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EN
For many years, satellite systems have seen widespread use in a variety of technical applications, as well as in operations related to setting-out and the exploitation of track infrastructure. Their main applications include an inventory of the trackage course and detecting changes in its position. In both of these tasks, the most important element that determines the quality of an analyses is the high accuracy of the determinations being carried out. Satellite surveying techniques are not always sufficiently accurate, and in such cases, it is necessary to employ other land surveying methods to process surveying data. This article presents the authors’ considerations with regards to the possibility of applying one of the most common land surveying adjustment methods, the parametric method, to operations related to an inventory of tram infrastructure in Gdańsk. The results are based on surveys carried out during a surveying campaign in the autumn of 2018. The considerations presented in the article concern a small part of the research conducted under project No. POIR.04.01.01-00-0017/17 entitled “Development of an innovative method for determining the precise trajectory of a railborne vehicle” which is being implemented by a consortium of Gdansk University of Technology and Gdynia Maritime University
EN
The goal of this paper is to investigate the influence of the objectively existing effectiveness functions of an aircraft control system upon the control and managerial decision making process in the framework of the subjective entropy maximum principle. The subjective analysis theory entropy paradigm makes it possible to consider the aircraft control system based upon personal preferences as an active system governed by an individual (active element of the control system) with the help of her/his individual subjective preferences optimal distributions obtained in conditions of operational multi-alternativeness and those operational alternatives the active system active element’s individual subjective preferences uncertainty. The described approach takes into account the simple two-alternative operational situation in regards with the objectively existing effectiveness functions, related to the aircraft control system, in the view of a controlled parameter and a combination of it with its rate as the ratio. The obtained expressions for the objective functional extremal functions of the effectiveness and preferences, as well as the subjective entropy of the alternatives preferences, illustrated in diagrams visualize the situation and allow taking a good choice. The ideas of the required proper governing, managing, and control methods choice optimization with respect to only 2 alternative objective effectiveness functions arguments might be simple; nevertheless, increasing the number of parameters and further complication of the problem setting will not change the principle of the problem solution.
PL
Celem tej publikacji jest zbadanie wpływu obiektywnie istniejących funkcji skuteczności systemu kontroli statku powietrznego na proces kontroli i podejmowania decyzji zarządczych w ramach subiektywnej zasady maksymalnej entropii. Paradygmat entropii teorii subiektywnej umożliwia rozważenie systemu sterowania samolotem opartego na osobistych preferencjach jako systemu aktywnego zarządzanego przez jednostkę (aktywny element systemu sterowania) za pomocą jej indywidualnych preferencji subiektywnych, optymalnych rozkładów uzyskanych w warunkach operacyjnej multi-alternatywności i operacyjnych alternatyw niepewności subiektywnych indywidualnych preferencji elementu aktywnego systemu. Opisane podejście uwzględnia proste dwie alternatywne sytuacje operacyjne w odniesieniu do obiektywnie istniejących funkcji efektywności związanych z systemem sterowania statkiem powietrznym w świetle kontrolowanego parametru i jego kombinacji Uzyskane wyrażenia dla obiektywnych funkcjonalnych ekstremalnych funkcji skuteczności i preferencji, a także subiektywna entropia preferencji alternatyw, zilustrowane na schematach, pokazują sytuację i pozwalają na dokonanie dobrego wyboru. Pomysły dotyczące wymaganej właściwej optymalizacji metod zarządzania i kontroli w odniesieniu do tylko dwóch alternatywnych argumentów funkcji efektywności celu mogą być proste – niemniej jednak zwiększenie liczby parametrów i dalsze komplikowanie problemu nie zmieni zasady rozwiązania.
EN
The paper presents the analysis of navigation processes used in wells and around-drilling processes. Most common navigation systems used in drilling processes are described. The authors have presented a concept of applying navigation to operations supporting drilling processes, including operations ensuring the safety of drilling staff. Also, they have discussed around-drilling processes which have not been supported by navigation systems. Finally, they have presented ideas of their possible applications as well as benefits resulting from using navigation systems.
EN
The article describes the methodology related to determining the multi-criteria routes for sailing ships. Details of sea area discretisation and discretisation of the description of the sailing vessel properties and manoeuvring principles are shown. User requirements were specified (for five different categories of users) and on this basis the criteria for selecting the most suitable shipping route were formulated. The presented algorithm recommends a route for a given user category by means of defined restrictions and configuration parameters. The applied multi-criteria approach proves the universality and usability of the sailing ship route planning method.
EN
The paper presents a multi-objective method, which optimises the route of a sailboat. The presented method makes use of an evolutionary multi-objective (EMO) algorithm, which performs the optimisation according to three objective functions: total passage time, a sum of all course alterations made during the voyage and the average angle of heel. The last two of the objective functions reflect the navigator’s and passenger’s comfort, which may decrease with multiple turns or when experiencing an excessive heel angle for a long time. The optimisation process takes into account static bathymetry-related constraints as well as dynamic constraints related to the sailboat’s safety in changing wind and wave conditions. The method makes use of all of the above and finally returns an approximated Pareto set containing non-dominated solutions to the optimisation problem. The developed method has been implemented as a simulation application. The paper includes selected simulation results followed by their discussion.
EN
The article compares the accuracy of receivers related to the geolocation process in the GPS system. To determine the accuracy of the receivers, a series of research experiments were conducted based on test cases. For the needs of the research, a research platform for collecting data from the GPS system was designed and constructed. The research results are presented in the form of tables and graphic charts.
PL
W artykule porównano dokładność odbiorników związanych z procesem geolokalizacji w systemie GPS. W celu okre-ślenia dokładności odbiorników przeprowadzono serię eksperymentów badawczych w oparciu o przypadki testowe. Na potrzeby badań została zaprojektowana oraz skonstruowana platforma badawcza służąca do gromadzenia danych z systemu GPS. Rezultaty badań przedstawiono w postaci tabel oraz wykresów graficznych.
7
Content available Start Acceleration of the Space GPS Receiver
EN
The cold start of the space GPS receiver, i.e. the start without any information about the receiver position, satellite constellation, and time, is complicated by a large Doppler shift of a navigation signal caused by the satellite movement on the Earth orbit. That increases about five times the search space of the navigation signals compared to the standard GPS receiver. The paper investigates a method of the acceleration of the GPS receiver cold start time designed for the pico- and femto-satellites. The proposed method is based on a combination of the paralel search in Doppler frequency and PRN codes and the serial search in code phase delay. It can shorten the cold start time of the GPS receiver operating on LEO orbit from about 300 to 60 seconds while keeping the simplicity of FPGA signal processor and low power consumption. The developed algorithm was successfully implemented and tested in the piNAV GPS receiver. The Energy required for the obtaining of the position fix was reduced five times from 36 on to 7.7 Joules. This improvement enables applications of such receiver for the position determination in smaller satellites like Pocket Cube or femto-satellites with a lower energy budget than the Cube Satellite.
EN
Contingent planning models a robot that must achieve a goal in a partially observable environment with non-deterministic actions. A solution for this problem is generated by searching in the space of belief states, where a belief state is a set of possible world states. However, if there is an unavoidable dead-end state, the robot will fail to accomplish his task. In this work, rather than limiting a contingent planning task to the agent's actions and observations, we model a planning agent that is able to proactively resort to humans for help in order to complete tasks that would be unsolvable otherwise. Our aim is to develop a symbiotic autonomous agent, that is, an agent that, proactively and autonomously, asks for human help when needed. We formalize this problem and propose an extension of a translation technique to convert the contingent planning problem with human help into a non-deterministic fully observable planning problem that can be solved by an off-the-shelf efficient FOND planner.
9
Content available Radar data fusion in the STRADAR system
EN
The main task of the Polish Border Guard is protection of the country’s border which requires utilization of multimedia surveillance systems automatically gathering, processing and sharing various data. The paper presents such a system developed for the Maritime Division of the Polish Border Guard within the STRADAR project and the problem of fusion of radar data in this system. The system, apart from providing communication means, gathers data from AIS, GPS and radar receivers: ARPA and SCANTER 2001. In the paper the concept of the radar data gathering in STRADAR system is provided with detailed presentation of radar servers, Radar INT modules and a reduplication (fusion) module and the proposition of the algorithm for radar data fusio.
PL
Głównym zadaniem polskiej Straży Granicznej jest ochrona granicy kraju, która wymaga wykorzystania multimedialnych systemów nadzoru umożliwiającychautomatyczne gromadzenie,przetwarzanie i udostępnianie różnego rodzaju danych. W artykule przedstawiono taki system opracowany dla Morskiego Oddziału Straży Granicznej w ramach projektu STRADAR oraz problem fuzji danych radarowych w tym systemie. System STRADAR, oprócz zapewnienia komunikacji pomiędzy elementami systemu, gromadzi i udostępniania dane z AIS, GPS i odbiorników radarowych: ARPA i SCANTER 2001. W artykule zaprezentowano koncepcjęgromadzenia danych adarowych w systemie STRADAR, przedstawiono serwery radarowe, moduł radar INT i moduł reduplikacjioraz zaproponowano algorytm fuzji danych radarowych.
EN
The article proposes the possibilities of testing military equipment using satellite navigation systems, as well as systems that aid such systems, used for determining the position of and indicating targets. The research employed modern civilian navigation devices using satellite navigation systems, as well as navigation aided by land-based reference stations. Using Trimble R8 and RT4000 devices in research is proposed. The possibilities of the RT4000 precise movement parameter measuring device within the scope of position determining using a portable reference station using the Trimble R4 receiver and Satel-TA18 radio (not the device’s standard equipment) are presented.
PL
W artykule zaproponowano możliwości prowadzenia badań sprzętu wojskowego, w których wykorzystuje się systemy nawigacji satelitarnej oraz systemy wspomagające systemy nawigacji satelitarnej służące do określania pozycji oraz wskazywania celów. W baniach wykorzystano cywilne nowoczesne urządzenia nawigacyjne korzystające z systemów nawigacji satelitarnej oraz nawigacji wspomaganej referencyjnymi stacjami naziemnymi. Zaproponowano możliwości zastosowania urządzeń Trimble R8 i RT4000 w badaniach sprzętu wojskowego. Przedstawiono możliwość urządzenia do precyzyjnych pomiarów parametrów ruchu RT4000 w zakresie dokładności określania pozycji przy zastosowaniu przenośnej stacji referencyjnej wykorzystującej odbiornik Trimble R4 i radio Satel-TA18, które nie są standardowym wyposażaniem RT4000.
11
Content available Main aspects of a maritime e-navigation project
EN
Many devices and systems, including electronic ones, are used in the operation of sea-going vessels. Fast technological development in the field of electronics, radio communications and computer science inspires the more and more new proposals for the changes of these devices and systems. The rules and scope of sea-going vessels equipment, related to ensuring their safety, are strictly regulated by the International Maritime Organization (IMO). Considering the above, several countries have submitted to the IMO-Maritime Safety Committee (MSC) a proposal to prepare a vision of a broad strategy for incorporating new technologies in a structural manner, ensuring their compatibility with already existing different navigation and communication technologies and services. The overriding goal of this strategy would be to improve the efficiency, safety and reducing the cost of the entire system, providing global coverage and applicable to all types of sea-going vessels. In response to this proposal, the MSC decided to start work on the project "Preparation of e-navigation strategy". The article presents the general concepts and goals of the e-navigation project. Priority needs of e-navigation users were also discussed. The key elements of the project are presented too. The radio communication aspects of the e-navigation project were also considered. Finally, the enavigation Strategy Implementation Plan (SIP) and its progress were presented.
PL
Przedstawiono informacje o działaniach wodnych prowadzonych w Królestwie Polskim w latach 1843-1859. Informacje oparte są na sprawozdaniach przedstawicieli rządu składanych do Rady Administracyjnej Królestwa. Informacją objęto działania dla uspławnienia rzek (oczyszczanie i poszerzanie rzek), obwałowania Wisły i innych rzek oraz prace związane z utrzymaniem Kanału Augustowskiego.
EN
The article presents water initiatives carried out in the Kingdom of Poland in the years 1843-1859. The presented information is based on reports submitted by the government representatives to the Kingdom's Administrative Council. It includes initiatives aimed at making rivers more navigable (cleaning and widening), construction of flood embankments Vistula and other rivers and maintenance works on the Augustów Canal.
13
Content available Wykorzystanie UAV w nawigacji
PL
Na przestrzeni ostatnich lat nastąpił bardzo dynamiczny rozwój bezzałogowych jednostek, które są wykorzystywane niemal w każdej dziedzinie życia. W artykule przedstawiono możliwości wykorzystania UAV w szeroko pojętej nawigacji, jak możemy korzystać z dronów w środowisku morskim, obserwować porty, prowadzić misje na morzu, jak robić mapy dna morskiego i jakie korzyści z dronów ma środowisko wojskowe.
EN
Over the past years, there has been a very dynamic development of unmanned aerial vehicles that are used in almost every area of life. The article presents the possibilities of using UAVs in the broadly understood navigation, how to use drones in the sea environment, observe ports, conduct missions at sea, how to make seabed maps and how drones are used in the army.
14
PL
Poruszony problem wyznaczenia lokalizacji obiektu logistycznego z zastosowaniem metody wielkiego koła rozpatrywany jest podczas konfigurowania sieci logistycznej w celu minimalizacji kosztów logistycznych oraz optymalizacji poziomu obsługi klienta. W artykule przedstawiono trzy metody obliczania odległości między dwoma punktami, czyli metodę wyznaczania odległości na krótkich dystansach bez uwzględniania krzywizny Ziemi, metodę związaną z loksodromą i wyznaczaniem odległości na średnich dystansach z uwzględnieniem krzywizny Ziemi, a także metodę wielkiego koła i ortodromy służącą do wyznaczania odległości na długich dystansach z uwzględnieniem krzywizny Ziemi. Na podstawie uzyskanych wyników, w których analizowano także poziom skomplikowania obliczeń, stwierdzono, że metoda wielkiego koła, czyli związana z ortodromą charakteryzuje się możliwością zastosowania we wszystkich przypadkach zarówno krótkich, średnich i długich odległości, a jej dokładność jest porównywalna z metodami preferowanymi dla danych dystansów.
EN
The goal of the article is to present three methods for determining the location of a logistic facility with minimum logistic costs and optimum level of customer service. In the first method, path over short distances is calculated, without taking into account the curvature of the Earth. The second method, in which a loxodrome and the curvature of the Earth are taken into account, is used to determine the route on medium distances. The third method, used to determine route over long distances combines the formula of the great circle path with an orthodrome, with the curvature of the Earth taken into account. On the basis of the results obtained with each method, it was found that the great circle method associated with orthodrome may be applied for any distance, offering accuracy comparable with the methods preferred for given distances. The complexity of calculations when either the great circle method or the loxodrome are applied is definitely higher than when the method for short distances is used.
EN
The article is strongly related to the Single European Sky ATM Research (SESAR) project. The project’s objective is the improvement of air transport above Europe 0. Since Air Traffic Management (ATM) is involved to obtain more effective approach to air traffic flow managing activities, the concept of Flexible Use Airspace (FUA) has arisen in result. ATM is a quite developed aviation’s subdomain, therefore currently existing airspace state has been described briefly in the article, referring to the presented solution concept. The notion of Free Route Airspace (FRA) airspace model defined in this article relies on mathematical description. The selected approach clarifies airspace as a set of squares or cubes that have volumes with appointed values due to certain conditions in the considered time (i.e. traffic flow or weather). The model has to ensure facilitation of flight route planning and warrant aircrafts separation towards flight safety assurance. The concept assumes that this airspace model will provide assistance for airspace user to select essential flight plan criteria, such as economy, time, etc. The path will be appointed according to personal preferences, based on the model from which further elaborated algorithm will evaluate situation. The presented solution is a response to air traffic growth. Therefore it supports the SESAR project through research and development activities. The description proves that airspace model would create enhancement in flight planning for airspace users.
PL
Artykuł przedstawia koncepcję zamodelowanej przestrzeni powietrznej w sposób umożliwiający automatyczne planowanie lotu w Przestrzeni Lotów Swobodnych (Free Route Airspace – FRA). Zaprezentowany model usprawnia czynności składania planu lotu przez użytkownika, jednocześnie gwarantując bezpieczną separację statków powietrznych. Tematyka artykułu jest związana z badaniami do projektu Jednolitej Europejskiej Przestrzeni Powietrznej (Single European ATM Research – SESAR), której podstawowe założenie stanowi poprawa efektywności i bezpieczeństwa operacji w transporcie lotniczym. Efektywniejsze Zarządzanie Ruchem Lotniczym (Air Traffic Management – ATM) jest możliwe przez wprowadzenie koncepcji Elastycznego Zarządzania Przestrzenią Powietrzną (Flexible Use of Airspace – FUA). Elastyczne Zarządzanie Przestrzenią Powietrzną pozwala na monitorowanie dostępności przestrzeni w różnych odstępach czasowych, w sposób umożliwiający uwzględnienie planowanego natężenia ruchu wobec innych warunków, np. atmosferycznych. Przedstawiony w artykule opis przestrzeni powietrznej opiera się na opisie matematycznym. Przyjęte zostało założenie, że cała przestrzeń powietrzna składa się z jednakowej wielkości kwadratów (lub sześcianów w przypadku przestrzeni 3D). Każdy kwadrat lub sześcian ma przydzieloną pojemność wraz z wartościami określającymi dostępność w ustalonym czasie. Dostępność jest uwarunkowana przez wiele czynników, np. zagęszczenie ruchu lotniczego. Wykonane badania wskazują, że zamodelowana w ten sposób przestrzeń powietrzna stwarza potencjał do planowania lotu. W konsekwencji wprowadzenia przez użytkownika dwóch punktów lotu – początkowego i końcowego, przeszukana w następstwie przestrzeń pozwala na przeanalizowanie i zaproponowanie przez system trasy według przyjętego kryterium.
EN
Port approaches are high-traffic areas with limited manoeuvring space. Navigation in such areas requires the analysis of large amounts of information, which can impede decision processes. One solution may be the development of decision support systems dedicated to these areas. This paper presents an attempt to build a navigation decision support system operable in the approach area leading to the port of Świnoujście (Poland), with ship domain implemented as a safety criterion. Assumptions for a decision support system to be used by sea-going vessels in port approach areas are formulated and discussed. Specific features of these areas, such as traffic density, bathymetry, available manoeuvring space and legal limitations are taken into account. The source and scope of information available to the ship have been analysed. The scope of decision support has been defined. A ship domain has been proposed as a safety criterion. Approach areas leading to the port of Świnoujście have been investigated on the basis of real Automatic Identification System (AIS) data. Vessel movement processes in the chosen area were analysed. Ship domains in various parts of the area were determined. The first results concerning criteria for navigational safety assessment are presented. The conducted studies showed significant differences in the size of domains. A case study was performed on a decision support system operable in the approach area leading to Świnoujście.
PL
W artykule zaprezentowano miniaturowego robota mobilnego MiniRyś. Robot ma napęd różnicowy i z założenia może poruszać się w dwóch trybach: poziomym, gdzie zderzak stanowi trzeci punkt podparcia i pionowym, balansując. Robot, pomimo małych rozmiarów wymuszonych przez operowanie w środowisku składającym się z kwadratowych pól o boku 20 cm, wyposażony jest w rozbudowany zestaw czujników i wydajny komputer pozwalające na samodzielne nawigowanie i komunikację w ramach zespołu robotów.
EN
In the article a MiniRyś (a "mini lynx") miniature mobile robot is presented. The robot is differentially driven and can move in two modes: horizontally, where a bumper is the third point of support for the robot and vertically, balancing using a built-in inertial measurement unit. Although the robot is small (it was constructed to operate on a board built out of 20cm x 20cm square tiles) it is equipped with a broad set of sensors and a computer with relatively high computation power allowing the robot to navigate autonomously and communicate within a team of such robots.
EN
The main source of information on the situation across the sea basins used by operators of shipping monitoring systems is a network of coastal radar stations. Presently, it is possible to gather navigational information from many individual radar stations simultaneously, which may be used for improving the accuracy of vessel position fixing. However, without making other estimates, we obtain an inconsistent image comprising multiple echoes of the same ship, and as such it is impossible to say which echo presents the vessel on the move. Another problem is the method of performing radar observations, which significantly affects the accuracy of position fixing. The estimated radar distance is encumbered with a gross error in the case of large vessels, as the position of a large vessel is not the same as the position of the edge of the radar echo to which the estimation is made. In this paper, the authors present a method to adjust the measured radar distance. The proposed method may be automated easily, which would significantly enhance VTS positioning processes.
EN
The article presents a method to determine the route of a sailing vessel with the aid of deterministic algorithms. The method assumes that the area in which the route is to be determined is limited and the basic input data comprise the wind vector and the speed characteristic of the vessel. Compared to previous works of the authors, the present article additionally takes into account the effect of sea waves with the resultant resistance increase on the vessel speed. This approach brings the proposed model closer to real behaviour of a sailing vessel. The result returned by the method is the sailing route, optimised based on the multi-criteria objective function. Along with the time criterion, this function also takes into account comfort of voyage and the number of performed turns. The developed method has been implemented as simulation application SaillingAssistance and experimentally verified.
EN
This paper presents a comparative study of Robot Operating System (ROS) packages for mobile robot navigation on an embedded system. ROS provides various libraries and tools in developing complex robot software. We discuss the process of porting ROS to an open embedded platform, which serves as the main controller for a mobile robot. In the case of driving the robot, ROS provides local path planners such as the base, elastic band, and timed elastic band. The local planners are compared and analyzed in terms of accuracy in tracking the global path conducted on a robot model using Gazebo, 3D simulation tool provided by ROS. We also discussed the difference in performance of deploying ROS packages on a personal computer and on the embedded environment. Experiments were performed by controlling two different mobile robots with results showing that tracking error is highly dependent on the goal tolerance. This study will serve as a promising metric in improving the performance of mobile robots using ROS navigation packages.
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