Control and Estimation for Effective Stationkeeping Operations in Sea-ice

November 03, 2017, Webb 1100

Roger Skjetne

NTNU, Marine Technology

Abstract

I will in this talk give an introduction to marine operations in Arctic drifting sea ice, and some associated control and estimation problems to make such operations more effective and safe. The presentation will discuss some problems and results from a project called Arctic DP: «Safe and green dynamic positioning operations of offshore vessels in an arctic environment» that was awarded by the Research Council of Norway in 2010 to our research group and industry partners Kongsberg Maritime, Statoil, and DNV GL. We were, in this project, looking into new control strategies for dynamic positioning (DP) systems to compensate rapidly varying loads on the DP vessel from drifting sea-ice in an Arctic stationkeeping operation. Particularly, we have studied different methods for using accelerometers and angular rate sensors (IMUs) to give us better estimates of the ice loads to be counteracted. In addition we have been looking into the Ice Management system that is used to protect the stationkeeping vessel from too large loads, including how to provide better local surveillance of the drifting sea-ice and icebergs. This is done by using available means of instrumentation and mobile sensor platforms in combination with shipboard sensors, and image processing algorithms to extract useful information from sea-ice images. Such sensory information of the Arctic ice environment can then potentially be used in future Ice Management decision support systems and possible algorithms to better guide and control the icebreakers and protected stationkeeping vessel.

Speaker's Bio

Professor Roger Skjetne received his MSc degree in 2000 from the University of California at Santa Barbara (UCSB) and his PhD degree in 2005 from the Norwegian University of Science and Technology (NTNU) on control engineering. He holds an Exxon Mobil prize for his PhD thesis at NTNU. Prior to his studies, he worked as a certified electrician for Aker Elektro AS on numerous oil installations for the North Sea, and in 2004-2009 he was employed in Marine Cybernetics AS, working on Hardware-In-the-Loop simulation for testing marine control systems. From August 2009 he has held the Kongsberg Maritime chair of Professor in Marine Control Engineering at the Department of Marine Technology at NTNU. His research interests are within dynamic positioning of marine vessels, Arctic stationkeeping and Ice Management systems, control of shipboard hybrid electric power systems, nonlinear motion control of marine vehicles, and autonomous marine robots.