Analysis of Offshore Knuckle Boom Crane - Part Two: Motion Control

In this paper design of electro-hydraulic motion control systems for oshore knuckle boom cranes is discussed. The inuence of the control valve bandwidth along with the ramp time for the control signal are investigated both analytically with simplied system models and numerically with an experimentally veried crane model. The results of both types of investigations are related to general design rules for selection of control valves and ramp times and the relevance of these design rules is discussed. Generally, they are useful but may be too conservative for oshore knuckle boom cranes. However, as demonstrated in the paper, the only proper way to determine this is to evaluate the motion control system design by means of simulation.