Steady three dimensional gliding motion of an underwater glider

Abstract

Abstract-Underwater Gliders have found broad applications in ocean sampling. In this paper, the nonlinear dynamic model of the glider developed by the Shenyang Institute of Automation, Chinese Academy of Sciences, is established. Based on this model, we solve for the parameters that characterize steady state spiraling motions of the glider. A set of nonlinear equations are simplified so that a recursive algorithm can be used to find the solutions. , and the straight line gliding motion in the vertical plane are stabilized by feedback control. The complex dynamic model and the coupled hydrodynamic effects make it difficult to find accurate solutions for the glider model that establishes relationships between the gliding state and the control input. The problem remains unsolved for three dimensional gliding motion such as the spiraling motion. In [9], a first attempt is made to find numerical solutions for the steady state equations that characterize the spiraling motion. In [12] and [13], an approximate analytical solution for steady spiraling motion is derived by applying perturbation theory. I. INTRODUCTIONThe dynamic performance of an underwater glider is strongly affected by hydrodynamics. In [14], a thorough analysis about the hydrodynamic coefficients of a glider is performed. In [15], the drag and lift forces caused by wings of a fin-actuated underwater vehicle are studied. In [16], the hydrodynamic coefficients of autonomous underwater vehicles are verified using the computational fluid dynamics method and experiments. The effect of independently controllable wings on a glider is studied to enhance the glider maneuverability in [17].The underwater glider developed by the Shenyang Institute of Automation (SIA) in [18] is propelled by a pump and steered by a movable-rotatable battery. The heave is controlled by the pump that changes the volume of a bladder.

Tail-Enabled Spiraling Maneuver for Gliding Robotic Fish

“…The typical operation of underwater gliders is rectilinear, zigzag gliding in a vertical plane, while the nominal operation of robotic fish is fin-flapping-enabled swimming. There are also a few studies about the three-dimensional (3D) spiral gliding of underwater gliders, which is predominantly realized by translating or rotating an internal mass [19][20][21][22][23][24]. In this paper, we investigate a novel form of gliding where a deflected tail induces 3D spiraling motion [25], which enables energy-efficient maneuvering without constant actuation of the tail.…”

“…The dynamics of underwater gliders have been studied mostly for movable mass and net buoyancy-controlled gliding in the literature [19][20][21][22][23][24]27,28]. In this paper, we focus on the influence of a deflected tail and study the resulting 3D spiraling motion.…”

An Artificial Neural Network Based Power Control strategy of Low-Speed Induction Machine Flywheel Energy Storage System

“…There are two types of bearing, conventional mechanical bearings and magnetic bearings, and the usage of each depends mainly on the desired operating speed and the cost. In case of low speed flywheels, conventional bearings can be used while in case of high speed flywheels, magnetic bearings should be used to reduce friction and losses but their cost is much higher than conventional bearings [16]. Controlling the power flow between the FESS and the grid is the main concern of this paper.…”