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1
Content available Investigation of the underwater noise associated with remotely-operated vehicles
Buszman K., Mironiuk W.
Zeszyty Naukowe Akademii Morskiej w Szczecinie
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2018
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nr 54 (126)
129--132
EN
There is increasing demand for various types of submersible and floating remotely-operated vehicles which have herein been studied with respect to the threats posed by these kinds of objects. Local physical field disorder analyses have demonstrated the possibility of detecting and classifying objects based on hydroacoustics. Hydroaocoustic analysis results are presented as narrowband and One-Third-Octave spectra of different types of remotely-operated vehicles. Investigations were performed using an underwater measuring system located in very shallow water in a coastal zone characterized by conditions considered as poor for sound propagation.
2
Content available Passive hydroacoustic method of detection and tracking object moving on the sea surface and floating in the depth
Szymczak W., Buszman K.
Hydroacoustics
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2017
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Vol. 20
173--178
EN
The main goal of the paper is to present passive, autonomous system to observe objects moving on the sea surface and floating in the depth prepared to work in very shallow water. Complete system will be described starting from hardware realization finalizing on configuration of sensors and presentation of algorithms implemented in prepared to this project software ( alarm types, setting parameters responsible for alarm generation etc.). Finally example of object detection will be presented concentrating on remotely operate vehicles ROV – seabotix and combustion motorboat. At a given point of discussion, stability of algorithms eliminating the occurrence of false alarms will be presented.
3
Content available Acoustic analysis of remote-controlled surface and underwater vehicles
Buszman K., Szymczak W., Mironiuk W.
Hydroacoustics
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2017
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Vol. 20
29--34
EN
Technological progress has made the use of remotely controlled objects moving on the surface and underwater, for a variety of purposes, become extraordinarily popular. The widespread use of such vehicles enables unauthorized use. Therefore, knowledge of the hydroacoustic field characteristics makes it possible to identify by passive underwater observation systems. The paper presents the results of narrowband and one-third-octave frequency analyzes of remote-controlled surface and underwater vehicles. The change in sound pressure was recorded for vehicles moving a short distance away from the hydrophone. The research was carried out in difficult conditions, propagation, at a small depth in the coastal zone.
4
Content available Signals parametrization method of sailing vessels
Buszman K., Gloza I.
Hydroacoustics
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2016
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Vol. 19
27--36
EN
The expansion of maritime transport is directly connected with increased risk of the appearance of unidentified vessels in the approaches to ports, wind farms, and other sensitive places in the water-body. Creating a parameters database of sailing objects, based on recorded dynamic variations of different physical fields with the specified aims of increasing security within the strategic offshore areas.
5
Content available The one – third – octave spectrum as a method of vessel identification
Gloza I., Józwiak R., Buszman K.
Hydroacoustics
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2014
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Vol. 17
63--68
EN
The subject of the examinations carried out is hydroacoustic noise in coastal zones. Under these conditions natural noise and the noise from moving vessels affect each other, as well as interference from industrial infrastructure located close to the coast. Both natural noise and noise caused by human activity affect the detection and identification of noise sources in these conditions. Experiments have been performed by the mobile measuring module in the Gulf of Gdansk. This showed that it can extract spectrum components, based on the results of underwater noise. These components allow the detection of moving objects. The collected database of measurements enabled the comparison of one-third-octave spectra of three different ships. The components specific to the type of vessel could extracted as a result of comparison. Consequently one of the three tested vessels could be identified.
6
Content available Sound intensity distribution as an underwater acoustic investigation process
Gloza I., Buszman K.
Hydroacoustics
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2014
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Vol. 17
57--62
EN
The subject matter of this research is underwater noise generated by sailing vessels in shallow seas. The classical method for measurement of underwater noise involves measuring effective acoustic pressure and fits for purposes in the free far field of the source. Despite its popularity, the method does have some significant limitations. Investigations of underwater noise generated by moving vessels in shallow seas are almost solely confined to the near field. In addition, this has a high level of interference and numerous wave reflections. This is why, as well as using the acoustic pressure measurement method, a complementary method for measuring acoustic wave intensity is used increasingly often. The measurements were taken using an underwater measurement module equipped with a set of detectors. Submerged at 20m, the object moved along a designated trajectory at a preset speed (as determined by the parameters of the ship’s machinery). Because all of the on-board equipment generates ship-specific noise, additional measurements were taken of the vibrations generated by selected ship’s machines to identify those sources. If known, the distribution of the acoustic field from vessels helps to identify the characteristic frequencies generated by the ship’s equipment and machinery. The paper includes a comparison of acoustic wave intensity and acoustic pressure measurements taken under the same ambient conditions and over the same period.
7
Content available Examination of acoustic wave propagation in real conditions
Buszman K.
Hydroacoustics
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2013
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Vol. 16
11--18
EN
Elastic waves are the primary transmission medium in water environment. Acoustic waves are not as strongly attenuated as electromagnetic waves. Sound is used in all kinds of underwater communication systems and sonar devices. Starting from a simple single beam sonar to multi-beam hydrographic echosounders. Thus the issue of the phenomenon of sound propagation in water is the base for understanding the work of underwater hydroacoustic systems[1].
8
Content available The multi-influence passive module for underwater environment monitoring
Gloza I., Buszman K.
Hydroacoustics
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2011
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Vol. 14
47-54
EN
The threats to the operation of a ship close to the coast and harbor can be significantly different to those of deep-water operation. It is obvious that any operation in this environment requires a good understanding of how the ship’s signatures behave. Quite a few different systems exist which can detect and track underwater moving targets. The most practical systems use underwater passive detectors. Therefore we often install in such environment multi-sensor measuring device to verify the whole situation. Designed by the Polish Naval Academy mobile multi-sensor module serves such purpose. This module consists of acoustic, magnetic, electric, seismic and pressure sensors fitted to the nonmagnetic tripod. This makes possible to measure signatures to high degree of accuracy in a variety of environments in real time.
9
Content available Composition of data visualisations by sub-bottom profiler and multibeam echosounder in MATLAB
Grelowska G., Kozaczka E., Buszman K.
Hydroacoustics
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2010
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Vol. 13
101-108
EN
This paper contains description of procedure, which was elaborated in a numerical computing environment Matlab. The result of these procedures is a graphical composition of images obtained from two different hydroacoustic devices. It enables to compare different types of visualisations for the same geographical position and simultaneous work with graphical representation of all data types.
10
Content available Examination of the co-operation between echosounder and motion sensor during sea trials
Szymczak W., Buszman K.
Hydroacoustics
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2009
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Vol. 12
217-226
EN
Sea trials with parametric echosounder SES-2000 Compact needs precise information about sounded area of the seafloor. Because of narrow beam both in horizontal and vertical surface each change of antenna position have high influence for results and analyze of measured data. Vessel has to be equipped with a special device, such as multibeam echosounder, to obtain more information about seafloor sounding which is an addition for basic measurements units. Information about bottom topography, from where sounding pulse comes, may give many useful data necessary to correct analyze by echosounder user. There are also parameters such as roll, pitch and heave, which have to be complied. These variables have an influence for shape and echo level. The last parameter analyzed in this article is a difference between vessels heading and bearing. This information comes from heading sensor and GPS receiver.
11
Content available Laboratory to measure directivity characteristics of arrays
Grelowska G., Szymczak W., Buszman K.
Hydroacoustics
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2008
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Vol. 11
381-388
EN
The paper presents the laboratory station to measure directivity characteristics of narrow beam sonar's and echo sounder's antennas. It will be describe method of collecting samples from surface, unit used to precise positioning receiving hydrophone, construction and use of rack to direct main beam in exact direction. Additionally we show station to measure drift of the sea bottom impedance.
12
Content available Laboratory model of high frequency sonar
Buszman K., Szymczak W.
Hydroacoustics
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2008
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Vol. 11
39-46
EN
This article contains the construction and laboratory application of high frequency sonar model. In view of working in laboratory conditions, they must be fulfilled succeeding parametric cases: very narrow beam, low level of side lobes and low acoustic power of transmitted impulse sounding. When all of these conditions are fulfilled, it makes possible the explanation to students some terms like depth, angular resolution and making clear, that water is the best environment to acoustic waves transmission. Furthermore, there is used automatic component, namely rotary antenna, which make possibility to precision area scanning.
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