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Search results for: HYDRAULIC ACTUATOR POSITION
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Multi Parameter Sliding Test Result Evaluation for the Selection of Material Pair for Wear Resistant Components of a Hydraulic Motor Dedicated for Use with Environmentally Friendly Working Fluids
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Multi parameter sliding test result evaluation for the selection of material pair for wear resistant components of a hydraulic motor dedicated for use with environmentally friendly working fluids
PublicationW referacie przedstawiono zastosowanie metody badań tribologicznych pozwalającej na dokonywanie doboru najlepszych skojarzeń tribologicznych z wybranej populacji poprzez parametryczną ocenę wyników z wielu rodzajów testów tribologicznych wykonywanych na identycznych skojarzeniach materiał - smar - materiał.
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Lubricant property and rolling contact fatigue test of oil-in-water emulsion type HFA-E and oil Total Azolla 46 as working liquids in hydraulic systems
PublicationW artykule scharakteryzowano i opisano wyniki badań własności smarnych wody destylowanej, emulsji wodno-olejowej typu HFA-E (1% oleju w wodzie) sporządzonej na bazie koncentratu Isosynth VX110BF, oleju Total Azolla 46 i samego koncentratu Isosynth VX110BF (tylko dla porównania z olejem, emulsją i wodą). W artykule pokazano wyniki badań pittingu z użyciem wody, emulsji i oleju jako środków smarnych. Ponadto w artykule przedstawiono...
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Reaction of 4-benzylidene-2-methyl-5-oxazolone with amines, Part 2: Influence of substituents in para-position in the phenyl ring and a substituent on amine nitrogen atom on the reaction kinetics
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Graphical presentation of the power of energy losses and power developed in the elements of hydrostatic drive and control system. Part I. Rotational hydraulic motor speed series throttling control systems
PublicationZaproponowano i uzasadniono wykres przedstawiający kierunek wzrostu strumienia mocy narastającej od wału lub tłoczyska silnika hydraulicznego do wału pomopy, mocy narastającej w wyniku wymuszania przez moce strat energetycznych występujących w elementach układu i sterowania hydrostatycznego. Przedstawiono interpretację graficzną mocy strat energetycznych występujących w elementach układów, a także mocy rozwijanych przez te elementy....
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Human Gb3/CD77 synthase reveals specificity toward two or four different acceptors depending on amino acid at position 211, creating Pk, P1 and NOR blood group antigens
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Distance between the Basic Group of the Amino Acid Residue's Side Chain in Position P1of Trypsin Inhibitor CMTI-III and Asp189in the Substrate Pocket of Trypsin Has an Essential Influence on the Inhibitory Activity
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Graphical presentation of the power of energy losses and power developed in the elements hydrostatic drive and control system. Part II. Rotational hydraulic motor speed parallel throtling control and volumetric control systems
PublicationPrzedstawiono interpretację graficzną mocy strat energetycznych występujących w elementach układów napędu i sterowania hydrostatycznego, a także mocy rozwijanych przez te elementy. Dokonano analizy układu indywidualnego ze sterowaniem dławieniowym równoległym prędkości silnika hydraulicznego obrotowego, układu indywidualnego ze sterowaniem objętościowym, pompą o zmiennej wydajności, prędkości silnika hydrailicznego obrotowego,...
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Koncepcja i analiza sensora/aktuatora piezoelektrycznego do pomiaru procesu starzenia się ludzkiej skóry
PublicationNiniejszy artykuł przedstawia nową koncepcję piezoelektrycznego sensora/aktuatora przeznaczonego do pomiaru właściwości mechanicznych tkanek miękkich a w szczególności skóry ludzkiej. Wyjaśnione jest analityczne podejście z wykorzystaniem schematu zastępczego Mason’a określającego aktuator w stanie rezonansu oraz opis metody impedancji elektromechanicznej wykorzystanej w systemie pomiarowym. Analiza z użyciem metody elementów...
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New concept and analysis of the multicell piezoelectric motor
PublicationThis work presents the design, modeling and tests of the prototype multicell piezoelectric motor (MPM). A new concept of the electromechanical structure of the considered prototype is based on three rotating-mode actuators. The electromechanical structure of each actuator has been considered as an independent one - referred to as a ”single cell” (single actuator). Combined three resonant actuators generate three traveling waves...
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Chosen Analysis Results Of The Prototype Multicell Piezoelectric Motor
PublicationThis paper presents the design, modeling and tests of the prototype multicell piezoelectric motor (MPM). A new concept of the electromechanical structure of the considered prototype is based on three rotating-mode actuators. The electromechanical structure of each actuator has been considered as an independent one - referred to as a “single cell” (single actuator). Combined three resonant actuators generate three traveling waves...
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Adaptive dynamic control allocation for over-actuated dynamic positioning system based on backstepping method in case of thruster faults
PublicationThe objective of the research considered in this paper is dynamic positioning of a nonlinear over-actuated marine vessel in the presence of limited information about thruster forces. First, the adaptive backstepping method is used to estimate the input matrix which will compensate partial loss of actuator effectiveness in the presence of actuator dynamics. Then, the adaptive commanded virtual forces and moment are allocated into...
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Robust identification of quadrocopter model for control purposes
PublicationThe paper addresses a problem of quadrotor unmanned aerial vehicle (so-called X4-flyer or quadrocopter) utility model identification for control design purposes. To that goal the quadrotor model is assumed to be composed of two abstracted subsystems, namely a rigid body (plant) and four motors equipped with blades (actuators). The model of the former is acquired based on a well-established dynamic equations of motion while the...
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Fuzzy Control of Waves Generation in a Towing Tank
PublicationThis paper presents the results of research related to the transformation of electrical energy into potential and kinetic energy of waves generated on the water surface. The waves are generated to model the environmental conditions for the needs of the model tests. The model tests are performed on model-scale objects to predict the features of full-scale maritime objects. It is done to improve human safety and the survivability...
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Utilization of a Non-Linear Error Function in a Positioning Algorithm for Distance Measurement Systems Designed for Indoor Environments
PublicationA new positioning algorithm for distance measurement systems is outlined herein. This algorithm utilizes a non-linear error function which allows us to improve the positioning accuracy in highly difficult indoor environments. The non-linear error function also allows us to adjust the performance of the algorithm to the particular environmental conditions. The well-known positioning algorithms have limitations, mentioned by their...
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Developments in unsteady pipe flow friction modelling
PublicationW pracy omówiono wpływ błędów numerycznych na jakość rozwiązania równań uderzenia hydraulicznego. Wykazano rolę dyfuzji numerycznej i jej wpływ na dokładność rozwiązania w porównaniu z członem tarcia.
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Volumetric and torque efficiency of pumps during start-up in low ambient temperatures
PublicationThe volumetric, torque and total efficiency of hydraulic pumps change during start-up in low ambient temperatures, as well as in thermal shock conditions, un-til they reach the set conditions. The time to reach steady-state conditions de-pends on many parameters: ambient temperature, flow rate, fluid temperature, design of hydraulic units. The author carried out tests of hydraulic pumps in the Hydraulics Laboratory of the Faculty...
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Wpływ strat mechanicznych w siłowniku teleskopowym zespołu zagęszczającego w pojeździe do usuwania odpadów z pojemników na skuteczność prasowania odpadów
PublicationHydraulic telescopic cylinders are used to power the moving wall of rear loader garbage trucks equipped with the traditional "sweep and slide" system. As the garbage compression force is directly dependent on the resistance force of the moving wall, losses in the hydraulic telescopic cylinder influence the compaction process. Taking them into account in the control system may improve the operation of the compaction...
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Problem of Clogging in Drainage Systems in the Examples of the Zur and Podgaje Dams
PublicationDrainage plays an extremely important role in hydraulic structures, such as earth dams. Observations of drainage in hydraulic structures under various soil conditions indicate that the phenomenon of clogging can lead to a radical reduction in the efficiency of drainage, making it non-functional within a few years after construction. This article describes the problems of drainage clogging by iron oxide in the examples of the Zur...
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Research of hydrotronic variable displacement radial piston pump with electro -pneumatic control
PublicationThe paper presents the developed new electro-pneumatic control (pneumotronic) system for hydraulic fixed-displacement radial piston pump. Hydraulic fixed-displacement radial piston pump equipped with the proposed control system changes into hydrotronic variable-displacement radial piston pump. Pump flow rate control is realized by means of programmable logic controller, electro-pneumatic valves, pneumatic cylinders and a sensor.
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The Methodology for Determining the Theoretical Based on the Characteristics of Effective Absorbency Versus Pressure Drop in the Motor
PublicationThis article describes a method for determining the theoretical and actual working volume of a hydraulic motor. It has been shown that the actual working volume of the motor is the sum of the theoretical working volume and the additional volume that depends on the pressure drop in the working chambers of the motor. It was also shown that the volumetric losses in the hydraulic motor are not only a function of the pressure drop in...
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New Design of Axial Piston Pump with Displaced Swash Plate Axis of Rotation for Hydro-Mechanical Transmissions
PublicationThis paper presents a prototype design of an axial piston pump with displaced swash plate axis of rotation in two directions of discharge with electronic control intended for installation on a hydraulic-mechanical gearbox dedicated to working machines. The effect of displacement of the swash plate rotation axis on dead space volume and volumetric efficiency is presented. The construction and principle of operation of the capacity...
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Shallow Water Equations as a Mathematical Model of Whitewater Course Hydrodynamics
PublicationPredicting the positions of local hydraulic phenomena, as well as accurately esti-mating the depth and velocity of the water flow are necessary to correctly config-ure a whitewater canoeing course. Currently, a laboratory and full 3D CFD model-ing are typically used in the design process to meet these needs. The article points to another possibility which can be useful at the preliminary stage of the design. The authors show that...
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Porównanie własności smarnych wody, emulsji oleju w wodzie typu HFA-E oraz oleju Total Azolla 46 jako czynników roboczych w układach hydraulicznych = Comparison of the lubricant property of water oil-in-water emulsion type HFA-E and oil total Azolla 46 as working liquids in hydraulic systems
PublicationW artykule scharakteryzowano i opisano wyniki badań własności smarnych wody destylowanej, 1% emulsji oleju w wodzie typu HFA-E sporządzonej na bazie koncentratu do tworzenia emulsji Isosynth VH110BF, oleju Total Azolla 46 oraz, w celach porównawczych, samego koncentratu Isosynth VH110BF. Przedstawiono również wyniki badań powierzchniowego zużycia zmęczeniowego (pittingu), dla wyżej wymienionych czynników smarnych. Emulsja oleju...
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Perforating systems in shale gas recovery
PublicationHydraulic fracturing is common method of shale gas recovery. Due to environmental, economical and technological problems many alternative technologies have been developed. One of the most promising group of technologies is based on perforating systems. This paper describes theoretical and practical aspects of best known technologies used to create perforations. New perforating/fracturing technologies which can replace hydraulic fracturing...
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NEW CONCEPT OF HYBRID PROPULSION WITH HYDROSTATIC GEAR FOR INLAND WATER TRANSPORT
PublicationThe article presents the development of author’s concept of a diesel/hydraulic propulsion system for inland watercraft. Due to specific nature of vessel navigation on rivers, classical propulsion systems with shaft lines can be effectively replaced by systems with hydraulic power transmission. A solution is also presented of a hybrid design with extra electric port having the form of a pumping system driven from a battery of accumulators....
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Methodology of experimental research on efficiency of hydro-mechanical automatic gearbox
PublicationThe article shortly describes the design and principle of operation of the hydromechanical gearbox and presents the methodology and design of test stands used for testing hydromechanical proto-type gearbox developed at Technical University of Gdansk. The article presents an approach according to which, in order to obtain reliable measurement data, it is necessary to separate the tests of the hydraulic and mechanical parts of the...
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Trailing-Edge Separation Control of a NACA 0015 Airfoil Using Dielectric-Barrier-Discharge Plasma Actuators
PublicationThis paper presents a part of the works conducted in the Plasmaero European project (task 3.1), where the trailing-edge flow separation of a NACA 0015 airfoil has been controlled using four different dielectric barrier discharge (DBD) actuator types at three institutions across Europe. The results show that it is possible to enhance the aerodynamic performance of aircraft at speeds up to 40 m/s. Dielectric-barrier-discharge vortex...
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Discussion of “Development of an Accurate Time integration Technique for the Assessment of Q-Based versus h-Based Formulations of the Diffusion Wave Equation for Flow Routing” by K. Hasanvand, M.R. Hashemi and M.J. Abedini
PublicationThe discusser read the original with great interest. It seems, however, that some aspects of the original paper need additional comments. The authors of the original paper discuss the accuracy of a numerical solution of the diffusion wave equation formulated with respect to different state variables. The analysis focuses on nonlinear equations in the form of a single transport equation with the discharge Q (volumetric flow rate)...
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Wave damping and smoothing in the unsteady pipe flow
Publicationlaboratoryjne eksperymenty wykonane dla rur polietylenowych o różnej długości wykazały obecność takich zjawisk jak zmienna prędkość propagującej fali ciśnienia oraz jej intensywne tłumienie i wygładzanie. w artykule zaproponowano modyfikacje standardowych równań przepływu nieustalonego. polega ona na wprowadzeniu zmiennej prędkości fali oraz dyssypacji energii na jej czole opisanej członem dyfuzyjnym. do rozwiązania równań zaproponowano...
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Experimental Study of the Influence of Small Upward Seepage on Open-Channel Flow Turbulence
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Reservoir Influence on Pressure Wave Propagation in Steel Pipes
PublicationThe relation between the length of steel pipe and the pressure wave period in the system, reservoir-pipe-valve, is discussed. Experiments carried out for the short steel pipes showed that in such a system, the pressure wave celerity estimated using the measured wave cycles systematically increases with the increase of the pipe length. The observed differences can exceed even 90 m=s. As the pressure wave traveling in the pipe with...
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Residence time distribution in rapid multiphase reactors
PublicationResidence time distribution (RTD) provides information about average hydraulic residence time and the distribution of material in the reactor. A method for determining RTD for reactors with very short hydraulic residence times is deconvolution based on extraction of real RTD by the analysis of a non-ideal input signal. The mean residence time and dispersion were determined for the spinning fluids reactor (SFR). For the first time...
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Localization of sound sources with dual acoustic vector sensor
PublicationThe aim of the work is to estimate the position of sound sources. The proposed method uses a setup of two acoustic vector sensors (AVS). The intersection of azimuth rays from each AVS should indicate the position of a source. In practice, the result of position estimation using this method is an area rather than a point. This is a result of inaccuracy of the individual sensors, but more importantly, of the influence of a source...
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Design, modelling and analysis of a new type of piezoelectric motor. Multicell piezoelectric motor
PublicationThis paper describes a new type of piezoelectric motor. The results, obtained in the field of piezoelectric motors, have pointed out that these motors have potentially high possibilities in the future special applications. The research work presents the design, simulations and parameters of the piezoelectric motor with three rotation-mode actuators. The motor is characterized by a high power, relative high speed and torque. The...
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Elastic wave propagation for condition assessment of steel bar embedded in mortar
PublicationThis study deals with experimental and numerical investigations of elastic wave propagation in steel bars partially embedded in mortar. The bars with different bonding lengths were tested. Two types of damage were considered: damage of the steel bar and damage of the mortar. Longitudinal waves were excited by a piezoelectric actuator and a vibrometer was used to non-contact measurements of velocity signals. Numerical calculations...
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Application of wavelet transform in analysis of guided wave propagation signals for damage detection in a steel plate
PublicationThe paper presents results of experimental investigations on damage detection using guided wave propagation technique. The tested specimen was a steel plate with a defect in the form of a rectangular notch. Lamb waves were excited by a PZT actuator and sensed by a laser vibrometer. Since reflections from damage in registered signals are often masked by measurement noise, for identification of time of reflections from damage, continuous...
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Safety of erection and repair of steel tanks with geometric imperfections using heavylift jack-up system
PublicationSafety analysis is performed of cylindrical vertical steel tanks during erection using heavylift jack up system. During an assembly or repair process a set of hydraulic supports is used. It allows to use the in-place lifting of heavy steel constructions on the required height. Wind can strongly influence stability of the lifted tank. Any geometric imperfections can reduce the critical or limit load. In the work failures of the...
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Influence of the particle size of carbonate-siliceous rock on the efficiency of phosphorous removal from domestic wastewater
PublicationtThe aim of the study was to determine the influence of the particle size of carbonate–silica rock (opoka)used in rock filters on the efficiency of phosphorus removal from domestic wastewater. The investigationswere carried out in a laboratory using a model consisting of three vertical flow filters with carbonate–silicarock of different particle sizes (G1= 1–2 mm; G2= 2–5 mm; G3= 5–10 mm). The tested rock was subjectedto decarbonising...
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Design and modeling of the piezoelectric motor based on three resonance actuators
PublicationThis paper describes a piezoelectric motor which combines advantages from two existing piezoelectric motors topologies. The research work presents the design, simulations and measurements of the piezoelectric motor with three rotation-mode actuators. The aim of the project was to obtain the high speed piezoelectric motor. Other advantages of this conception are blocking torque, short response times, the ability to work in a hostile...
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Evaluation of the efficiency of the duty cycle of refuse collection vehicle based on real-world data
PublicationIn this paper a method of the efficiency evaluation of the duty cycle of Refuse Collection Vehicle is presented. Using real world data, two representative duty cycles were analysed. Total cycle efficiency was calculated, as well as the efficiency of particular cycle phases. Then, energy needed to collect and compact the waste and energy from fuel were compared. Measured and calculated values were shown on the diagrams illustrating...
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Window frame integrable air recuperation minichannel/minigap heat exchanger
PublicationThis article describes an evaluation of mini heat exchangers operation as a decentralized mechanical ventilation system with recuperative heat recovery that can be integrated into the window frame. The relatively small yet efficient air recuperation system allows for retrofitting existing buildings by reducing the overall energy consumption and thus the CO2 emissions. The proposed design, unlike existing systems, is easy to scale...
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Comparative Analysis of Exoskeletal Actuators
PublicationSince the beginning of the development of exoskeletons in the early 1960s there was a constant need for improving their actuators technology. Requirements for high power and torque for the lower body and very high precision for the hand motion, while maintaining the flexibility of biological muscles, are still not fully satisfied. The problem lies not just in the lack of appropriate actuator technology, but also in the inability...
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Numerical investigation on the performance of a small counter-rotating wind turbine
PublicationThe article presents the results of the investigation on the performance of a small counter-rotating wind turbine. The wind turbine has been simulated using Computational Fluid Dynamics methods. Actuator Line Model has been successfully used to represent rotors in the computational domain. A parametric study has been carried out, taking into account changes in the tip speed ratio of the rotors while maintaining a constant distance...
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Wave propagation in damage assessment of ground anchors
PublicationThe inspection possibilities of ground anchors are limited to destructive test such as pull-out test. Guided wave propagation gives an opportunity to develop an inspection system dedicated to determine the condition of inspected element without violation of their integrity. In this paper the experimental study on wave propagation in laboratory models of ground anchors are presented. Experiments were conducted for different bonding...
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The influence of the geographic positioning system error on the quality of ship magnetic signature reproduction based on measurements in sea conditions
PublicationIn previous studies, the authors performed the magnetic signature reconstruction of the marine ship Zodiak as part of the measurement campaign focused on recording magnetic data and the relative position of a ship during its passage over a magnetometer immersed on the testing ground. A high degree of representation of the magnetic signature was obtained. However, the recorded measurement data revealed new patterns of the multidipole model...
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Non-Least Square GNSS Positioning Algorithm for Densely Urbanized Areas
PublicationThe paper introduces an essentially new algorithm for calculating the GNSS position as an alternative to the least-square method. The proposed approach can be widely applied to any positioning method that uses multiple position lines for position calculation and is an example ofhow using a numerical solution can improve position accuracy without access to historical data. In essence, the method is based on the adaptation of the...
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Control design for slow speed positioning
PublicationThe problem under study is a synthesis of position and heading control system for low frequency model of surface vessel described by 3 DOF mathematical model. The recursive vectorial backstepping control design was used to keep fixed position and heading in presence of wave disturbances. The controller has been simulated on computer model of scaled supply vessel. It has been assumed that the actuators produce generalized forces...
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Performance of DS-CDMA Radionavigation Receiver with Subsample Time Measurement Resolution in Various Environments
PublicationThis paper presents results of investigation of position estimation performance in TDOA radionavigation system with receiver containing code tracking loop with subsample time measurement resolution. Position estimation accuracy was evaluated using real signals from CDMA base stations, recorded during measurement campaigns in various environments: on sea, flat terrain and hilly terrain.
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The Positioning Accuracy of BAUV Using Fusion of Data from USBL System and Movement Parameters Measurements
PublicationThe article presents a study of the accuracy of estimating the position coordinates of BAUV (Biomimetic Autonomous Underwater Vehicle) by the extended Kalman filter (EKF) method. The fusion of movement parameters measurements and position coordinates fixes was applied. The movement parameters measurements are carried out by on-board navigation devices, while the position coordinates fixes are done by the USBL (Ultra Short Base...