Now showing items 101-120 of 308

    • Experimental investigation of locomotion efficiency and path-following for underwater snake robots with and without a caudal fin 

      Kelasidi, Eleni; Kohl, Anna M; Pettersen, Kristin Ytterstad; Hoffmann, B; Gravdahl, Jan Tommy (Journal article; Peer reviewed, 2018)
      Over the last few decades, the robotics community has shown increasing interest in developing bioinspired swimming robots, driven by the need for more economical, more efficient, autonomous, highly flexible and maneuverable ...
    • Experimental Investigation of Obstacle-Aided Locomotion With a Snake Robot 

      Liljeback, Pål; Pettersen, Kristin Ytterstad; Stavdahl, Øyvind; Gravdahl, Jan Tommy (Journal article; Peer reviewed, 2011)
      In a recent paper, the authors have proposed a control strategy for a snake robot during obstacle-aided locomotion. In this paper, experimental results are presented where the controller is shown to successfully maintain ...
    • Experimental Testing, Dynamic Modeling and Control of Roll and Pitch for a SES with a Split Cushion 

      Haukeland, Ola Mosebø (Master thesis, 2019)
      Denne masteroppgaven undersøker egenskapene for rull og trim demping til et overflateffektskip med en luftpute som er delt inn i fire separate putekamre. Denne nye puteinndelingen gjør det mulig å generere et motvirkende ...
    • Exponential Convergence Bounds in Least Squares Estimation: Identification of Viscoelastic Properties in Atomic Force Microscopy 

      Ragazzon, Michael Remo Palmén; Gravdahl, Jan Tommy; Pettersen, Kristin Ytterstad (Journal article; Peer reviewed, 2017)
      Using atomic force microscopy (AFM) for studying soft, biological material has become increasingly popular in recent years. New approaches allow the use of recursive least squares estimation to identify the viscoelastic ...
    • Feedback linearizing neural network controllers 

      Sterud, Camilla (Master thesis, 2019)
      Når reguleringssystemer anvendes i praksis er ukjent og umodellert dynamikk et tilbakevendende problem. Ved anvendelse av avanserte reguleringstekniske metoder, som modellbasert prediktiv og tilbakekoblingslineariserende ...
    • Fixed-Structure, Low-Order Damping and Tracking Control Schemes for Nanopositioning 

      Eielsen, Arnfinn Aas; Vagia, Marialena; Gravdahl, Jan Tommy; Pettersen, Kristin Ytterstad (Journal article; Peer reviewed, 2013)
      Fast and accurate tracking of periodic reference trajectories is highly desirable in many nanopositioning applications, including scanning probe microscopy. Performance in common positioning stage designs is limited by the ...
    • Formation Control of Underactuated Bio-inspired Snake Robots 

      Rezapour, Ehsan; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy; Hofmann, Andreas (Journal article; Peer reviewed, 2016)
      This paper considers formation control of snake robots. In particular, based on a simplified locomotion model, and using the method of virtual holonomic constraints, we control the body shape of the robot to a desired gait ...
    • Fractional-order Control: Nyquist Constrained Optimization 

      Moltumyr, Andreas Hanssen; Ragazzon, Michael Remo Palmén; Gravdahl, Jan Tommy (Peer reviewed; Journal article, 2020)
      The adoption of fractional calculus in control systems has enabled the synthesis of new controllers with fractional-order derivatives and integrals. Several optimization-based methods for tuning of linear fractional-order ...
    • Fundamental properties of snake robot locomotion 

      Liljeback, Pål; Pettersen, Kristin Ytterstad; Stavdahl, Øyvind; Gravdahl, Jan Tommy (Chapter, 2010)
      This paper presents a set of fundamental properties of the velocity of a snake robot conducting lateral undulation on a planar surface. In particular, the derived properties state that the average forward velocity of the ...
    • Generalized Lyapunov Demodulator for Amplitude and Phase Estimation by the Internal Model Principle 

      Ragazzon, Michael Remo Palmén; Messineo, Saverio; Gravdahl, Jan Tommy; Harcombe, David M.; Ruppert, Michael G. (Journal article; Peer reviewed, 2019)
      Effective demodulation of amplitude and phase is a requirement in a wide array of applications. Recent efforts have increased the demodulation performance, in particular, the Lyapunov demodulator allows bandwidths up to ...
    • The Generalized Lyapunov Demodulator: High-Bandwidth, Low-Noise Amplitude and Phase Estimation 

      Ragazzon, Michael Remo Palmén; Messineo, Saverio; Gravdahl, Jan Tommy; Harcombe, David M.; Ruppert, Michael G. (Journal article, 2022)
      Effective demodulation of amplitude and phase is a requirement in a wide array of applications. Recent efforts have increased the demodulation performance, in particular, the Lyapunov demodulator allows bandwidths up to ...
    • The generalized super-twisting algorithm with adaptive gains 

      Borlaug, Ida-Louise Garmann; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (Chapter, 2020)
      In this paper a novel adaptive generalized super-twisting algorithm is proposed for a class of systems whose perturbations and uncertain control coefficients are time- and state-dependent. The proposed approach uses ...
    • The generalized super-twisting algorithm with adaptive gains 

      Borlaug, Ida-Louise Garmann; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (Peer reviewed; Journal article, 2022)
      In this article, a novel adaptive generalized super-twisting algorithm (GSTA) is proposed for a class of systems whose perturbations and uncertain control coefficients may depend on both time and state. The proposed approach ...
    • Guidance and Control of Underwater Snake Robots Using Planar Sinusoidal Gaits 

      Kohl, Anna M. (Doctoral theses at NTNU;2017:292, Doctoral thesis, 2017)
      This thesis presents different approaches for guidance and motion control of underwater snake robots. The robots considered in this thesis are neutrally buoyant and move slowly with a planar, biologically inspired sinusoidal ...
    • H_inf Reduced Order Control for Nanopositioning: Numerical Implementability 

      Ragazzon, Michael Remo Palmén; Eielsen, Arnfinn Aas; Gravdahl, Jan Tommy (IFAC Proceedings series;, Journal article; Peer reviewed, 2014)
      In this paper we discuss how model reduction affects the stability and computational complexity of controllers for nanopositioning systems. A robust H∞ multiple-input multiple-output controller is designed and implemented ...
    • Heave Motion Estimation on a Craft Using a Strapdown Inertial Measurement Unit 

      Auestad, Øyvind Fidje; Gravdahl, Jan Tommy; Fossen, Thor I. (Journal article; Peer reviewed, 2013)
      This paper deals with heave position and heave velocity estimation on a craft. The estimation is done without any knowledge of the specified craft. An accurate estimation of these signals is useful when one wants to control ...
    • Hierarchical Compliance-Control-Based Docking of a UVMS 

      Nysæther, Torje; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (Journal article, 2023)
      The viability of underwater vehicle-manipulator systems (UVMS) in underwater intervention missions is heavily reliant on safety. For safe operations, a UVMS should specifically be able to both avoid dangers and interact ...
    • Hierarchical tracking control of an articulated intervention-AUV 

      Dyrhaug, Jan Inge; Tveter, Erling (Master thesis, 2022)
      Autonome undervannsroboter har allerede revolusjonert den maritime næringen, og muliggjort operasjoner som ellers ville vært umulige. Økt autonomi er ønskelig av flere grunner, inkludert kostnadseffektivitet og sikkerhet. ...
    • Hierarchical tracking control of an articulated intervention-AUV 

      Dyrhaug, Jan Inge; Tveter, Erling (Master thesis, 2022)
      Autonome undervannsroboter har allerede revolusjonert den maritime næringen, og muliggjort operasjoner som ellers ville vært umulige. Økt autonomi er ønskelig av flere grunner, inkludert kostnadseffektivitet og sikkerhet. ...