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1
Mems technology quality requirement as applied to multibeam echosounder
100%
Bikonis K. , Demkowicz J.
Polish Maritime Research
|
2018
|
tom 25
|
nr 4
EN
Small, lightweight, power-efficient and low-cost microelectromechanical system (MEMS) inertial sensors and microcontrollers available in the market today help reduce the instability of Multibeam Sonars. Current MEMS inertial measurement units (IMUs) come in many shapes, sizes, and costs — depending on the application and performance required. Although MEMS inertial sensors offer affordable and appropriately scaled units, they are not currently capable of meeting all requirements for accurate and precise attitudes, due to their inherent measurement noise. The article presents the comparison of different MEMS technologies and their parameters regarding to the main application, namely Multibeam Echo Sounders (MBES). The quality of MEMS parameters is crucial for further MBES record-processing. The article presents the results of undertaken researches in that area, and these results are relatively positive for low-cost MEMS. The paper undertakes some vital aspect of using MEMS in the attitude and heading reference system (AHRS) context. The article presents a few aspects of MEMS gyro errors and their estimation process in the context of INS processing flow, as well as points out the main difficulties behind the INS when using a few top MEMS technologies
2
Content available Inertial sensors applications in underwater measurements
100%
Bikonis K. , Demkowicz J.
|
2017
|
tom Vol. 20
13--18
EN
Over the past decades microelectromechanical systems (MEMS) researchers have demonstrated a number of microsensors for almost every possible sensing modality, including attitudes. Current MEMS inertial measurement units (IMU) come in many shapes, sizes, and costs — depending on the application, and performance required. MEMS sensors have proved and demonstrated performance exceeding those of their macroscale counterpart sensors. In the paper chosen IMU applications in underwater measurements are presented. First, for reduction of instability of the underwater sensor during measurements, like multibeam echosounder system (MBES), where the MEMS parameters’ quality are crucial for further MBES record-processing. Second, in underwater navigation systems, for determining the position of underwater vehicles, like Remotely Operated Vehicles (ROV) and, more recently, Autonomous Underwater Vehicle (AUV) or to improve other positioning methods.
3
Wizualizacja w języku VRML przemieszczania się ryb pelagicznych w wiązce echosondy
100%
Bikonis K. , Moszyński M.
Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne
|
2003
|
tom nr 1
1--7
PL
Język wizualizacji wirtualnej rzeczywistości VRML (ang. Virtual Reality Modeling Language) obok typowych aplikacji w grafice komputerowej znalazł również zastosowanie w wiciu dyscyplinach naukowych. Przykładowo, w chemii stosuje się go do zobrazowania modeli atomowych cząsteczek, w medycynie do wizualizacji organów ludzkich, w astronomii do przedstawienia ruchu planet, a w geografii i nawigacji do tworzenia map. W poniższym artykule przedstawiono koncepcję tworzenia wirtualnego echogramu z danych pomiarowych pochodzących z przeszukiwań akustycznych. Ponieważ współczesne echosondy naukowe z rozszczepioną wiązką (ang. split beam) pozwalają jednoznacznie określać pozycję celów w toni wodnej, możliwa jest ich trójwymiarowa wizualizacja. Wykorzystując wbudowane mechanizmy języka VRML w stosunkowo łatwy sposób można zobrazować proces przemieszczania się ryb wraz z jednoczesną analizą echa. Dodatkowo, ponieważ współczesne przeglądarki WWW posiadąją możliwość interpretacji języka VRML, wyniki badań można udostępniać i prezentować w sieci Internet.
EN
Virtual Reality Modeling Language VRML despite the typical application in computer graphics is also used in various fields. For instance in chemistry it is used for visualization of atom particles, in medicine for modeling of human organs, in astronomy for visualization of trajectories of the stars and in geography and navigation for creation of 3D maps. In the paper the concept of creation of virtual echograms from the data acquired in acoustical surveys is presented. As the modern split-beam echosounders allows for nonambiguous localization of targets in the water column, it is possible to visualize them in 3D coordinate system. Using built-in properties of VRML it is relatively easy to visualize movement of fishes in the echosonder's transducer beam. Additionally, as the WWW browser can be equipped with VRML plugin 3D fish visualization can be redistributed in the Internet.
4
Content available Seafloor relief reconstruction from side scan sonar data
100%
Łubiniewski Z. , Bikonis K.
Hydroacoustics
|
2007
|
tom Vol. 10
101-106
EN
Side scan sonar is one of the most widely used imaging systems in the underwater environment. It is relatively cheap and easy to deploy, in comparison with more powerful sensors. Although side scan sonar does not provide seafloor bathymetry directly, its records are directly related to seafloor images. In the paper, the method for 3D seafloor relief reconstruction from side scan sonar data is presented. The method is based on the Shape From Shading technique and for estimation of a bottom depth at a currently processed point, it uses the information from both currently processed and previous ping. The results obtained by several versions of the developed algorithm are presented. The obtained results are promising and also show how the performance of the proposed algorithm might be improved in further work.
5
Content available MEMS technology quality requirements as applied to multibeam echosounder
100%
Bikonis K. , Demkowicz J.
Polish Maritime Research
|
2018
|
tom nr 4
59--64
EN
Small, lightweight, power-efficient and low-cost microelectromechanical system (MEMS) inertial sensors and microcontrollers available in the market today help reduce the instability of Multibeam Sonars. Current MEMS inertial measurement units (IMUs) come in many shapes, sizes, and costs — depending on the application and performance required. Although MEMS inertial sensors offer affordable and appropriately scaled units, they are not currently capable of meeting all requirements for accurate and precise attitudes, due to their inherent measurement noise. The article presents the comparison of different MEMS technologies and their parameters regarding to the main application, namely Multibeam Echo Sounders (MBES). The quality of MEMS parameters is crucial for further MBES record-processing. The article presents the results of undertaken researches in that area, and these results are relatively positive for low-cost MEMS. The paper undertakes some vital aspect of using MEMS in the attitude and heading reference system (AHRS) context. The article presents a few aspects of MEMS gyro errors and their estimation process in the context of INS processing flow, as well as points out the main difficulties behind the INS when using a few top MEMS technologies.
6
Content available EGNOS-Based GNSS receiver for precise positioning in restricted areas
100%
Demkowicz J. , Bikonis K.
Hydroacoustics
|
2016
|
tom Vol. 19
65--73
EN
Positioning accuracy is very important in many areas, whereas the typical GPS receiver accuracy is often not sufficient. The European Geostationary Navigation Overlay Service (EGNOS), Europe’s first venture into satellite navigation, improves the open public service offered by the Global Positioning System (GPS). As a satellite navigation augmentation system, EGNOS improves the accuracy of GPS by providing a positioning accuracy to within 3 meters. In this paper we present GNSS receivers based on EGNOS, dedicated for precise positioning in restricted areas of continental shelf performance. The article presents some results regarding position accuracy, obtained for a few receivers in that context.
7
System monitorowania wybranych parametrów środowiska z wykorzystaniem sieci GSM
100%
Bikonis K. , Jaśkiewicz K.
Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne
|
2010
|
tom T. 19
245-250
PL
W artykule przedstawiony zostanie prototyp systemu monitorowania wybranych parametrów środowiska z wykorzystaniem sieci GSM. Aktualnie opracowany system jest w stanie monitorować temperaturę, ciśnienie, wilgotność względną, natomiast w docelowym systemie dodatkowo - prędkość i kierunek wiatru, wielkość opadów, nasłonecznienie oraz wysokość wód w zbiornikach wodnych. Akwizycja danych z rozproszonych stacji meteorologicznych odbywa się na serwerze głównym z wykorzystaniem kanału radiowego GSM. Każdy zalogowany w systemie użytkownik uzyskuje dostęp do stałych powiadomień e-mailowych oraz SMS o aktualnym stanie pogody, jak również poprzez przeglądarkę WWW do archiwalnych danych. Dzięki automatyzacji procesu powiadomień system może służyć nie tylko, jako serwis pogodowy, ale również w ograniczonym zakresie, jako system wczesnego ostrzegania o zagrożeniach meteorologicznych na danym obszarze.
EN
The prototype of environment parameters monitoring system using GSM system will be presented in the paper. The present worked-out system is monitoring the temperature, pressure, the wind speed and direction, however in the target system will be monitoring the relative humidity rainfall size, sun exposure and water level in water body. The data acquisition from the scattered weather stations is being done at the main server by the GSM radio channel. Each logged in user has the access the permanent e-mail notice and the SMS about the actual weather, but also to the archive data through WWW browser. Thanks to the automatisation of the notification process the system can be used not only as a weather services, but also in the limited range as an early alert to the weather risk system at the given area.
8
Instalacja i wstępna analiza danych batymetrycznych pochodzących z echosondy wielowiązkowej
100%
Demkowicz J. , Bikonis K.
Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne
|
2005
|
tom T. 7
495-502
PL
W akustycznym telemonitoringu środowiska morskiego stosowane są dwa rodzaje sonarów, a mianowicie: sonary boczne i echosondy wielowiązkowe. Oba systemy dostarczają danych zarówno dla batymetrii, jak i dla akustycznego obrazowania dna morskiego. Echosondy wielowiązkowe są zaawansowanymi technologicznie urządzeniami, które dzięki wielokierunkowej obserwacji szerokokątnej dna, przy jednoczesnym utrzymaniu wysokiej rozdzielczości kątowej, pozwalają na doskonałą batymetrię i obrazowanie dna morskiego z odbieranych sygnałów echa. Artykuł prezentuje rezultaty instalacji, uruchomienia i wstępnej analizy danych uzyskanych z rzeczywistych pomiarów batymetrycznych za pomocą wysokorozdzielczej echosondy wielowiązkowej firmy Konsgberg. Zaprezentowano również sposoby prezentacji danych, główne źródła błędów oraz sposoby ich rozpoznawania.
EN
Multibeam sonar is an advanced technology for the seafloor mapping. The paper presents Some technical aspects of multibeam processing technology, sources and types of errors and finaly 3D vizualization of raw data acquired by multibeam echosounder EM 3002.
9
Content available Data Integration from GPS and Inertial Navigation Systems for Pedestrians in Urban Area
100%
Bikonis K. , Demkowicz J.
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
|
2013
|
tom Vol. 7, no. 3
401--406
EN
The GPS system is widely used in navigation and the GPS receiver can offer long-term stable absolute positioning information. The overall system performance depends largely on the signal environments. The position obtained from GPS is often degraded due to obstruction and multipath effect caused by buildings, city infrastructure and vegetation, whereas, the current performance achieved by inertial navigation systems (INS) is still relatively poor due to the large inertial sensor errors. The complementary features of GPS and INS are the main reasons why integrated GPS/INS systems are becoming increasingly popular. GPS/INS systems offer a high data rate, high accuracy position and orientation that can work in all environments, particularly those where satellite availability is restricted. In the paper integration algorithm of GPS and INS systems data for pedestrians in urban area is presented. For data integration an Extended Kalman Filter (EKF) algorithm is proposed. Complementary characteristics of GPS and INS with EKF can overcome the problem of huge INS drifts, GPS outages, dense multipath effect and other individual problems associated with these sensors.
10
Content available MEMS technology quality requirements as applied to multibeam echosounder
100%
Demkowicz J. , Bikonis K.
Hydroacoustics
|
2016
|
tom Vol. 19
75--82
EN
Small, lightweight, power-efficient, and low-cost microelectromechanical system (MEMS) inertial sensors and microcontrollers, available in the market today, help reduce the instability of Multibeam Sonars. Current MEMS inertial measurement units (IMUs) come in many shapes, sizes, and costs — depending on the application and performance required. Although MEMS inertial sensors offer affordable, appropriately scaled units, they are not currently capable of meeting all requirements for accurate and precise attitudes, due to their inherent measurement noise. The article presents the comparison of different MEMS technologies, and their parameters regarding to the main application; namely, Multibeam Echo Sounders (MBES). The MEMS parameters’ quality are crucial for further MBES record- processing, the article presents the results of undertaken researches in that area, and the results are relatively positive for low-cost MEMS.
11
Content available 3D seafloor reconstruction using data from side scan and synthetic aperture sonar
100%
Bikonis K. , Łubniewski Z.
Hydroacoustics
|
2010
|
tom Vol. 13
25-30
EN
Side scan and synthetic aperture sonars are widely used imaging systems in the underwater environment. They are relatively cheap and easy to deploy, in comparison with more powerful sensors, like multibeam echosounders. Although side scan and synthetic aperture sonars does not provide seafloor bathymetry directly, their records are finally related to seafloor images. Moreover, the analysis of such images performed by human eye allows creating semi-spatial impressions of seafloor images obtained from side scan sonar echograms. In the paper, some techniques for 3D seafloor shape reconstruction from side scan and synthetic aperture sonars are presented. They are based on Shape From Shading (SFS) approach, which is one of classical problems in computer vision. The method for reconstruction of 3D seafloor relief using the information from both the currently processed and previous ping is presented. The advantage of the presented methods is their simplicity and the ability to produce the results within sequential, i.e. “one run” processing of side scan sonar image. Another algorithm relies on estimating the altitude gradient of the insonified surface from sonar data, combined with the use of dimension of shadow areas for estimation of the current elevation change. The presented results are promising and also show to some extent how the performance of the proposed algorithm might be improved in further investigation.
12
Content available 3D reconstruction of seafloor from side-scan records
100%
Bikonis K. , Moszyński M.
Hydroacoustics
|
2005
|
tom Vol. 8
9-14
EN
The modern underwater acoustic equipment, like multibeam sonar, is able to provide the data which allows for unambiguous localization and also 3D visualisation of targets of different kinds, including wrecks, mines and other submerged objects. The large amount of information that seems to be useful for this purpose, could also be extracted from side-scan sonar data, which has been collected over years within different survey regions. In this context, the paper concerns the development of side-scan data processing method for 3D reconstruction of seafloor and its imaging. In this paper, two novel approaches are proposed. The first utilises the more accurate models of backscattering, including the differences in signatures of several types of objects. The second is based on definition and investigation of some quantitative descriptors of geometric features expected to be found in images of localised objects of artificial origin. The preliminary results obtained by application of these techniques to side-scan sonar data processing will be discussed in this paper.
13
Content available 3D imaging software tools for multibeam sonar data
80%
Bikonis K. , Moszyński M. , Chybicki A. , Kociński P.
Hydroacoustics
|
2006
|
tom Vol. 9
17-22
EN
Nowadays, the techniques for 3D computer graphics are developing dynamically. They are finding application not only for creating computer games, but often for three-dimensional data visualization systems. Applying these techniques make graphical operations more effective and consequently these systems are more efficient. The paper presents the system for 3D seafloor visualization using multibeam sonar data. In the presented system three programming techniques for 3D graphic were used C++ OpenGL, Java3D, Java OpenGL. The problems related to the system development and the ways of its solution are presented.
14
Dedykowany System Informacji Przestrzennej w kontekście ochrony infrastruktur krytycznych
80%
Kulawiak M. , Bikonis K. , Stepnowski A.
Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne
|
2008
|
tom T. 15
73-78
PL
Nowe zaawansowane narzędzia Technologii Informacyjnych i Komunikacyjnych mogą stanowić bardzo użyteczną pomoc podczas przewidywania różnego rodzaju zagrożeń jak również minimalizacji związanego z nimi ryzyka. Artykuł prezentuje Sieciowy System Informacji Przestrzennej dla Szacowania i Wizualizacji Infrastruktur Krytycznych i ich Zagrożeń, stworzony dla Urzędu Miejskiego w Gdańsku przez Politechnikę Gdańską. System ten jest przeznaczony do przetwarzania przestrzennego i mapowania wyników różnych analiz Infrastruktur Krytycznych, zaś CARVER2TM pełni w nim rolę głównego "sensora". System ten oferuje zintegrowane środowisko do wizualizacji scenariuszy zagrożeń jak również narzędzia pracy grupowej pozwalające na wymianę informacji pomiędzy odległymi fizycznie centrami decyzyjnymi. Artykuł opisuje również przykładowe zastosowanie syste-mu do wizualizacji i mapowania rezultatów wybranych analiz Infrastruktur Krytycznych w rejonie Trójmiasta.
EN
As useful aid in predicting different kinds of hazards and minimizing the associated potential risks are taken the newly developed advanced tools of Information and Communication Technologies (ICT). One example of such tool is the recently developed CARVER2TM. It allows for comparing dissimilar types of Critical Infrastructure (CI) using the same standards but does not yet provide visual presentation of the results nor their possible interac-tions in the geographic context. The paper presents a Web-Based Geographic Information System for Assessment and Visualization of Critical Infrastructure and its Hazards which was developed by the Gdansk University of Technology for the City i of Gdansk. The system was created for spatial processing and mapping of various CI analysis results, with the CARVER2TM as its basic "sensor". It works as an integrated solution for both visualization of critical scenarios and a team-enabled environment for information analysis and sharing among geographically distributed decision makers. The paper also focuses on the sample application of the modified system with reference to the visualization and mapping of the distribution of critical infrastructure components in the ports of the Tricity.
15
Content available Mobile inventory system for hydrotechnical objects using data from multiple sensors operating simultaneously
80%
Krawczyk J. , Bikonis K. , Dominik W.
Hydroacoustics
|
2016
|
tom Vol. 19
239--250
EN
The knowledge of the location, shape and other characteristics of spatial objects in the coastal areas has a significant impact on the functioning of ports, shipyards, and other waterinfrastructure facilities, both offshore and inland. Therefore, measurements are taken of the underwater part of the waterside zone, which means the bottom of water and other underwater objects (e.g. breakwaters, docks, etc.), and objects above the water, such as the above-water part of the waterside, breakwaters, hydraulic constructions, and other objects of the waterside infrastructure. In this paper, a project of a mobile inventory system for hydrotechnical objects using data from multiple sensors operating simultaneously will be presented. The aim of the project is to elaborate a mobile underwater scanning system which could be applied in various works requiring precise, detailed and coherent, underwater and above-water measurement, especially in areas associated with surveying, inspection and monitoring of objects in coastal areas. To elaborate the concept of the system, analysis concerning existing methods of precise underwater and above-water measurement, as well as the measuring equipment available, was carried out. The results of the research were used to develop the concept of a mobile system equipped with underwater laser scanning and acoustic positioning. The technology demonstration was developed using a specially-built laboratory environment that simulates hydrotechnical infrastructure with access to GPS data. The final stage of the project will consist of testing the system in open waters.
16
Trójwymiarowa wizualizacja obiektów na dnie morskim z zastosowaniem technik wirtualnej rzeczywistości
80%
Bikonis K. , Moszyński M. , Stepnowski A.
Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne
|
2004
|
tom T. 5
883-890
PL
Wśród wielu nowatorskich technik stosowanych do wizualizacji danych pomiarowych coraz większą rolę odgrywają te oparte na językach opisu wirtualnej rzeczywistości. Język VRML (ang. Virtual Reality Modeling Language), należący do grupy języków opisu wirtualnej rzeczywistości, stosowany jest z powodzeniem w tak różnych dziedzinach jak chemia, medycyna, geografia, astronomia i nawigacja. Głównym celem artykułu jest pokazanie przydatności tego języka w tworzeniu trójwymiarowego obrazu dna morskiego i obiektów leżących na dnie. W niniejszym artykule został zaprezentowany sposób tworzenia trójwymiarowego obrazu na podstawie danych pochodzących z echosondy wielowiązkowej. Współczesne echosondy wielowiązkowe umożliwiają lokalizację celu w trójwymiarowym układzie współrzędnych, co w połączeniu z wbudowanymi mechanizmami języka VRML pozwala na wizualizację położenia wraków, min i innych obiektów znajdujących się w toni wodnej. Dodatkowo, przeglądarka WWW wyposażona w odpowiednie rozszerzenie umożliwia dystrybucje wirtualnej sceny w sieci Internet.
EN
Virtual Reality Modeling Language VRML despite the typical application in computer graphics is also used in various fields. For instance in chemistry it is used for visualization of atom particles, in medicine for modeling of human organs, in astronomy for visualization of trajectories of the stars and in geography and navigation for creation of 3D mars. In the paper VRML is used for visualization of ship wracks located on the sea floor. Developed algorithm creates 3D active images from acoustic data acquired by a multibeam sonar. As the modern multibeam echosounders and sonars allows for unambiguous localization of seafloor targets, it is possible to visualize wracks, mines and other submerged objects in 3D coordinate system using built in properties of VRML. Additionaly, as the WWW browser can be equipped with VRML pluging 3D visualization of objects can be redistributed in the Internet.
17
Application of shape from shading technique for side scan sonar images
80%
Bikonis K. , Moszynski M. , Lubniewski Z.
Polish Maritime Research
|
2013
|
tom 20
|
nr 3
EN
Digital signal processing technology has revolutionized a way of processing, visualisation and interpretation of data acquired by underwater systems. Through many years side scan sonars were one of the most widely used imaging systems in the underwater environment. Although they are relatively cheap and easy to deploy, more powerful sensors like multibeam echo sounders and sonars are widely used today and deliver 3D bathymetry of sea bottom terrain. Side scan sonar outputs data usually in a form of grey level 2D acoustic images but the analysis of such pictures performed by human eye allows creating semi-spatial impressions of seafloor relief and morphology. Hence the idea of post-processing the side scan sonar data in a manner similar to human eye to obtain 3D visualisation. In recently developing computer vision systems the shape from shading approach is well recognized technique. Applying it to side scan sonar data is challenging idea used by several authors. In the paper, some further extensions are presented. They rely on processing the backscattering information of each footprint (pixel in sonar image) along with its surroundings. Additionally, a current altitude is estimated from the size of shadow areas. Both techniques allow constructing 3D representation of sea bottom relief or other investigated underwater objects
18
System GIS czasu rzeczywistego do zdalnego monitorowania zanieczyszczeń w środowisku morskim
80%
Łubniewski Z. , Partyka A. , Bikonis K. , Moszyński M.
Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne
|
2005
|
tom T. 7
483-488
PL
W artykule przedstawiono koncepcję oraz prototyp morskiego systemu GIS do zdalnego monitorowania w czasie rzeczywistym zanieczyszczeń środowiska morskiego. System pozwala na gromadzenie i integrowanie różnych typów danych dotyczących zanieczyszczeń, pozyskiwanych na bieżąco za pomocą wielorakiego rodzaju sensorów (echosond, sond CTD), jak również zdjęć satelitarnych i lotniczych. Zadaniem systemu jest wizualizacja, także trójwymiarowa, oraz mapowanie zanieczyszczeń, takich jak plamy ropy naftowej czy zalegające na różnych głębokościach skupiska odpadów przemysłowych, a także wieloaspektowe przetwarzanie i analiza tych danych pozwalające na predykcję zachowania się skupiska zanieczyszczenia w najbliższej przyszłości. System do przechowywania danych wykorzystuje bazę danych w standardzie SQL z rozszerzeniem o możliwość przechowywania danych przestrzennych (Spatial Extention), natomiast do zdalnej wizualizacji obiektów w kontekście geograficznym używane są języki SVG (ang. Scalable Vector Graphic) i VRML (ang. Virtual Reality Modeling Language). Po stronie klienta system wymaga jedynie przeglądarki stron WWW wyposażonej w rozszerzenia SVG i VRML.
EN
The paper presents the concept and the prototype of safety-related application of the newly developed real-time, remotely accessible marine GIS for water pollution monitoring and emergency management supporting. The system is able to integrate many different types of marine pollution survey data. The system supports the instantaneous multi aspect data management and analysis, and the prediction of the pollutants behavior. The system utilises the SQL database for data storage and the SVG and VRML languages for geographical objects remote presentation, and requires only the WWW browser with SVG and VRML plug-in.
19
Content available Integrated acoustical-optical system for inventory of hydrotechnical objects
80%
Bikonis K. , Krawczyk J. , Stepnowski A.
|
2017
|
tom Vol. 20
19--28
EN
The knowledge of the location, shape and other characteristics of spatial objects in the coastal areas has a significant impact on the functioning of ports, shipyards, and other waterinfrastructure facilities, both offshore and inland. Therefore, measurements of the underwater part of the waterside zone are taken, which means the bottom of the water and other underwater objects (e.g. breakwaters, docks, etc.), and objects above the water, such as the above-water part of the waterside, breakwaters, hydraulic constructions, and other objects of the waterside infrastructure. In this paper, project results of an integrated acoustical-optical system for inventory of hydrotechnical objects are presented. The aim of the project was to elaborate a mobile underwater scanning system which could be applied in various works that require precise, detailed and coherent, underwater and above-water measurement, especially in areas associated with surveying, inspection and monitoring of objects in coastal areas.
20
Content available Reconstruction of 3D shape from sidescan sonar images using shape from shading technique
80%
Moszyński M. , Bikonis K. , Łubniewski Z.
Hydroacoustics
|
2013
|
tom Vol. 16
181--188
EN
Side scan sonar (SSS) is one of the most widely used imaging systems in the underwater environment. It is relatively cheap and easy to deploy in comparison with more powerful sensors like multibeam echosounder or synthetic aperture sonar. Although, the SSS does not provide directly the seafloor bathymetry measurements. Its outputs are usually in a form of grey level acoustic images of seafloor. However, the analysis of such images performed by human eye allows creating semi-spatial impressions on seafloor relief and morphology. The 3D shape reconstruction from 2D images using SFS approach is one of classical problems in computer vision. In the paper, the method based on Shape From Shading (SFS) technique for SSS images processing is presented. The 3D seafloor relief is reconstructed using the information from both the currently processed and previous ping. The seafloor backscattering coefficient dependence on an incident angle, which is needed in the applied SFS algorithm scheme, is being estimated in the experimental way, i.e. by analysis of SSS image contents for the flat seabed region.
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