs to be analyzed thoroughly. This masterproject focus on Modeling, Simulation and Control for Marine Crane Operations. The model wasdeveloped in Matlab, Simulink and Simscape Multi-body.It is several ways to developed Control designs for an offshore crane, but in this thesis the controltask only concerns position control of the crane. The main goal is to determine the most suitablecontroller design for this tasks.A trajectory planning scheme is developed that can damp out unexpected payload swing. Craneend-effector is controlled to follow a trajectory planning scheme in x-direction with as small er-ror between desired and measured position as possible. The desired position is a movement from23.15m which is the x-coordinate when the crane arm is fully extended, to 15m.