• A control framework for biologically inspired underwater swimming manipulators equipped with thrusters 

      Sverdrup-Thygeson, Jørgen; Kelasidi, Eleni; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (IFAC Proceedings series;, Journal article; Peer reviewed, 2016)
      In this paper we present a control framework for a novel biologically inspired underwater swimming manipulator (USM) equipped with thrusters. The framework consists of a kinematic part and a dynamic part. The kinematic ...
    • A control-oriented model of underwater snake robots exposed to currents 

      Kohl, Anna M.; Kelasidi, Eleni; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (Conference object; Journal article; Peer reviewed, 2015)
      This paper presents a control-oriented model of a neutrally buoyant underwater snake robot that is exposed to a constant irrotational current. The robot is assumed to move in a horizontal, fully submerged plane with a ...
    • A Control–Oriented Model of Underwater Snake Robots 

      Kelasidi, Eleni; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (Conference Publications;ROBIO 2014, Conference object; Journal article; Peer reviewed, 2014)
      In this paper we consider swimming underwater snake robots that are fully immersed in water and moving in a virtual horizontal plane. The main objective of the paper is to develop a model that is well suited for control ...
    • A waypoint guidance strategy for underwater snake robots 

      Kelasidi, Eleni; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (Journal article; Peer reviewed, 2014)
      In this paper, a waypoint guidance strategy is proposed for an underwater snake robot. The robot is directed to follow a path which is derived using path planning techniques. A first version of the path is derived by ...
    • An Experimental Investigation of Path Following for an Underwater Snake Robot with a Caudal Fin 

      Kelasidi, Eleni; Pettersen, Kristin Ytterstad; Kohl, Anna M; Gravdahl, Jan Tommy (Journal article; Peer reviewed, 2017)
      In this paper, we present a bioinspired underwater snake robot (USR) equipped with a passive caudal (tail) fin. In particular, a highly flexible configuration of a USR is presented, which is capable of locomotion both on ...
    • Analysis of underwater snake robot locomotion based on a control-oriented model 

      Kohl, Anna M.; Pettersen, Kristin Ytterstad; Kelasidi, Eleni; Gravdahl, Jan Tommy (Proceedings of the 2015 IEEE Conference on Robotics and Biomimetics;, Journal article; Conference object; Peer reviewed, 2015)
      This paper presents an analysis of planar underwater snake robot locomotion in the presence of ocean currents. The robot is assumed to be neutrally buoyant and move fully submerged with a planar sinusoidal gait and limited ...
    • Control of an Underwater Swimming Manipulator, With Compensation for Reaction Forces and Hydrostatic Forces 

      Amundsen, Morten Fyhn (Master thesis, 2017)
      The underwater swimming manipulator (USM) is a new class of robots that combines the underwater snake robot's biologically inspired shape with the thruster actuators typical of other underwater robots. This combination ...
    • Energy efficiency of underwater robots 

      Kelasidi, Eleni; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (Conference object; Journal article; Peer reviewed, 2015)
      Increasing efficiency by improving locomotion methods is a key issue for underwater robots. In this paper, we investigate the power consumption of different underwater robotic systems and compare the energy efficiency of ...
    • Energy efficiency of underwater snake robot locomotion 

      Kelasidi, Eleni; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (Journal article; Peer reviewed, 2015)
      Energy efficiency is one of the main challenges for long-term autonomy of underwater robotic systems. In this paper, we present results regarding the power consumption of underwater snake robots. In particular, we investigate ...
    • Experimental investigation of efficient locomotion of underwater snake robots for lateral undulation and eel-like motion patterns 

      Kelasidi, Eleni; Liljebäck, Pål; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (Journal article, 2015)
      Underwater snake robots offer many interesting capabilities for underwater operations. The long and slender structure of such robots provide superior capabilities for access through narrow openings and within confined ...
    • 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 ...
    • Fluid Parameter Identification for Underwater Snake Robots 

      Kelasidi, Eleni; Elgenes, G; Kilvær, H (Journal article; Peer reviewed, 2018)
      Nowadays different types of unmanned underwater vehicles (UUVs), such as remotely operated vehicles (ROVs) and autonomous underwater vehicles (AUVs), are widely used for subsea inspection, maintenance, and repair (IMR) ...
    • 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 ...
    • Innovation in Underwater Robots: Biologically Inspired Swimming Snake Robots 

      Kelasidi, Eleni; Liljebäck, Pål; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (Journal article; Peer reviewed, 2016)
      Increasing efficiency by improving locomotion methods is a key issue for underwater robots. Moreover, a number of different control design challenges must be solved to realize operational swimming robots for underwater ...
    • Integral Line-of-Sight for path following of underwater snake robots 

      Kelasidi, Eleni; Pettersen, Kristin Ytterstad; Liljebäck, Pål; Gravdahl, Jan Tommy (Conference object; Journal article; Peer reviewed, 2014)
      This paper considers straight line path following control of underwater snake robots in the presence of constant irrotational currents. An integral line-of-sight (LOS) guidance law is proposed, which is combined with a ...
    • Integral Line-of-Sight Guidance for Path Following Control of Underwater Snake Robots: Theory and Experiments 

      Kelasidi, Eleni; Liljebäck, Pål; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (Journal article; Peer reviewed, 2017)
      This paper proposes and experimentally validates a straight line path following controller for underwater snake robots in the presence of constant irrotational currents of unknown direction and magnitude. An integral ...
    • Inverse Kinematic Control of a Free-Floating Underwater Manipulator Using the Generalized Jacobian Matrix 

      Amundsen, Morten Fyhn; Sverdrup-Thygeson, Jørgen; Kelasidi, Eleni; Pettersen, Kristin Ytterstad (Chapter, 2018)
      Traditional control of robot manipulators assume that the base of the manipulator is fixed in the environment. However, underwater vehicle-manipulator systems are usually floating freely. Using traditional fixed-base ...
    • Learning an AUV docking maneuver with a convolutional neural network 

      Sans-Muntadas, Albert; Kelasidi, Eleni; Pettersen, Kristin Ytterstad; Brekke, Edmund Førland (Chapter, 2017)
      This paper proposes and implements a convolutional neural network (CNN) that maps images from a camera to an error signal to guide and control an autonomous underwater vehicle into the entrance of a docking station. The ...
    • Locomotion Efficiency of Underwater Snake Robots with Thrusters 

      Kelasidi, Eleni; Pettersen, Kristin Ytterstad; Liljebäck, Pål; Gravdahl, Jan Tommy (Chapter; Conference object; Peer reviewed, 2016)
      Lately there has been an increasing interest for subsea inspection and intervention tasks, and in particular on solutions which combine smaller size, increased flexibility and maneuverability, and decreased cost. Biologically ...
    • Locomotion efficiency optimization of biologically inspired snake robots 

      Kelasidi, Eleni; Jesmani, Mansoureh; Pettersen, Kristin Ytterstad; Gravdahl, Jan Tommy (Journal article; Peer reviewed, 2018)
      Snake robots constitute bio-inspired solutions that have been studied due to their ability to move in challenging environments where other types of robots, such as wheeled or legged robots, usually fail. In this paper, we ...