Formation of a reference model for the method of inverse dynamics in the tasks of control of underwater complexes

2017

EEJET

Self Cite

Section: Fundamentals Of the Methods For Scaling Errors In Maintainingmentioning

confidence: 99%

“…In this regard, we shall apply decomposition of the reference model in accordance with [22]. This will allow us to invert a mathematical model of ROV by its components, as well as apply a matrix form of the basic law of ROV dynamics.…”

Section: Synthesis Of Automated Control System For the Rov Spatialmentioning

confidence: 99%

Devising a method for maintaining manageability at multidimensional automated control of tethered underwater vehicle

2017

EEJET

Self Cite

“…The inverse dynamics method implements the concept of inverse control and with the complete initial information provides highly precise control of complex nonlinear objects including UCFT [21]. Let us apply it for synthesis of the FT model regulator.…”

Section: Synthesis Of the Flexible Tether Model Regulator Using The Imentioning

confidence: 99%

Development of the mathematical modeling method for dynamics of the flexible tether as an element of the underwater complex

2017

EEJET

Self Cite

a result, these equations are strongly coupled, which has to be taken into account when simulating UCFTs. Due to equations nonlinearity usually it is impossible to find an analytical solution of such a complicated problem, hence numerical methods are employed.The motion of MMOs as of solid bodies in the water flow has been well studied [2,3]. The MMO mathematical models include mathematical models of their hulls, hydrodynamic drags, propulsive complexes, bearing surfaces, and other elements. As a rule, it is possible to develop an MMO mathematical model in the form of ordinary differential equations system, despite complex dependencies between parameters of model elements. This allows applying effective methods of numerical solution of differential equations to the MMO simulation.The flexible tether modeling is a more challenging problem, as the FT is an object with distributed parameters which is described by a system of nonlinear differential equations with partial derivatives. Two approaches were evolved for modeling FT dynamics [4]. These are segmental and lumped-mass-spring (LMS) methods. For the former the FT is modeled as a continuous system and resulting partial differential equations are solved numerically by finite difference or any suitable approximation method. In the LMS approach the cable is modeled as mass points joined together by massless elastic elements of finite length, which makes it possible to express the FT model in the form of ordinary differential equations. All the forces along the cable are assumed to be concentrated at the mass points. IntroductionUnderwater complexes with flexible tethers (UCFT) consist of two types of elements: those with lumped and distributed parameters. The former include marine mobile objects (MMO): surface vessels, submarines, remotely operated vehicles (ROV) and others. The latter include flexible tethers (FT): umbilical cables, towing cables, anchor chains, etc. An example of a two-linked UCFT is shown in Fig. 1 [1]. Fig. 1. Two-linked underwater complex with flexible tethersMathematical modeling is one of the main methods of the UCFT studies. In this regard, the UCFT motion simulators should include corresponding MMO and FT mathematical models. It is known that their motion equations are non-linear and their dynamic behaviors are mutually dependent. As APPLIED MECHANICS DEVELOPMENT OF THE MATHEMATICAL MODELING METHOD FOR DYNAMICS OF THE FLEXIBLE TETHER AS AN ELEMENT OF THE UNDERWATER COMPLEX О . B l i n t s o vPhD, Assistant Professor Department of Information Security Lviv Polytechnic National University S. Bandery str., 12, Lviv, Ukraine, 79000 E-mail: energybox@mail.ruРозроблено метод математичного моделю-вання динаміки гнучкого зв'язку (ГЗ) на основі автоматичного контролю осьового руху його еле-ментів. Синтезовано регулятор відстаней між елементами ГЗ як складова математичної моде-лі. Запропоновано спосіб моделювання ГЗ зі змін-ною довжиною. Показано ефективність розробле-ного методу у порівнянні з методом зосереджених мас та еластичних зв'язків при мо...

“…The method of inverse dynamics (ID) makes it possible to synthesize high-accuracy ACSs for complex nonlinear objects, including UCFTs [29]. Development of inverse models for UCFT elements, which parts can be specified including graphical or tabular form, is a prerequisite for its use.…”

Section: Determination Of Development Directions Of the Automatic mentioning

confidence: 99%

Tasks Statement for Modern Automatic Control Theory of Underwater Complexes With Flexible Tethers

Dudykevych

EUREKA: Physics and Engineering

2016

The definition of a new class of control objects is proposed. It is an underwater complex with flexible tethers (UCFT) for which there is the need to automate motion control under uncertainty and nonstationarity of own parameters and external disturbances. Classification of marine mobile objects and characteristics of the flexible tethers as UCFT elements is given. The basic UCFTs configurations that are used in the implementation of advanced underwater technologies are revealed. They include single-, double- and three-linked structures with surface or underwater support vessels and self-propelled or towed underwater vehicles. The role of mathematical modeling in tasks of motion control automation is shown. The tasks of UCFT mathematical modeling are formulated for synthesis and study of its automatic control systems. Generalized structures of mathematical models of UCFT basic elements are proposed as the basis for the creation of simulating complex to study the dynamics of its motion. The tasks of UCFT identification as a control object are formulated. Their consistent solution will help to obtain a UCFT mathematical model. The basic requirements for UCFT automatic motion control systems are determined. Their satisfaction will ensure implementation of selected underwater technology. Areas of development of synthesis methods of UCFT automatic control systems are highlighted.