• 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 ...
    • Aided Inertial Navigation of Small Unmanned Aerial Vehicles Using an Ultra-Wideband Real Time Localization System 

      Cisek, Krzysztof; Gryte, Kristoffer; Bryne, Torleiv Håland; Johansen, Tor Arne (Journal article; Peer reviewed, 2018)
      This paper presents an ultra-wideband (UWB) radio aided inertial navigation system (INS), estimating position, velocity and attitude (PVA), based on a low-cost microelectro-mechanical system (MEMS) Inertial Measurement ...
    • Autonomous ballistic airdrop of objects from a small fixed-wing unmanned aerial vehicle 

      Mathisen, Siri Gulaker; Leira, Frederik Stendahl; Helgesen, Håkon Hagen; Gryte, Kristoffer; Johansen, Tor Arne (Peer reviewed; Journal article, 2020)
      Autonomous airdrop is a useful basic operation for a fixed-wing unmanned aerial system. Being able to deliver an object to a known target position extends operational range without risking human lives, but is still limited ...
    • Autonomous Landing of Fixed-Wing UAV in Net suspended by Multirotor UAVs - A Fixed-Wing Landing System 

      Nevstad, Sigurd Olav (Master thesis, 2016)
      This thesis presents an autonomous landing system designed for an fixed-wing unmanned aerial vehicle (UAV) to land in a net suspended by multirotor UAVs. Ordinary landing of an fixed-wing UAV usually involves landing on a ...
    • Estimation of UAV Position, Velocity and Attitude Using Tightly Coupled Integration of IMU and a Dual GNSS Receiver Setup 

      Sollie, Martin Lysvand (Master thesis, 2018)
      Increasing use of UAVs in high-precision applications, such as georeferencing and photogrammetry, increases the requirements on the accuracy of the estimated position, velocity and attitude of the vehicle. Commercial systems ...
    • Field Test Results of GNSS-denied Inertial Navigation aided by Phased-array Radio Systems for UAVs 

      Gryte, Kristoffer; Bryne, Torleiv Håland; Albrektsen, Sigurd Mørkved; Johansen, Tor Arne (Chapter, 2019)
      Unmanned aerial vehicles (UAVs) often depend on global navigation satellite systems (GNSS) and magnetic compasses for navigation, making them exposed to malicious attacks and sensitive to magnetic anomalies, while restricting ...
    • High Angle of Attack Landing of an Unmanned Aerial Vehicle 

      Gryte, Kristoffer (Master thesis, 2015)
      Motivated by the limited landing space on board a ship, this thesis investigates the landing of the Skywalker X8 fixed wing unmanned aerial vehicle (UAV) in a net. Further motivated by the way birds abruptly, and equally ...
    • Impact of Atmospheric Icing on UAV Aerodynamic Performance 

      Hann, Richard; Wenz, Andreas Wolfgang; Gryte, Kristoffer; Johansen, Tor Arne (Chapter; Conference object, 2017)
      This paper presents a first assessment on the impact of atmospheric icing on the aerodynamic performance of fixed-wing UAVs. Numerical simulations were performed in order to evaluate the impact on lift and drag on a 2D ...
    • LPV model reference control for fixed-wing UAVs 

      Rotondo, Damiano; Cristofaro, Andrea; Gryte, Kristoffer; Johansen, Tor Arne (Journal article; Peer reviewed, 2017)
      This paper proposes a linear parameter varying (LPV) model reference-based control for fixed-wing unmanned aerial vehicles (UAVs), which achieves agile and high performance tracking objectives in extended flight envelopes, ...
    • Precision control of fixed-wing UAV and robust navigation in GNSSdenied environments 

      Gryte, Kristoffer (Doctoral theses at NTNU;2020:198, Doctoral thesis, 2020)
      Unmanned aerial vehicles (UAVs) have been adopted to a wide range of applications, but fully autonomous flight is still utopian, especially for safety-critical applications. This thesis seeks to close this gap by mainly ...
    • Propulsion System Modeling for Small Fixed Wing UAVs 

      Coates, Erlend Magnus Lervik; Wenz, Andreas Wolfgang; Gryte, Kristoffer; Johansen, Tor Arne (Chapter, 2019)
      This paper presents a model of an electrical propulsion system typically used for small fixed wing unmanned aerial vehicles (UAVs). Such systems consist of a power source, an electronic speed controller and a brushless DC ...
    • Robust Navigation of UAV using Inertial Sensors Aided by UWB and RTK GPS 

      Gryte, Kristoffer; Hansen, Jakob Mahler; Johansen, Tor Arne; Fossen, Thor I. (Chapter; Conference object, 2017)
      Tight integration of ultra wideband (UWB) range measurements with real-time kinematic (RTK) aiding of inertial navigation for increased robustness to GNSS dropouts, is achieved using a double-differenced nonlinear observer. ...
    • UAV net landing system for marine operations 

      Bjørsvik, Bård Rørlien (Master thesis, 2017)
      This thesis presents an automatic landing system designed for a fixed-wing unmanned aerial vehicle (UAV) to land in a net placed on ta ship. The UAV used is a Skywalker X8, a cheap and durable airframe, with a Pixhawk as ...
    • Unmanned Aircraft Flight Control Aided by Phased-Array Radio Navigation 

      Gryte, Kristoffer; Bryne, Torleiv Håland; Johansen, Tor Arne (Peer reviewed; Journal article, 2020)
      Navigation systems of safety‐critical unmanned aircraft need an alternative position aiding source to global navigation satellite system. One promising alternative, is position measurements from phased‐array radio systems. ...