Blar i NTNU Open på forfatter "Fossen, Thor I."
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A Machine Learning Approach for Estimating Air Data Parameters
Borup, Kasper Trolle; Fossen, Thor I.; Johansen, Tor Arne (Journal article; Peer reviewed, 2019)This paper presents a method for estimating the air data parameters for a small fixed-wing, unmanned aerial vehicle (UAV) using an arrangement of low-cost MEMS-based pressure sensors embedded in the surface of the UAV. The ... -
A Neural Network Approach to Control Allocation of Ships for Dynamic Positioning
Skulstad, Robert; Li, Guoyuan; Zhang, Houxiang; Fossen, Thor I. (Journal article; Peer reviewed, 2018)Dynamic Positioning (DP) of ships is a control mode that seeks to maintain a specific position (stationkeeping) or perform low-speed maneuvers. In this paper, a static Neural Network (NN) is proposed for control allocation ... -
A UAV Ice Tracking Framework for Autonomous Sea Ice Management
Leira, Frederik Stendahl; Johansen, Tor Arne; Fossen, Thor I. (Chapter; Peer reviewed, 2017)This paper describes an unmanned aerial vehicle (UAV) ice tracking framework for use in sea ice management applications. The framework is intended to be used in an ice management scenario where the UAV should detect and ... -
A Uniformly Semiglobally Exponentially Stable Nonlinear Observer for GNSS- and Camera-Aided Inertial Navigation
Fusini, Lorenzo; Fossen, Thor I.; Johansen, Tor Arne (Journal article, 2014)In this paper a nonlinear observer for estimation of position, velocity, acceleration, attitude and gyro bias of an Unmanned Aerial Vehicle (UAV) is proposed. The sensor suite consists of an Inertial Measurement Unit (IMU), ... -
A virtual vertical reference concept for aided inertial navigation at the sea surface
Bryne, Torleiv Håland; Rogne, Robert Harald; Fossen, Thor I.; Johansen, Tor Arne (Journal article; Peer reviewed, 2017)When trying to capture the heaving motion of a marine vessel in waves, conventional position references such as global navigation satellite systems fall short in many cases. Because of design and satellite geometry, the ... -
An Adaptive Line-of-sight (ALOS) Guidance Law for Path Following of Aircraft and Marine Craft
Fossen, Thor I. (Journal article; Peer reviewed, 2023) -
Aerodynamic modeling of the Skywalker X8 Fixed-Wing Unmanned Aerial Vehicle
Gryte, Kristoffer; Hann, Richard; Alam, Mushfiqul; Rohac, Jan; Johansen, Tor Arne; Fossen, Thor I. (Chapter, 2018)With advanced control, estimation and simulation requirements in unmanned aerial systems comes the need for sophisticated aerodynamic models. This paper reviews two common means for establishing such models; numerical ... -
Attitude Estimation by Multiplicative eXogenous Kalman Filter
Stovner, Bård Nagy; Johansen, Tor Arne; Fossen, Thor I.; Schjølberg, Ingrid (Journal article, 2018)This paper presents a novel attitude estimator called the multiplicative exogenous Kalman filter. The estimator inherits the stability properties of a nonlinear observer and the near-optimal steady-state performance of the ... -
Authenticated Encryption Methods for Feedback Control Systems
Solnør, Petter (Master thesis, 2021)Tilbakekoplingssystemer krever at signaler sendes mellom sensorer, tilstandsestimatorer, regulatorer og aktuatorer. Disse signalene er sårbare for tyvlytting, som gjør at uautoriserte aktører kan få kjennskap til potensielt ... -
Automatic detection, classification and tracking of objects in the ocean surface from UAVs using a thermal camera
Leira, Frederik Stendahl; Johansen, Tor Arne; Fossen, Thor I. (Journal article; Peer reviewed, 2015)The use of unmanned aerial vehicles (UAVs) that can operate autonomously in dynamic and dangerous operational environments are becoming increasingly common. In such operations, object detection, classification and tracking ... -
Autonomous Docking Control System for the Otter USV: A Machine Learning Approach
Bjering Strand, Henrik (Master thesis, 2020)Denne masteroppgaven utforsker muligheten for å bruke dyp forsterkende læring (eng. deep reinforcement learning, DRL) til å utvikle et autonomt dokkingsystem for en underaktuert overflatefarkost. Autonome marine fartøy er ... -
Autonomous recovery of a fixed-wing UAV using a net suspended by two multirotor UAVs
Klausen, Kristian; Fossen, Thor I.; Johansen, Tor Arne (Journal article; Peer reviewed, 2018)This article presents a novel recovery method for fixed‐wing unmanned aerial vehicles (UAVs), aimed at enabling operations from marine vessels. Instead of using the conventional method of using a fixed net on the ship deck, ... -
A Co-operative Hybrid Model For Ship Motion Prediction
Skulstad, Robert; Li, Guoyuan; Fossen, Thor I.; Wang, Tongtong; Zhang, Houxiang (Peer reviewed; Journal article, 2021)Dynamic models of ships have been widely used for model-based control and short-term prediction in the past. Identifying the parameters of such models has mainly been done through scaled model tests, full scale tests or ... -
Collaborative Collision Avoidance for Autonomous Ships Using Informed Scenario-Based Model Predictive Control
Akdag, Melih; Fossen, Thor I.; Johansen, Tor Arne (Peer reviewed; Journal article, 2022)There exist several collision avoidance algorithms for autonomous ships. But the majority of them do not utilize information about other ships’ intentions, except for observed position and velocity. As the attention for ... -
Continuous-Curvature Path Generation using Fermat's Spiral
Lekkas, Anastasios; Dahl, Andreas R; Breivik, Morten; Fossen, Thor I. (Journal article; Peer reviewed, 2013)This paper proposes a novel methodology, based on Fermat's spiral (FS), for constructing curvature-continuous parametric paths in a plane. FS has a zero curvature at its origin, a property that allows it to be connected ... -
Cooperative Control for Multirotors Transporting an Unknown Suspended Load under Environmental Disturbances
Klausen, Kristian; Meissen, Chris; Fossen, Thor I.; Arcak, Murat; Johansen, Tor Arne (Journal article; Peer reviewed, 2019)In this paper, we develop a cooperative control algorithm for a group of multirotor unmanned aerial vehicles (UAVs) transporting a suspended payload of unknown mass. In addition, the vehicles are subjected to unknown ... -
Cyber-resilient Aided Inertial Navigation: Applications to Ships and Unmanned Surface Vehicles
Volden, Øystein (Doctoral theses at NTNU;2023:15, Doctoral thesis, 2023)With the recent advancement in maritime autonomy, the autonomous ship market is predicted to cut costs through more efficient operation of uncrewed ships and surface vehicles, followed by a reduction in associated construction ... -
Data-Based Modelling of Ships for Motion Prediction and Control Allocation
Skulstad, Robert (Doctoral theses at NTNU;2021:383, Doctoral thesis, 2021)Vessels operating on the surface of the ocean are exposed to an array of disturbances. These may come in terms of environmental disturbances, but may also come from signal loss. Modelling the behaviour of ships using ... -
Dead Reckoning of a Fixed-Wing UAV with Inertial Navigation Aided by Optical Flow
Fusini, Lorenzo; Johansen, Tor Arne; Fossen, Thor I. (Chapter; Peer reviewed, 2017)This paper provides experimental results for dead reckoning of a fixed-wing UAV using a nonlinear observer (NLO) and a more recent tool called eXogenous Kalman Filter (XKF), which uses the NLO itself as a first-stage filter. ... -
Dead Reckoning of Dynamically Positioned Ships: Using an Efficient Recurrent Neural Network
Skulstad, Robert; Li, Guoyuan; Fossen, Thor I.; Vik, Bjørnar; Zhang, Houxiang (Journal article; Peer reviewed, 2019)When a ship experiences a loss of position reference systems, its navigation system typically enters a mode known as dead reckoning (DR) to maintain an estimate of its position. Commercial systems perform this task using ...