Browsing NTNU Open by Author "Caharija, Walter"
Now showing items 1-19 of 19
-
Autonomous Monitoring and Inspection Operations with UUVs in Fish Farms
Kelasidi, Eleni; Su, Biao; Caharija, Walter; Føre, Martin; Pedersen, Magnus Oshaug; Frank, Kevin (Peer reviewed; Journal article, 2022)In this study, a general control framework for autonomous operations in highly complex and dynamically changing environments such as fish farms is proposed and experimentally validated. Since fish farms feature an environment ... -
Autonomous Monitoring and Inspection Operations with UUVs in Fish Farms
Kelasidi, Eleni; Su, Biao; Caharija, Walter; Føre, Martin; Pedersen, Magnus Oshaug; Frank, Kevin (Peer reviewed; Journal article, 2022)In this study, a general control framework for autonomous operations in highly complex and dynamically changing environments such as fish farms is proposed and experimentally validated. Since fish farms feature an environment ... -
Autonomous ROV inspections of aquaculture net pens using DVL
Amundsen, Herman Biørn; Caharija, Walter; Pettersen, Kristin Ytterstad (Peer reviewed; Journal article, 2021)This article presents a method for guiding a remotely operated vehicle (ROV) to autonomously traverse an aquaculture net pen. The method is based on measurements from a Doppler velocity log (DVL) and uses the measured ... -
Dynamic Bias for RF Class A Power Amplifiers
Caharija, Walter (Master thesis, 2009)This thesis focuses on class A radio frequency power amplifiers in dynamic supply modulation architectures (dynamic bias). These are promising efficiency enhancement techniques where the device is driven harder by varying ... -
Estimation of Structural Geometry: Sensors and Software to Generate Real-time Maps of Structural Geometry in Fish Farms
Nybø, Gaute (Master thesis, 2019)Denne oppgaven er en del av et forskningsprosjekt kalt Artifex, på SINTEF Ocean AS. Prosjektet tar sikte på å utvikle et generelt system som brukes til fjernoperasjoner på fiskeanlegg for å redusere behovet for tilstedeværende ... -
Guidance and maneuvering principles for autonomous ROV missions in an aquaculture context
Drønen, Vilde Økland (Master thesis, 2021)Bidraget fra denne masteroppgaven er et nytt guidningssystem for navigering av fjernstyrte kjøretøy (ROVer) basert på en konstant referansemodell kombinert med veipunktfølging. Dette bidraget er et resultat av ønsket om å ... -
Implementation and Comparison of Nonlinear State of Charge Estimators using Equivalent Circuit Models for Two Lithium-Ion Battery Cell Chemistries
Svendsen, Daniel Dreyer (Master thesis, 2023)Litium-ion-batterier blir omfattende brukt som en energilagringsløsning. De gir fordeler som lav vekt, høy energitetthet og holdbarhet, og kan være avgjørende for ̊a oppn ̊a kli- manøytralitet. Kontinuerlig optimalisering ... -
Integral Line-of-Sight Guidance and Control of Underactuated Marine Vehicles
Caharija, Walter (Doktoravhandlinger ved NTNU, 1503-8181; 2014:316, Doctoral thesis, 2014)This dissertation presents an extensive analysis of the integral line-of-sight (ILOS) guidance method for path following tasks of underactuated marine vessels and vehicles, operating on and below the sea surface. It is ... -
Integral Line-of-Sight Guidance and Control of Underactuated Marine Vehicles: Theory, Simulations and Experiments
Caharija, Walter; Pettersen, Kristin Ytterstad; Bibuli, Marco; Calado, Pável; Zereik, Enrica; Braga, Jose; Gravdahl, Jan Tommy; Sørensen, Asgeir Johan; Milovanovic, Milan; Bruzzone, Gabriele (Journal article; Peer reviewed, 2016)This paper presents an extensive analysis of the integral line-of-sight (ILOS) guidance method for path-following tasks of underactuated marine vehicles, operating on and below the sea surface. It is shown that due to the ... -
Integral Line-of-Sight Guidance of Underwater Vehicles Without Neutral Buoyancy
Caharija, Walter; Syre Wiig, Martin; Krogstad, Thomas Røbekk; Pettersen, Kristin Ytterstad (Journal article; Peer reviewed, 2016)This paper analyzes an integral line-of-sight guidance law applied to an underac-tuated underwater vehicle. The vehicle is rigorously modeled in 5 degrees of freedom usingphysical principles, and it is ... -
Online Parameter Estimation for State of Health and State of Charge Estimation with Joint and Dual Extended Kalman Filters
Halse, Kjetil (Master thesis, 2024)I de siste tiårene har litium-ion-batterier (LIB) blitt den ledende teknologien innen energilagring. På grunn av dens mange gode egenskaper blir de implementert i en rekke ulike applikasjoner. Dessverre er ikke batteriene ... -
Path Following Control of Underactuated Surface Vessels in the Presence of Multiple Disturbances
Caharija, Walter; Sørensen, Asgeir Johan; Pettersen, Kristin Ytterstad; Greco, Marilena; Gravdahl, Jan Tommy (Chapter, 2019)An integral version of the line-of-sight guidance method is shown to compensate for both kinematic and dynamic disturbances generated by wind, waves and sea currents. The guidance law is designed for path following tasks ... -
Path Following of Underactuated Autonomous Underwater Vehicles in the Presence of Ocean Currents
Caharija, Walter; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy; Børhaug, Even (Journal article; Peer reviewed, 2012)A control strategy allowing underactuated underwater vehicles to accomplish 3D straight line path following tasks in the presence of ocean currents is developed. The ocean current is considered constant, irrotational and ... -
Path Following of Underactuated Marine Surface Vessels in the Presence of Unknown Ocean Currents
Moe, Signe; Caharija, Walter; Pettersen, Kristin Ytterstad; Schjølberg, Ingrid (Journal article; Peer reviewed, 2014)This paper considers path following control of snake robots and has two contributions. The first contribution is a description of how a straight line path following controller previously proposed by the authors can be ... -
Robust adaptive backstepping DP control of ROVs
Ohrem, Sveinung Johan; Amundsen, Herman Biørn; Caharija, Walter; Holden, Christian (Peer reviewed; Journal article, 2022)Dynamic positioning is an important control feature for an underwater remotely operated vehicle. This paper presents a nonlinear dynamic positioning controller suited for application to vehicles with model uncertainties, ... -
Robust Nonlinear ROV Motion Control for Autonomous Inspections of Aquaculture Net Pens
Amundsen, Herman Biørn (Master thesis, 2020)Denne oppgaven presenterer en metode for a kontrollere en fjernstyrt undervannsbåt (ROV) til å autonomt traversere og inspisere en not for bruk i fiskeoppdrett. Metoden er basert på Doppler velocity log- (DVL) målinger, ... -
Semiglobal exponential stability of a counter-current and co-current guidance scheme
Caharija, Walter; Grøtli, Esten Ingar; Pettersen, Kristin Ytterstad (Journal article; Peer reviewed, 2018)A control technique for counter-current and co-current guidance of underactuated marine vehicles is revisited and stronger stability properties are shown. In particular, the stronger property of uniform semiglobal exponential ... -
Towards Autonomous ROVs in Aquaculture: Implementation of Autonomous Mission Control for Unmanned Operations
Karlsen, Henning Ødeby (Master thesis, 2021)I denne oppgaven utformes og implementeres et autonomt system for oppdragskontroll av en autonom ROV, slik at den er i stand til å utføre autonome undervanns- inspeksjons-, vedlikeholds- og reparasjonsoppdrag innenfor ... -
Underwater Pose Graph SLAM with DVL-Enhanced Visual Loop Closure for Future Aquaculture
Straume Haugland, Kyrre (Master thesis, 2021)Denne masteroppgaven presenterer en metode for å løse lokaliserings- og kartleggingsproblemet (SLAM) for en fjernstyrt undervannsfarkost (ROV) i en merde. Dette problemet er løst ved å bruke en poseringsgraf-SLAM-algoritme ...