Navigation Data Processing Research Articles

The task of determining the actual routes in the traffic control system using satellite navigation

The paper deals with the task of determining the actual traffic routes based on the data of the global satellite navigation system during the dispatching control of road transport. The actual route through the transport network is an ordered set of traffic control points passed. The fixation of control points of the route in the processing of satellite navigation data is carried out by means of two radii: the radius of detection and the radius of positioning. The paper proposes a method for processing satellite navigation data, consisting of two stages: first, pre-processing and, second, calculating the parameters of the system states defined by the dispatch control tasks. The state of the system controlled by the traffic dispatcher system is described.

CONSTRUCTION OF A NEUROET NETWORK EXPERT SYSTEM FOR PROCESSING NAVIGATION DATA IN CONDITIONS RIVER е-NAVIGATION

Context. The diagnostics automatisation problem of network anomalies during navigation data processing from gauging stations to electronic chart system under river e-navigation was studied. The object of the study is a process of diagnostic in the dynamic expert system. The purpose of the research is creating of automated troubleshooting system with a help of neural system.Method. The diagnostic automatisation method of network anomalies with context-based intelligent navigation data processing usage was suggested. The main idea consists in modern data processing methods usage in the neural system. These methods are based on the fuzzy logic algorithm. Neural networks can be in operation during parameter fluctuations, that come from gauging stations. The cluster-rules set is displayed in the fuzzy neural system structure. There is no need to download all sample specifications in the electronic mapping system or to re-check the sample, it helps to speed up the process of network synthesis. Inthe navigation data processing system were used different expert systems and neural networks. Data processing system should find network anomalies and propose the ways of their decision size, the method allows to get different levels of sample specification. The method allows to minimize network error in the synthesized model. In addition to fractal method, also had been proposed a method for unknown regularities between the input and output data coming from the gauging stations. That is, the neural network can determine which signals are non-informative. With a help of input data classification from the gauging stations based on Kokhonen`s system, the space of the data stream splits into clusters of the same size and shape. By changing the cluster size, the method allows toget different levels of sample specification. The procedure of input signals classification helps to predict the increasing or decreasing of differential corrections towards depth, and recognize information from gauging stations. The method determines the encoding and decoding of navigation parameters by specifying the parametric function of the triangular shape. The rules formed by an expertknowledge were established. In order to keep intellectual system under current conditions should be used neural dynamic expert system model including use case. The mechanism of automated solution based on the search use case algorithm is defined. If there are not any use cases, the task solves with a help of neural network rules. The network nodes are neurons – particular facts that areconsequences of use case. Links between nodes of the network implement the rules. That is, a multilayer neural network of facts and rules is built up.Results. The experimental indexes of network anomalies during data processing from the gauging stations were followed up.Conclusions. The automatisation problem of network diagnostic anomalies with a help of flexible fuzzy neural network was solved. The conducted experiments confirmed the efficiency of the proposed methods. Further research may consist in the creation of an instrumental navigation method (river e-navigation).

Solving the Nonlinear Problems of Estimation for Navigation Data Processing Using Continuous-Time Particle Filter

A new continuous-time particle filter algorithm is proposed for solving the problems of nonlinear estimation of signal when describing the mathematical models of an observed object and a measuring system by means of stochastic differential equations. This algorithm can be used in the estimation problems related to navigation data processing. The algorithm verification is presented by example of a navigation system error estimation using geophysical field map data.

Решение нелинейных задач оценивания при обработке навигационных данных с использованием непрерывного фильтра частиц

Решение нелинейных задач оценивания при обработке навигационных данных с использованием непрерывного фильтра частиц

EVALUATION OF TRANSPORT FLOW EFFICIENCY ON THE BASIS OF TRAFFIC MOVEMENT DATA

The paper considers a method for evaluation of transport flow parameters and determine an efficiency of variants concerning organization of traffic movement and provision of qualitative transportation. A method for evaluation of main traffic flow parameters while using a two-fluid mathematical model of Herman – Prigogine has been developed and it is based on passive processing of navigation data for road transport facilities on highways and urban road and street networks. The main advantages and novelty of the method (in contrast with the traditional usage of a mathematical model of Her- man – Prigogine on the basis of active processing of navigation data) are the following: a passive treatment of GPS-tracks and support of their formats that make it possible significantly improve quality and adequacy of the model results; cloud com-puting (usage of cloud storage for storing large bulk of data); presence of client mobile application for Android operating system which is used for data collection in addition to operation with already collected navigation data from navigation and information center and other sources; application for calculation and processing of modern web technologies; scalability and configurability of the system. Efficiency of the proposed algorithms, mathematical models for evaluation of transport flow parameters and system as a whole have been proved in the process of their approbation while using a set of tracks on main highways of Belarus

Problem-Oriented Approach to Identification of Sensor Error Models and its Application to Navigation Data Processing

The paper proposes a problem-oriented approach to identification of error models of navigation sensors based on the solution of a joint hypotheses recognition and parameter estimation problem. The examples illustrating the proposed approach demonstrate that the obtained algorithms outperform the existing ones.

A model of function-level fault tolerance of navigation signals provision processes in adverse conditions

The aim of this article is to develop a model that would allow quantitatively evaluating the function-level fault tolerance of navigation signals provision processes in adverse reception conditions using consumer navigation equipment (CNE). The article also substantiates the relevance and importance of evaluation of the function-level fault tolerance of consumer navigation systems in those cases when the reception of the signals is affected by industrial interference, pseudo-satellites, rereflections from urban structures and terrain features. The function-level fault tolerance of the processes of navigation signals (of CNE) provision to consumers in adverse conditions is understood as their ability to fulfil their functions and retain the allowed parameter values under information technology interference within a given time period. The adverse conditions of provision of navigation data (signals) to consumers are understood as a set of undesirable events and statuses of reception and processing of navigation data with possible distortions. The article analyzes a standard certificate of vulnerabilities of navigation signal (by the example of distortion of pseudorange and pseudovelocity values distortion) that defines the input data for the analysis of CNE equipment fault tolerance. The model is based on the following approaches: the navigation signal parameters are pseudorange and pseudovelocity, system almanac data and ephemeris information; quantitative evaluation of function-level fault tolerance of the processes of navigation signals provision to users is based on the probability of no-failure of CNE in adverse conditions; function-level fault tolerance of the above processes is ensured by means of integrated use of functional, hardware, software and time redundancy; the hardware and software structure of the CNE fault tolerance facilities has the form of a three-element hot and cold standby system; the allowable level of functionlevel fault tolerance violation risk is defined according to the ALARP principle. It is shown that CNE fault tolerance and jamming resistance is based on the following: use of multisystem navigation receivers; navigation signal integrity supervision; spatial and frequency-time selection of signal; precorrelation processing of signal and interference mixture; postcorrelation signal processing; processing of radio-frequency and information parameters of the signal; cryptographic authentication; integration with external sources of navigation information and within a single signal processing system of a number of methods of interference countermeasures and pseudo-satellite navigation signals. The proposed model defines the CNE function-level fault tolerance as two variants of dynamic dependability models, in which the values of probability of no-failure are time-dependent: a hot standby system that includes three additional countermeasure modules and a cold standby system with a switch to three additional countermeasures modules. The model allows visualizing the processes of navigation signals provision to users in adverse conditions, quantitatively evaluating the probability of no-failure for hot and cold standby systems with three modules of information technology interference countermeasures, probability of recovery and CNE availability coefficient, as well as the allowable risk of CNE fault tolerance violation.

STRUCTURAL SYNTHESIS OF NAVIGATION SUPPORT OF TRIAD INTEGRATED NAVIGATION SYSTEM ON THE BASIS OF INERTIAL AND SATELLITE TECHNOLOGIES

In connection with the increasing complexity of aircraft navigation support, with growing demands placed on them, it is increasingly necessary to develop integrated navigation data processing system by solving synthesis problems based on optimal filtering methods. One of the promising ways to improve aircraft navigation support is to create an integrated navigation system (INS). In this work the triadic structure of a promising integrated navigation system based on inertial and satellite technologies is proposed. Combining nautical meters as part of the triad concept allows the flexible use of various navigation data processing algorithms and trajectory optimization ones at different stages of flight. Based on optimal filtering theory methods the integrated navigation data processing algorithm, which is an extended Kalman filter, is synthesized. A distinctive feature of the algorithm is that the variables of the state vector which are to be measured, are the errors in the determination of appropriate navigation and timing parameters. Priori information about the dynamics of errors is more reliably known than the one about aircraft motion variables. It is shown that the use of the proposed navigation system as a navigation aid for problem solving of highly accurate aircraft position indication satisfies the requirements for navigation and timing data accuracy. The imitating statistical modeling of optimal filtering algorithm of the triad integrated system is carried out. The accuracy characteristics of subsystems for different operating configurations of the constellation are given. Analysis of the results of the accuracy characteristics study of INS in various operating conditions has showed that the positioning accuracy in the navigation computer is up to date satellite navigation receivers.

Navigation of differential drive mobile robot on predefined, software designed path

This paper will be presenting the process of mobile robot movement controlling, from the task of collecting sensor data until the problem of controlling data to the servo motor controllers. In details, the first part will show the mechanism of converting CAD data to routes, and the processing of the navigation data read from the sensors and calculated from former controlling commands. The second part will explain the processing of navigation data, the applying of the actual robot position and orientation on the predefined virtual path and the production of the controller's input variables. The Fuzzy controller and the rule base will be introduced in the third part.

Cramér–Rao lower bound in nonlinear filtering problems under noises and measurement errors dependent on estimated parameters

This paper derives recurrent expressions for the maximum attainable estimation accuracy calculated using the Cramer---Rao inequality (Cramer---Rao lower bound) in the discretetime nonlinear filtering problem under conditions when generating noises in the state vector and measurement error equations depend on estimated parameters and the state vector incorporates a constant subvector. We establish a connection to similar expressions in the case of no such dependence. An example illustrates application of the obtained algorithms to lowerbound accuracy calculation in a parameter estimation problem often arising in navigation data processing within a model described by the sum of a Wiener sequence and discrete-time white noise of an unknown variance.

ARCHITECTURE AND ORGANIZATION THE SYSTEM THAT HANDLES THE NAVIGATIONAL INFORMATION OF MICROSATELLITE

The navigation system must provide accurate and rapid determination of microsatellite navigation information, be small-sized and have low power consumption. Navigational information microsatellite's processing system (NIMPS) used to identify microsatellite, recording and processing of navigation data to determine the position of microsatellite relative Earth and the subsequent transfer of this information to carry of microsatellite tasks. In this article, the structure of hardware and software system, and research-based standards for the exchange of information between navigation devices, passport data and electrical circuits of the receiver AN-4706, analyzed the possibility of its application.Conventionally NIMPS can be divided into on-board (devices on board microsatellite) and off-board components (hardware and software that runs on Earth).The main components of NIMPS are receiver radio frequencies (RF – receiver), the navigation processor, RF-antenna and additional elements for the operation: output serial interface for transferring data RS-232 software to display navigation information and more.The practical significance of the proposed presents the printed circuit board that can be used for further experimental studies of microsatellite processing of navigational information.This will ensure small-sized, reducing power consumption, and enable to improve the accuracy of registration and processing of microsatellite navigation information through the use of advanced algorithms for processing and filtering of signals.

Unmanned aerial systems for photogrammetry and remote sensing: A review

We discuss the evolution and state-of-the-art of the use of Unmanned Aerial Systems (UAS) in the field of Photogrammetry and Remote Sensing (PaRS). UAS, Remotely-Piloted Aerial Systems, Unmanned Aerial Vehicles or simply, drones are a hot topic comprising a diverse array of aspects including technology, privacy rights, safety and regulations, and even war and peace. Modern photogrammetry and remote sensing identified the potential of UAS-sourced imagery more than thirty years ago. In the last five years, these two sister disciplines have developed technology and methods that challenge the current aeronautical regulatory framework and their own traditional acquisition and processing methods. Navety and ingenuity have combined off-the-shelf, low-cost equipment with sophisticated computer vision, robotics and geomatic engineering. The results are cm-level resolution and accuracy products that can be generated even with cameras costing a few-hundred euros. In this review article, following a brief historic background and regulatory status analysis, we review the recent unmanned aircraft, sensing, navigation, orientation and general data processing developments for UAS photogrammetry and remote sensing with emphasis on the nano-micro-mini UAS segment.

MODELS AND METHODS FOR AUTOMATION OF DISPATCHING MANAGEMENT FOR RAILWAYS OF UKRAINE

В статье представлена общая схема функционирования подсистемы координации движения подвижных средств, описан принцип решения задачи координации движения подвижных средств на основе взаимодействия разработанных алгоритмов, для каждого из которых приведено краткое описание. Дано формальное представление моделей и методов автоматизации диспетчерского управления.

Performance Analysis of Alignment Process of MEMS IMU

The procedure of determining the initial values of the attitude angles (pitch, roll, and heading) is known as the alignment. Also, it is essential to align an inertial system before the start of navigation. Unless the inertial system is not aligned with the vehicle, the information provided by MEMS (microelectromechanical system) sensors is not useful for navigating the vehicle. At the moment MEMS gyroscopes have poor characteristics and it’s necessary to develop specific algorithms in order to obtain the attitude information of the object. Most of the standard algorithms for the attitude estimation are not suitable when using MEMS inertial sensors. The wavelet technique, the Kalman filter, and the quaternion are not new in navigation data processing. But the joint use of those techniques for MEMS sensor data processing can give some new results. In this paper the performance of a developed algorithm for the attitude estimation using MEMS IMU (inertial measurement unit) is tested. The obtained results are compared with the attitude output of another commercial GPS/IMU device by Xsens. The impact of MEMS sensor measurement noises on an alignment process is analysed. Some recommendations for the Kalman filter algorithm tuning to decrease standard deviation of the attitude estimation are given.

Using frequency approach to time-variant filtering for processing of navigation information

The paper considers a procedure for linear time-variant filtering used in navigation data processing. The proposed procedure is based on studying and simplifying the valid signal and measurement error models in the frequency domain. The application of this procedure to synthesis of autonomous and corrected gyro verticals is illustrated by examples. Comparative analysis of the accuracy in transient state is performed for time-invariant and time-variant filtering.

India’s first lunar mission Chandrayaan-1 initial phase orbit determination

India’s first Moon mission Chandrayaan-1 carrying eleven scientific instruments for the purpose of expanding scientific knowledge about the Moon was launched on 22 October 2008. The spacecraft was put into Moon’s polar, circular orbit of about (100×100) km on 12 November 2008 by carrying out a sequence of Earth bound and Lunar bound maneuvers. Precise orbit determinations are carried out during each phase of the mission using tracking data collected from network of tracking stations configured for the mission. The determined orbital solutions are used for spacecraft navigation, mission planning and science data processing. ISRO’s operational orbit determination program (ODP) used for low earth missions was suitably updated and validated before the launch of Chandrayaan-1. The purpose of this paper is to describe the methodology and the performance of Chandrayaan-1 orbit determination system during initial phase of the mission along with achieved orbit determination accuracy in the early normal phase.

Space Navigation Applications

Over the past 25 years, we have witnessed the extraordinary achievements of both robotic and manned space missions. A key element in the success of these missions has been the development of the navigation systems that have enabled the determination of current and predicted spacecraft position and velocity to the accuracies required to meet mission objectives. This paper presents an overview of space navigation systems, navigation techniques, and capabilities for robotic and manned mission applications for the past 25 years. Robotic navigation system data types, information content, and navigation data processing techniques are reviewed. Application of these systems to planetary missions is discussed, with emphasis placed on the Voyager mission. For manned space navigation systems, the role of on-board and ground navigation capabilities is presented. Key technology developments that enabled the development of on-board systems are discussed. Ground and on-board navigation data types and their information content, data processing techniques, and system operations are reviewed. Application of these ground and on-board systems to Apollo, Skylab, Apollo/Soyuz, the Space Shuttle, and the Space Station is described. Finally, a look at the future of space navigation is presented. The application and extension of current navigation concepts and of new navigation-enhancing technologies to the future requirements of robotic and manned space navigation systems are discussed.