Show simple item record

dc.contributor.advisorSkjetne, Rogernb_NO
dc.contributor.advisorKjerstad, Øivind Kårenb_NO
dc.contributor.authorTutturen, Svenn Arenb_NO
dc.date.accessioned2014-12-19T12:13:18Z
dc.date.available2014-12-19T12:13:18Z
dc.date.created2014-11-13nb_NO
dc.date.issued2014nb_NO
dc.identifier762925nb_NO
dc.identifierntnudaim:11556nb_NO
dc.identifier.urihttp://hdl.handle.net/11250/239251
dc.description.abstractThis thesis consists of three main parts. The first part of the master thesis looks at the identification of thruster dynamics and low speed ship dynamics. The relevant parameters identified are time constants and time delays in the system. Simple step tests are used for the identification. Different models for identification are suggested, both for uncoupled surge, sway, and yaw dynamics. Other test results, such as agility plots, DP 4 corner tests, and pure DP tests (stationkeeping) are reported. All the results are to be compared to similar tests performed after R/V Gunnerus has a retrofit of the thruster system.The second part discusses another problem, and that is the topic of numerically estimat- ing the body frame position of the GNSS and MRU sensors. For the GNSS position an Luenberger observer design and an adaptive scheme are proposed and analyzed. The es- timation designs are tested using numerical simulations and experimental data from the Gunnerus sea trials. A similar Luenberger observer is proposed for the MRU positions, and experimental data from the sea trials are used to test the observer.The third part discusses a hybrid augmentation of integral action. The motivation is a DP system, where typically the integral action is tuned very low to avoid oscillations due to the integral action. When there is a sudden load change, such as a ice load that hits the vessel, or if a mooring wire snaps, then a hybrid update augmentation could be useful, to speed up the convergence of the integral action. The update law is a linear update law based on the error in the states (the velocity for the DP system). The augmentation can significantly improve performance, especially for very large disturbance changes.nb_NO
dc.languageengnb_NO
dc.publisherInstitutt for marin teknikknb_NO
dc.subjectntnudaim:11556no_NO
dc.subjectMTMART Marin teknikkno_NO
dc.subjectMarin kybernetikkno_NO
dc.titleTopics in dynamic positioning: System identification, GNSS and MRU lever arm estimation, and hybrid integral actionnb_NO
dc.typeMaster thesisnb_NO
dc.source.pagenumber114nb_NO
dc.contributor.departmentNorges teknisk-naturvitenskapelige universitet, Fakultet for ingeniørvitenskap og teknologi, Institutt for marin teknikknb_NO


Files in this item

Thumbnail
Thumbnail
Thumbnail

This item appears in the following Collection(s)

Show simple item record