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Development of sea state registration and analysis

1. Wave Height and Period Analysis Software WHAPAS 1 Introduction 1 1 Scope and purpose This document describes the Wave Height and Period Analysis Software solution called WHAPAS explaining the purpose architecture and functionality by software component Description and results of the verification experiments performed in 2010 are provided The WHAPAS software system is intended for shore side calculation of significant wave height in the marine areas where navigational buoys equipped with TelFiCon GSM GPRS telematics units implementing 3 axial acceleration measurement are deployed WHAPAS calculates the wave heights based on the buoy acceleration data and individual parameters of equipment used sensor calibration and buoy model and stores them in a database or files WHAPAS output data 1s pre formatted to be utilised for provision of an e Navigation service of broadcasting the calculated wave heights over the AIS shore side network using AIS M8 hydro meteorological data messages This requires application of an external software component developed by Cybernetica AS AIS Router with Hydrometeorological Data Module Wave period is not analysed by the current implementation of WHAPAS The WHAPAS software was developed by Cybernetica AS in cooperation with the Estonian Maritime Administration and the Marine Systems Institute of the Tallinn University of Technology within the framework of the Efficient Safe and Sustainable Traf
2. a i u ZC D g 56 04 10 15 20 25 30 Longitude deg Figure 2 Significant wave height during storm Gudrun on January 9 06 00 UTC Results from wave model SWAN Scale on color bar is in meters In next chapters from 1 1 to 1 3 we give answers to some most important questions needed to be clarified in order to establish a link between the wave parameters measured with acceleration sensors on board of navigation buoys and wave parameters registered with pressure based probe as well as modeling results showing wave field realizations in certain sea areas at given time moments forced by atmospheric conditions 1 2 Depth dependence of wave parameters Three physical processes contribute to the evolution of wind waves over basin of variable depth and size The first is the generation of wind waves by wind secondly the nonlinear transfer of wave energy between harmonics which allows for the generation of longer waves and lastly the dissipation which is the sum of whitecapping bottom friction and depth induced wave breaking The dissipation due to whitecapping is always present no matter how deep the sea is However depth induced breaking and bottom friction becomes important only in shallow waters and also depends on the wave period The bottom slope is important as well Numerical experiments with the wave model SWAN indicate that in Estonian coastal regions bottom friction becomes important in water depths less than 30m an
3. 1 Figure 1 with an E9264 circuit board inside and of a combined GSM GPS magnetic mount antenna TecSys AU 3S GSM Figure 2 with GSM and GPS cables of 2m to 5m length Typically an E9264 is supplied in integrated form within some of LED lanterns manufactured by Cybernetica AS offering better protection from environmental factors The E9263 1 module is intended for use during short term experiments onboard a navigational buoy to determine buoy movement by the means of registering accelerations in three axes of the buoy sampling the outputs of a three axial micromechanical accelerometer sensor mounted on the E9264 circuit board and sending measurement values to the TeViINSA centre for processing The module is designed for installation inside an equipment container compartment of a navigational buoy protecting the module from direct contact with salt water and mechanical factors 3 3 3 The E9264 circuit board is housed within a rectangular ABS plastic enclosure of gray colour with screw terminals and coaxial cable receptacles located on the right side Part financed by efficiensea org 47 Fa the European Union Z AS cin EfficienSea amp Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea surface It mounts to flat surface with screw hole pattern 90 x 110 mm Figure 3 A metal carrier plate with application specific location of the mounting holes can be ordered 3 3 4 Direction of the acceleration sensor axes is
4. 27 10 2010 28 10 2010 29 10 2010 31 10 2010 01 11 10 02 11 10 04 11 10 05 11 10 06 11 10 08 11 10 09 11 10 10 11 10 12 11 10 17 00 00 50 08 40 16 30 00 20 08 10 16 00 23 50 07 40 03 40 PL 11 30 PL 07 20 EL 03 10 PL 11 00 PL 06 50 EL 02 40 PL 10 30 PL 06 20 EL Figure 19 Significant wave height as measured by acceleration sensor on navigation buoy NM159 blue and pressure sensor based probe red in Kuradimuna second measurement period Yellow line shows maximum wave height recorded by pressure probe In the Karbimadal bank the accelerometers also capture significant wave heights quite well but a drastic underestimation occurs in 4th November when speed of SW wind reached about 20m s This underestimation is nearly 0 8 m Fig 22 and may be an instrumental calculation algorithm efficiensea org 41 oy Part financed by the European Union RA AAAS YN ee EfficienSea Baltic Sea Region a Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea failure but can also be attributed to natural spatial variability of wave field in this particular case In that context there can be pure wave field deformation because of sea bottom topography as well as too small wave period that navigation buoys badly represent Still positive is that in this strong wave case where maximum wave height was reaching 1 8m in Karbimadal and 4m in Kuradimuna was at least in Karbimadal s case well captured by both measurement methods R
5. Bay as modeled with SWAN wave model Arrows indicate wave propagation directions A more localized impact of coastal morphology upon wind waves is seen on Fig 4 and 5 In the former case the shoaling and depth induced breaking of wind waves is described in the latter case the wave reflection and diffraction near vertical wall Note that the coast absorbs much of the incoming wave energy and reflection is negligible efficiensea org 24 By nanceea4 the European Union b e ee Z can EfficienSea amp Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea 2 Maramet K ik oliguisicld a Keats tua Figure 4 Wave shoaling and depth induced wave breaking at western coast of Tahkuna peninsula as seen aero photography Estonian Land Board ee a Lena ols a a i ped a ae 2 r i ZA eas r et A l 5 L g on ae j I 39204 004 0937 9 DA 4 e A at Be ae n ka D a N a os ote fie J i cet ee o hes z J i KAES ie Ka ha af KA Ar Nas Fs ae T r Theat y Fa i a ae 4 a a Pa GEH A Ar ae Pg DAS 3 Fr Hens an o Sa S L A O 2 ge ee es A rap lit s ae A a j 4 Bigs Pn ER ne we i eat ce ae ae lt CL IL ee ae NS r7 p Pa k A ek Fer 0 100 _ 200m wKoilksoiguscd kaitstud Figure 5 Complicated nature of multiply wave diffractions and reflections near Lehtma jetty as seen aero photography Estonian Land Board 1 4 Shape of the wave shape and particularly wave shap
6. Sea countries on 8 9 January 2005 significant wave height grow over 9m in the southern Baltic Proper and was over 7m in Estonian territorial sea according to SWAN wave model results Fig 2 In both cases regions of highest waves are located more or less in the same places one of those West from Estonian Archipelago Pattern in the Gulf of Finland is slightly different as filed of average wave heights show secondary maximum in the middle of the Gulf which is averaging result of westerly and easterly winds creating waves In reality wave field decay in the Gulf is going easterly in case of westerly winds and roughly vice versa with easterly winds as seen also on Fig 2 Measurement location in our case lay well inside the Gulf of Finland reflecting more wave conditions of the open Gulf in Kuradimuna and Muuga bay wave field in case of Karbimadal O 20 40 60 80 100 1 64 00 62 00 60 00 4 58 00 56 00 ome 54 00 12 00 16 00 20 00 24 00 28 00 Figure 1 Average significant wave height in the Baltic Sea Color bar of the scale is in cm Results from the wave model WAM efficiensea org 21 ea eee the European Union AAA E Effi amp nS o a Baltic Sea Region i j ca Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea 64 gi 0o P a S 62 lt D 5 4p a E D 80 E gt _ _
7. WHAPAS JAR file contains a tool called HSQL Database Manager http hsqldb org doc guide apf html that is intended for facilitating the work with the configuration database For meaningful use in addition to TCP IP network WHAPAS needs the following external infrastructure to be operational and properly configured e TeViNSA system software with AtoN equipment settings and operational information database e TelFiCon telematics units mounted on navigational buoys regularly uploading buoy acceleration data to the TeViNSA server e AIS Router with Hydrometeorological Data Module and a functional shore side AIS network for broadcasting of M8 messages to the mariners Both input and output data of WHAPAS are in the form of files and database records Due to the fact that WHAPAS operates practically in the background outside of human efficiensea org 9 ne 9 the European Union ss r ah EfficienSea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea operator s attention it is recommended to establish automated monitoring of WHAPAS performance specifically in case when AIS M8 broadcasts are activated WHAPAS is equipped with plug ins for integration with open source software for online computer network monitoring Nagios http www nagios org 2 2 WHAPAS Architecture The WHAPAS Wave Height And Period Analysis Software software distribution consists of six separate software components that are
8. an AIS Router that regularly scans the output directory of the ROSC In addition output data can be saved to the TeViNSA AtoN database and even to a specified CSV file efficiensea org 12 Ee nace the European Union r B Itic Sea Region EfficienSea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea of yt se se N Loo TER A simplified diagram of the ROSC is provided in Figure 4 Wave height values received from the WCSC are processed to evaluate their correctness and if found to be correct the values are transferred to the post processing software module Figure 5 that divides the data set using a discrete step of 10 minute time intervals applies buoy specific individual correction factors and filters the results in the form of averaging over a two hour time period to suppress the noise The correction factors for a specific buoy need to be derived in advance from the comparison of a set of wave height calculation results obtained from WHAPAS with time matched results of nearby reference measurements recorded during the calibration process of a buoy In addition to the hydrodynamic properties of a specific buoy hull the calculation results may be influenced by the length and type of the mooring water depth in the deployment area and distance from coastal structures WHAPAS provides the capability to prepare a set of reference wave height measurement data set time matched to the results of its ow
9. and Sustainable Traffic at Sea se se i a 40 ofa Lee ea TER corresponding files and the command prompt changing the configuration settings based on direct user input in terminal mode and updating of the current active settings with new settings 2 2 5 Log Management Software Component The Log Management Software Component LMSC shown as Logging in Figure 1 is responsible for management of all WHAPAS logs including saving of log records received from software components and regular archiving of log files based on pre configured time intervals or file size In addition LMSC monitors the WHAPAS operation for malfunctions and significant events providing the assigned maintenance personnel with timely e mail notifications Software components responsible for configuration and logging can service the core components only within the limits of a single Java virtual machine Therefore in case when WCSC and ROSC are run on a single server but on separate JAVA virtual machines they need separate instances of CMSC and LMSC to be run on corresponding virtual machines 2 2 6 Settings Synchronisation Software Component The Settings Synchronisation Software Component SSSC shown as Synchronisation in Figure 1 is a part of code responsible for copying of AtoN equipment data from the TeViNSA database into the configuration database of WHAPAS Apart from the other WHAPAS components SSSC is completely separated from t
10. marked on the top lid and side of the enclosure with stickers pointing out the direction of acceleration regarded as positive for measurement values registered on X Y and Z axes The sensor itself is located practically on the vertical centreline of the enclosure 25 mm to the centre from the outer right edge Figure 1 Electronics module of the TelFiCon E9263 1 Set view from above Part financed by efficiensea org 48 Pl the European Union oT is m m ff er EfficienSea Baltic Sea Region E l Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea 3 k 4 N e i a q ia ON if d T a Figure 2 GSM GPS antenna TecSys AU 3S GSM with magnetic mount supplied in the E9263 Set 3 4 ELECTRICAL SPECIFICATIONS 3 4 1 Power supply voltage 8 VDC to 20 VDC 3 4 2 Power consumption at 25 C is provided in Table 1 Table 2 Power consumption modes of TelFiCon E9261 Power a of GSM GPS submodules Current consumption at power supply mode SO OSM OPS sprodes voltage GPS incl 12 VDC 20 VDC antenna DOA a a a ON P lt 90 0 mA Transmission NOTE Both the GSM and GPS submodules are constantly powered mode 4 in acceleration measurement application with the power consumption increasing periodically Part financed by efficiensea org 49 Ea fi the European Union eo 5 e af j0 fe s Baltic Sea Region EfficienSea erer a ae r F A e
11. methods 06 36 1 8 1 Wave heights comparison for first measurement period 1 23 09 2011 000 0 36 1 8 2 Wave heights comparison for second measurement period 20 10 15 11 2011 40 1 9 Wave height comparison experiment general OUTCOME cccccesccesseeesseeeetseeeseeens 43 FF SC snore cae cicet ces pe eo eres seve eae E E oes cae cped aca vest pe cepe noe ced caesceedceadeereeeeaceeccase 45 APPENDIX 2 Different buoy types equipped with 3D acceleration SeNSOFS ccccee 46 APPENDIX 3 TelFiCon E9263 1 product data and user MANUAl cece eceseeeseeeeteeeeees 47 oe E E ole E A E E ee A ee eee 47 32 SAFETY INFORMATION oreren ETE 47 2S DESCRIPTION eenn EE E E S E eset ees 47 34 ELECTRICAL SPECIFICATIONS rras EE SN 49 3 5 CONTROL AND COMMUNICATION SPECIFICATIONS ccccccscsscsecseesecsseseesseeeeees 50 30 PHYSICAL SPECIFICATIONS ereen E E E EE 51 3 7 ENVIRONMENTAL CONDITIONS OF USE cccccccccscsscssesscsscsscesecssesecsessesseeeeseeeesees 52 3 8 INSTALLATION AND ELECTRICAL CONNECTIONS cccccccccsccsscssesscssssscseessesseeesees 52 3 9 CONTACT INFORMATION OF THE SUPPLIER c ccccccscssescsscessessesecsessecsseeeseeeesees 55 efficiensea org 6 Part financed 6 by the European Union va B Itic Sea Region EfficienSea aoe Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea Ve 10 i a ye of 4 Lee Mmowee
12. not recommended in borderline areas of GSM coverage 3 5 7 In addition to heel angle calculation and monitoring a TelFiCon can be used for monitoring and reporting of collisions detected when acceleration sensor output exceeds pre configured level 3 5 8 After implementation of the Firmware over the Air FOTA capability in 2010 in addition to the remote changing of settings the firmware of the TelFiCon E9263 1 can be updated in full from the remote monitoring centre over the GSM GPRS network connection in case of updated firmware version becoming available or significant change in mission objectives Table 2 Expected approximate gross data rates required for transfer of acceleration data from TelFiCon E926X to shore server over cellular IP network Data acquisition Data Samplin session acquisition Daily Monthly g initiation session gross gross data No Data acquisition interval interval length data rate rate and transfer mode minutes minutes kB hour MB day MB month ms 1 Continuous 50 ne fee eae ee 273 sampling sampling 2 Continuous 200 si haa an 2 3 70 sampling sampling 3 6 PHYSICAL SPECIFICATIONS 3 6 1 Maximum Height of E9263 1 65 mm 3 6 2 Maximum Width of E9263 1 133 mm 3 6 3 Maximum Depth of E9263 1 122 mm 3 6 4 Maximum Weight of E9263 1 excluding antenna 0 35 kg 3 6 5 Materials Part financed by efficiensea org 51 Fa the European Union aie EfficienSes Baltic Se
13. swell consists of wind generated waves that are not or hardly affected by the local wind at that time They have been generated elsewhere or some time ago Wind waves in the ocean are called ocean surface waves Five factors influence the formation of wind waves Wind speed Distance of open water that the wind has blown over called the fetch Width of area affected by fetch Time duration the wind has blown over a given area Water depth All these factors work together to determine the size of wind waves the greater each of the variables the larger the waves Waves are characterized by Wave height from trough to crest Wavelength from crest to crest Wave period time interval between arrival of consecutive crests at a stationary point Wave propagation direction Waves in a given sea area typically have a range of heights not a single number for height For weather reporting and for scientific analysis of wind wave statistics their characteristic height over a period of time is usually expressed as significant wave height This figure represents an average height of the highest one third of the waves in a given time period usually chosen somewhere in the range from 20 minutes to twelve hours or in a specific wave or storm system Given the variability of wave height the largest individual waves are likely to be about twice the reported significant wave height for a particular day or storm In the context of wave dynam
14. that the closer to the coastline wave field gets the more complicated and dynamics of waves become more active Latter is the case for shipping especially for navigation of smaller ships also for anchoring safety of bigger ships and ship maneuvers The Baltic Sea has a very complicated shape elongated to NE SW direction Baltic Proper W E directional Gulf of Finland almost round like Gulf of Riga and all these bordering the Estonian coastal sea It s obvious that the same wind generates very different wave fields in particular sea areas From navigational point of view wave information is essential for smaller ships navigation is prohibited with certain wave height for bigger ships restrictions for certain maneuvers apply Therefore collection of information about wave conditions is very important Most of historical wave data and information are however based on visual observations at hydro meteorological coastal stations and some limited amount observations form on board of ships All these visual observations are probably satisfactory to get basic wave statistics but can t be applicable operationally There exist some limitations in space and time wave measurements out in the sea from last couple of years but these are really snapshots of a couple of weeks long in some points and can t be enough to describe wave field On the other hand numerical modeling is improving very fast and principally applicable as in hind and forecast mo
15. used A 2n f D 6 where A Amplitude of the acceleration Expressing the displacement from formula 6 results in D A 7 Fae f 7 The amplitude of acceleration can be expressed as follows A G a 8 where g 9 80665m s Acceleration of free fall G Wie as Value of acceleration in g units measured by a TelFiCon mounted onboard a navigational buoy After inserting the expression 5 into formula 7 and performing necessary elementary calculations we arrive at the following simplified association between the measured acceleration and the corresponding water level displacement significant wave height was eases D ar g 9 The remaining analysis is performed by applying spectral analysis FFT with selected window functions to the selected subsets of the three arrays of acceleration values data arrays received from the TelFiCon units mounted onboard navigational buoys In addition due to the different low pass filtering behaviour of different buoy types a set of correction factors will be applied to compensate for deviations in several wave height ranges Such correction factors are in fact buoy model parameters that present a simple description of dynamic behaviour of a specific buoy type Currently the only way of determining these factors is conducting of reference measurements utilising precision wave height measurement equipment deployed by the side of the buoy subject to calibration for acquisitio
16. 09 10 11 09 10 12 09 10 14 09 2010 15 09 2010 16 09 2010 18 09 2010 19 09 2010 20 09 2010 22 09 2010 23 09 2010 05 10 EL 12 30PL 07 50PL 03 10 EL 10 30 EL 05 50PL O1 0EL 08 30EL 03 50PL 11 10 PL 06 30 13 50 21 10 04 30 11 50 19 10 02 30 09 50 Figure 15 Significant wave height as measured by acceleration sensor on navigation buoy NM157 blue and pressure sensor based probe red in Kuradimuna first measurement period Yellow line shows maximum wave height recorded by pressure probe Statistically two datasets from two different methods look well fitting with each other over the entire measurement period average difference in significant wave height comes in order of several cm s up to 10cm Still looking more detailed in differences of obtained significant wave heights for the first measurement period given on Fig 16 and 17 some more can be observed In Karbimadal reference wave measurements are compared with wave data from three neighboring navigation buoys and in Kuradimuna from two buoys see Fig 12 for location of navigation buoys In case of Karbimadal the best fit of two data series is achieved in case of NM186 which is actually the closest buoy to the wave measurement site difference not more than 0 2m during the whole period In general difference of significant wave height is biggest during the mentioned above severe storm In case of other buoys differences are up to 0 8m Fig 16 but obviously this is because of wave field spatial var
17. 1000 4 5 EN 61000 4 6 EN 61000 4 8 EN 61000 4 11 3 7 6 EMC emissions within the limits of EN 60945 p 9 EN55016 1 1 EN55016 1 2 EN55016 1 3 EN55016 1 4 3 8 INSTALLATION AND ELECTRICAL CONNECTIONS Part financed by efficiensea org 52 Fa the European Union te EfficienSes Baltic Sea Region Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea eo e af 4 YX fe 3 irar e BER 3 8 1 For obtaining best results at acceleration measurement it is recommended to mount the E9263 1 electronic module as close as possible to the centre of gravity of a navigational buoy with one of the side surfaces of the box strictly co aligned with the vertical axis of the buoy When possible it is recommended to mount the box horizontally label up upper drawing in Figure 3 this way the Z axis of the sensor registers the vertical movement Note To obtain correct results of the buoy heel angle calculation and shore based wave height measurement the settings of a TelFiCon need to be updated when the vertical axis is not Z ANTENNA Fa TELF ICON E9263 1 BATTERY Osa 2UYy MAX lt 24V NB Figure 3 TelFiCon E9263 1 dimensions and connections 3 8 2 Determine the suitable locations for installation of the E9263 1 and the antenna with unobstructed viewing of the sky for best GSM and GPS reception considering sufficiency of antenna and power cable lengths Do not bend the cables under
18. 11 04 09 2011 07 09 2011 11 09 2011 14 09 2011 17 09 2011 20 09 2011 23 09 Figure 16 Graph showing difference in significant wave heights in meters as measured by acceleration sensor of three different navigation buoys close to the wave measurement site in Karbimadal first measurement period efficiensea org 39 Fa fi the European Union Efficient Safe and Sustainable Traffic at Sea Part financed by ae EfficienS A cs aui clie cas Baltic Sea Region 7 ICI ad Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea linan ky ts Mi fo aya 14 01 09 2011 04 09 2011 07 09 2011 11 09 2011 14 09 2011 17 09 2011 20 09 2011 23 0 Figure 17 Graph showing difference in significant wave heights in meters as measured by acceleration sensor on navigation buoys close to the wave measurement site in Kuradimuna first measurement period 1 8 2 Wave heights comparison for second measurement period 20 10 15 11 2011 The second measurement period is characterized by intense wave activity especially at the Kuradimuna Bank Wind forcing the wave generation several times reach 20m s in average and once around Nov 10 even up to 25m s Wind direction was varying with somewhat dominating SW direction but the strongest wind events appeared from NE and other stronger wind blew from NW N sector In Kuradimuna the timing of both wave measurement time series compared to reference measurements are well coherent with eac
19. 3 1 2 The E9263 1 is designed for industrial institutional use in accordance with requirements of the standard Maritime navigation and radiocommunication equipment and systems General requirements Methods of testing and required test results EN 60945 in addition to European safety and EMC requirements Once installed on an aid to navigation AtoN object and powered up a TelFiCon interacts with the TeViNSA Telematics for Visual Navigation Situational Awareness remote control and monitoring centre at a pre programmed IP address 3 2 SAFETY INFORMATION 3 2 1 A TelFiCon is an extra low voltage device power supply voltage below 24 VDC and has no exposed metal surfaces subjected to voltages in relation to each other or the GND terminal A PE terminal is not present 3 2 2 During the installation of the set on the navigation aid structure attention should be paid to handling of the carrier plate edges if supplied in order to avoid damaging the skin 3 3 DESCRIPTION 3 3 1 The TelFiCon product family is designed at Cybernetica AS for implementing communication control and measurement functions in remote visual aid to navigation systems connected to the TeViNSA control and monitoring centre over public GSM 900 1800 GPRS based IP networks The TelFiCon architecture integrates a microcontroller running proprietary firmware with standard GSM and GPS sub modules and internal sensors 3 3 2 The set consists of an electronics module E9263
20. Graph showing difference in significant wave heights as measured by acceleration sensor on navigation buoys close to the wave measurement site in Kuradimuna second measurement period Ai a A AA M Am A a AA Te I ANMA a G M Alt A h Wd Bd AAS A EE IU o i O G Wave height m 20 10 2010 25 10 2010 30 10 2010 4 11 2010 9 11 2010 NM185 NM186 Figure 22 Graph showing difference in significant wave heights as measured by the acceleration sensor on navigation buoys close to the wave measurement site in Karbimadal second measurement period 1 9 Wave height comparison experiment general outcome As these two measurement periods showed general rating to the wave height data coming from the navigation buoys equipped with acceleration sensors is SATISFACTORY Idea with the experiments was to make comparison of wave data from navigation sensors with data from pressure based wave probe data both measurements made in very close vicinity of navigation buoys at Kuradimuna and Karbimadal Open sea conditions Gulf of Finland were represented by efficiensea org 43 EE Part financed by the European Union ie EfficienS 4 Le vail Bee C A Baltic Sea Region E I l ca Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea Kuradimuna and more coastal sea was represented by Karbimadal Muuga bay To cover seasonality one measurement period was settled in August September and another in October Nov
21. L ee fe EfficienSea Baltic Sea Region Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea Title Efficient Safe and Sustainable Traffic at Sea Acronym EfficienSea Document No D WP4 X X Document Access Public Development of sea state registration and analysis technologies Contract No 013 ae oes re Baltic Sea Region Programme 2007 2013 Part financed by the European Union European Regional Development Fund and European Neighbourhood and Partnership Instrument Part financed 1 by the European Union efficiensea org 1 P eh EfficienSea Baltic Sea Region Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea DOCUMENT STATUS Authors Estonian Maritime Administration Cybernetica AS Cybernetica AS Tiit Pikpoom Cybernetica AS Reviewers Part financed 2 by the European Union efficiensea org 2 e a r AA eo AA eer ira a na Y Baltic Sea Region EfficienSea eo Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea Annotation This document describes the Wave Height and Period Analysis Software solution called WHAPAS that is intended for shore side calculation of significant wave height in marine area where navigational buoys equipped with TelFiCon GSM GPRS telematics units implementing 3 axial acceleration measurement are deployed Explanation of t
22. PONEN ccccceeeeceeeeeeeeeeeeeseeaeeeeeesaeeeeeeeaes 14 Ded MUTA PO DCN A UIO IN aragee ccaapuccs tn ondeecte a aacwtaaadges tsabasedine edoeconavancuunaesovcsiasoneuneedeecennonecuee 14 3 Calculation of Significant Wave HeIGNt cccscccssscesssccessecesseceseesesseeesseeeesseeesaeens 15 31 Calculation FAI OP VERMA cas cincaboecsccarseses bec Ganer n a Ea an E 15 3 2 Verification 61 0 gt eee ne re rn E 17 APPENDIX 1 Reference measurements for WHAPAS software calibration 19 1 1 General approach tO OCEAN WAVES ccccccessccessecesssecessecesseecessecesseceeseesesseeessteeesesenstens 20 1 2 Depth dependence Of wave ParaMEeelS c ccccscccesscccsseccsssecesecesssecessecessecesseeesseeeens 22 1 3 Dependence of wave parameters from morphometry of the coastline 23 1 4 Shape of the wave shape and particularly wave shape in the Baltic Sea 25 1 5 Wave measurements in vicinity of navigational buoys at Karbimadal and Oe eae e AEN E N tcadina tarde EEEE EEE AEE EEEE 26 1 6 Measurement equipment ssccencscevsesaversveseetusecreecnsverisaevsebaveninesseieacsemnieriianaeerennen eee 28 1 7 Conversion of measured sub surface pressure into surface elevation spectra 32 efficiensea org 5 ea ee 5 the European Union r oe AS EfficienSea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea 1 8 Comparison of wave heights measured with two different
23. Resulting additional communication efficiensea org 7 ea ne 7 the European Union r EfficienSea Baltic Sea Region 7 Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea of yt Ve E 27 e e perry and energy costs are expected to remain insignificant in comparison with benefits from near real time in situ wave height measurement Abbreviations used Abbreviation Explanation AIS Universal Automatic Identification System used for marine navigation safety related ship to ship ship to shore and shore to ship digital communications based on the standard ITU R M 1371 a QJ AtoN Aid to Navigation refers either to a marine visual aid to navigation site in general or to a set of electro optical systems of an AtoN outstation for provision of visual light signalling cron Time based task activation application in Unix like operating systems DTD Document Type Definition description of an XML document FFT Fast Fourier Transform an algorithm for calculation of spectra GPRS General Packet Radio Service a GSM cellular network service for TCP IP based data communications GSM Global System for Mobile Communication a digital radio communication network standard 900 1800 MHz in Europe HTTP Hypertext Transfer Protocol is used for serving of digital content to standard web browsers based on RFC 1945 IPv4 Internet Protocol version 4 the current digital data exchan
24. Victor Raudsepp Urmas Kouts Tarmo 2008 Wind wave measurements and modeling in Kiidema Bay Estonian Archipelago Sea Journal of Marine Systems S30 S40 Alari Victor Raudsepp Urmas K uts Tarmo Erm Ants Vahter Kaimo 2009 On the validation of SWAN a third generation spectral wave model in Estonian coastal waters In BSSC 2009 7th Baltic Sea Science Congress 2009 Abstract Book August 17 21 2009 Tallinn Estonia Tallinn Tallinn Tallinn University of Technology 2009 183 183 Alari Victor Raudsepp Urmas 2010 Depth induced breaking of wind generated surface gravity waves in Estonian coastal waters Boreal Environment Research 15 295 300 Alari Victor Raudsepp Urmas Erm Ants 2010b Comparison of ADV Measured Near Bed Orbital Speed and Latter Derived From Wave Gauge Measurements at Intermediate Water Depths 4th IEES OES Baltic Symposium Riga Latvia August 25 27 2010 IEEE Inst Electrical Electronics Engineers Inc 2010 1 7 Alari Victor 2007 Modeling of wave field included fast ferry wakes In Study of Naissaar Harbour Area Report Series of Marine Systems Institute at Tallinn University of Technology C H Tsai M C Huang F J Young Y C Lin and H W Li On the recovery of surface wave by pressure transfer function Ocean Eng vol 32 pp 1247 1259 2005 Jonsson A Broman B Rahm L 2002 Variations in the Baltic Sea wave fields Ocean Engineering 30 107 126 R
25. a Region Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea 3 6 5 1 E9263 1 enclosure ABS 3 6 6 Ingress Protection 3 6 6 1 E9263 1 enclosure IP64 EN 60529 3 6 6 2 GSM GPS antenna IP67 EN 60529 3 6 7 GSM GPS antenna TecSys AU 3S GSM size excluding cables and cable entry hood 64 5mm D x 14mm H Cable length 5m for antenna with magnetic mount optional 1 2m or 2m through hole mount Weight 0 15 kg with magnetic mount and 2m cables 3 6 8 Description of E9263 1 mounting hole pattern 4x 4mm holes in the corners of a E9263 1 box measuring 110x90 mm Figure 3 using these holes for fixing needs opening of cover of E9263 1 3 6 9 Description of antenna mounting magnetic mount required area 80 x 80 mm hole pattern for through hole antenna one 12 5 mm hole optimal thickness of structure 5 mm 3 7 ENVIRONMENTAL CONDITIONS OF USE 3 7 1 The electronic module E9263 1 is designed for application in the following environmental conditions 3 7 1 1 Temperature of the environment between 25 C to 70 C 3 7 1 2 Relative humidity of the air of 90 at 30 C 3 7 2 Ingress protection class of the E9263 1 module is IP 64 3 7 3 Vibration tolerance limits up to 5 g 10 Hz 2 KHz EN 60945 8 7 EN 61068 2 6 3 7 4 Shock tolerance limits up to 6 shocks of up to 10 g in any of 3 axes EN 61068 2 27 3 7 5 EMC immunity within the limits of EN 60945 p 10 EN 61 000 4 2 EN 61000 4 3 EN 61000 4 4 EN 6
26. apshot of in situ wave package during 10 minute long time sequence measured with pressure sensor high variability in wave heights during that short time period could be easily observed from the graph 1 5 Wave measurements in vicinity of navigational buoys at Karbimadal and Kuradimuna In summer and autumn 2010 two wave measurement sessions were carried out at the Kuradimuna Bank in the Gulf of Finland and at the Karbimadal Bank in the Muuga Bay Purpose of measurements was to obtain time series of basic wave parameters as typical for summer and autumn wind conditions in order to compare wave data with these obtained experimentally from navigational buoys Measurement sites were chosen so that these were in close vicinity of efficiensea org 26 e part financed26 the European Union r M EfficienSea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea navigation buoy reporting wave parameters for same measurement periods Two measurement sites should also represent typical conditions inside the coastal bay Karbimadal in the Muuga bay and more open sea conditions as recorded in Kuradimuna Two wave recorders LM2 were used Fig 7 the working principle of which is based on measurement of pressure at fixed position of the probe with absolute pressure sensor Keller Ltd Instrument is installed 5 8m below sea surface Fig 8 and measured pressure is converted to height of water column with 4Hz sampling rate wh
27. art financed by the European Union See EfficienSes Baltic Sea Region x i Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea C Analog input Measurement range 0 3 3V 10 bit ADC Coaxial connectors GPS SMA Female connector to active GPS antenna lasm FME Male connector to GSM 900 1800 antenna GSM 3 9 CONTACT INFORMATION OF THE SUPPLIER Cybernetica AS Department of Navigation Systems Akadeemia tee 21 12618 Tallinn ESTONIA Mr Aivar Usk head of Department of Navigation Systems aivar usk cyber ee GSM 372 51 31021 Phone 372 639 7991 direct 372 639 7978 Fax 372 639 7992 http www cyber ee info cyber ee http www ekta ee ekta ekta ee Part financed by efficiensea org 55 Fa the European Union
28. asured wave parameters were conditioned same way for each of measurement location and period stored in ASCII files and given to Cybernetica AS for set up of calculation algorithm for waves from acceleration sensor output Significant height m a Peak period s Max height m Figure 11 Example of wave measurement time series registered in Kuradimuna October November 2010 Wave parameters are derived form pressure measurements using method described in Chapter 2 4 Graphs from the top significant wave height wave peak period and maximum wave height Part financed by efficiensea org 34 Fa the European Union pi EfficienSea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea 59 727 59 697 59 667 59 637 Latitude N 59 607 59 5 7 59 547 59 517 24 783 A BLY sore wor oS NM4E7 89 70 a Karbimadal 3 LFI 10s7M ajut kustut _ N53 24 813 24 843 24 873 24 903 24 933 24 963 24 993 25 023 Longitude E Figure 12 Location of navigation buoys on board of those waves were measurements using acceleration sensor performed and data compared with pressure based wave measurements with red triangles Part financed by efficiensea org 35 Ea the European Union in EfficiensS 4 SS cie S Baltic Sea Region E I l ca Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea 1 8 Comparison of wave heights measured wit
29. ata storage electronics was designed and built by PTR Group OU already in late 1990 s Instrument principally records pressure values at given rate of 2 4 or 8Hz In most cases measurement rate is 4Hz which should be enough to catch waves with shortest periodicity of 2 3s in the coastal zone In open sea wave period goes to 4 5s and in case of extreme storms even to 6 7 seconds From that point start wakes generated by fast going ships and wave periods can be from 8 15s This instrument is previously used both for measurement of natural and ship generated waves all over the Estonian coast as well as in the open sea Results of measurements are published in a number of peer reviewed papers also a comparison with other wave recording instruments SeaBird Aanderaa Data Instruments etc has been made in the past and sometimes parallel measurements are also repeated today Pressure sensor has been built in temperature compensation Pressure data together with water temperatures are written on SD memory cards Downloaded pressures are used then for calculation of wave parameters using method described in Chapter 2 4 Pa rt financed g efficiensea org 28 by the European Union Ce Baltic Sea Region Programme 2007 2013 No cable required runs on 4 D cells Logs pressure and temperature Records up to 30 million lines on a 128 Mb MMC memory card Dimensions 100 mm by 470 mm Weight 4 kg in air Programmable sampling frequ
30. ched to the main anchor The connecting rope was left floating to make it easier to find and recover the buoy station if the mark buoy should get lost Both wave recorders were placed west of the aforementioned banks Fig 9 in the vicinity of the west navigational buoys that were equipped with acceleration sensors The bank name and necessary information was marked on the buoy stations should other persons find them and to avoid mix up of data series Launching and recovering of mooring stations was done with the research vessel SALME Marine Systems Institute at Tallinn University of Technology Coordinates are given in Table 1 Table 1 Coordinates of mooring stations where wave measurements were performed in summer autumn 2010 Karbimadal 20m 59 33 284 24 56 758 i 31 08 Sivan Kuradimuna 20m 59 41 946 24 52 882 Karbimadal 20m 59 33 298 24 56 733 20 10 17 11 2010 Kuradimuna 20m 59 41 862 24 52 807 efficiensea org 27 Pa rt financed 7 by the European Union 90 eee Effi a nS ff ed Cie 2 Baltic Sea Region i ca Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea 1 6 Measurement equipment Instrument for wave measurements we used in this case is wave pressure recorder LM2 developed and built by Estonian local company PTR Group OU Measurement sensor is piezoelectric pressure sensor by Keller Ltd Switzerland All signal processing and d
31. con E9261 Instructions for Use Cybernetica AS 9261 004 2 GPRS keskus Tarkvara arhitektuur Cybernetica AS N B76250 13 3 AIS Router a module for routing AtoN specific AIS messages M8 M12 M14 and M21 Cybernetica AS Y 399 28 4 Hydrometeorological Data Module for AIS AtoN Router Owner s Manual Cybernetica AS Y 399 44 2 System Summary 2 1 System Configuration The WHAPAS system is intended for installation either on a single institutional server or a constellation of distributed servers for operation as an autonomous back office application requiring no user intervention unless re configuration is needed The software has practically no user interface it analyzes the input data retrieved from a pre configured source locations in the local area network and places the calculation results to pre configured locations for use by other applications The WHAPAS software is hardware independent it was developed in Java SE 6 environment by Sun Microsystems and will run on all platforms supporting the corresponding runtime environments For the purpose of guaranteeing high availability it is recommended to run the core software component responsible for data analysis on a dedicated server hardware with GNU Linux compatible operating system since fast calculation of wave height from multiple sources can become resource demanding WHAPAS is supplied in a single Java Archive JAR file that contains all necessary components The
32. converted to a subsurface elevation time series units of height Then the time series is divided into five minute sections called wave packets Additionally the packets are de averaged and de trended The mean value is used in order to calculate gauge depth which is needed for the calculation of the attenuation coefficient Further on power spectral density is estimated by using the Welch method and a Hanning window is used to smooth the spectrum The obtained subsurface elevation spectra s7 are converted to surface elevation spectra S using the linear wave theory 2 s asa cosh kd coshk d z with k denoting the wave number calculated from the linear dispersion equation d water depth and 1 z elevation of the pressure gauge relative to the mean water surface negative downwards The linear dispersion equation at intermediate water depths reads Part financed by efficiensea org 32 Fa fi the European Union ie EfficiensS 4 See cie Baltic Sea Region i I l ca Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea gk tanh kd 2 where g is the acceleration due to gravity and is the angular frequency In practice the transcendental equation 2 which needs iterative solvers is replaced with a polynomial approximation to reduce calculation time From the surface elevation spectrum two important characteristics are derived significant wave height and the period corres
33. d by the centre over the air 3 5 3 Acceleration measurement within 3 g on three axes with the resolution of 0 01 g is an optional feature of a Telficon unit An acceleration measurement mission is activated by the TeVINSA centre in either continuous or periodic mode resulting in data traffic corresponding to sampling interval and the duration of data acquisition sessions as described in Table 2 3 5 4 The sampling interval data acquisition interval and data acquisition session length can be changed using the TeViINSA centre over the air in the beginning of a communications session with TelFiCon The acceleration values recorded can be made available for detailed analysis in the form of CSV files 3 5 5 A TelFiCon features built in capability for acceleration based buoy heel angle calculation with a resolution of 1 degree variable sensor output sampling times and time averaging for average angle as well as excessive and critical heel angle alarms To obtain meaningful heel angle statistics averaging times must not exceed the regular reporting interval length efficiensea org 50 Fa the European Union Part financed by ie EfficiensS 4 gs oo cienSea Baltic Sea Region I l l i Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea 3 5 6 To conduct uninterrupted communications over the GSM GPRS IP connection GSM signal level at the E9263 1 input should be 70 dB and above Use of antenna with 5m cables is
34. d depth induced breaking in water depths less than 10 m Alari Raudsepp and Kouts 2008 Alari and Raudsepp 2010 efficiensea org 22 pea part financed22 the European Union SS Baltic Sea Region EfficienSea Sama Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea 1 3 Dependence of wave parameters from morphometry of the coastline Morphometry of the coastline in certain area together with depth profile are major components forming the local wave field realization Number of other circumstances drive the wave field variability most important of those is of course wind but also currents presence of ice or algae alter the wave parameters depending on their intensity accordingly as well There can t be sorted out universal methods or algorithms giving general key to solve those local peculiarities of wave field That s the reason why if it s necessary local wave field is modeled individually in the interested area Using real bottom topography and coastline forcing wind can be both idealized to show wave field realization in extreme cases as well as real to show natural evolution of wave field and compare the model results with measurements Before using local scale model in certain sea area validation and local set up of the model with in situ measurements is an essential precondition in order to gain acceptable results As particular example from Estonian coastal sea a numerical experiment with a phase resolving mo
35. de in order to support safe navigation with wave information Still one has to be careful using wave models in sea areas with complicated morphometry as is the case for Estonian coast In open sea yes most of wave models work good but in coastal sea measurement data is definitely needed first to set up the model then validate the best results will come if data is assimilated into the model continuously As navigational buoys are installed in a number of locations along the Estonian coast and also the Open sea and most of cases into navigationally critical places an idea to use those as wave measurement platforms naturally came into use On the other hand buoys are technologically equipped with acceleration sensors for other purposes but could still be used for estimates of wave parameters There are several problems slightly different shape of the buoys their different weight etc but this didn t stop us from trying the idea At first approach effort was undertaken to estimate parameters of wave field around the certain navigation buoys and then try to find most suitable algorithm to get wave data from acceleration sensor output For that purpose two measurement campaigns were planned both using two pressure sensor based wave gauges in two different locations near the navigation buoys in Karbimadal and Kuradimuna From these two Karbimadal is a more inner location in the Muuga Bay and Kuradimuna reflects wave regime in the open Gulf of Fi
36. del COULWAVE TTU Meresiisteemide Instituut 2007 was undertaken in order to study the interaction between Naissaar harbor jetty and fast ferry wakes The results showed that the reflected wave did not propagate more than 200m from the harbor constructions In case of wind waves which are shorter and normal coastline where bottom dissipates much energy the propagation of reflected wave is even more restricted As harbour jetty is a vertical wall in water its wave reflecting features are much better than most of the coastline we can summarize that wave field is directly affected by coastline wave reflection stays inside the 200m zone As an example of the large scale alteration of wave field due to coastline consider a wave field realization in Tallinn Bay during a W storm Naissaar Island not only damps waves Fig 3 but the underwater slope at the southern tip of the island refracts waves to an extent where pure westerly waves change their direction up to 90 degrees Pa rt financed 3 efficiensea org 23 k the European Union _ OY iy i i SS baltic Sea Region EfficienSea PTY Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea Significant wave height at 2007 09 06 11 00 00 UTC 59 65 59 6 59 55 Latitude N Height m ts 59 45 TALLINN E 24 3 2435 244 2445 245 2455 246 2465 247 2475 248 Longitude E Figure 3 Significant wave height in Tallinn
37. dity then forwards valid data to a software module that analyzes the three axes and establishes a common vertical acceleration axis which is arranged upright using mathematical methods Heel angle of this derived vertical acceleration axis will change very little in time allowing to calculate the wave height and period The method used for wave height calculation can be unique for each acceleration data source buoy when prepared this way At this time WHAPAS uses only a single FFT based analysis method Once the wave height and period are calculated the corresponding values are transferred to the Results Output Software Component ROSC Acceleration data Reception of the conversion from Wave height Send the calculated wave heights to acceleration data three dimensonal to calculations the output module one dimensional Figure 3 Flow diagram of WCSC operation Similarly to the DRSC s it is also possible to operate several correspondingly configured WCSC s on separate computers on a computer network having them feeding the calculation results to a single ROSC 2 2 3 Results Output Software Component The Results Output Software Component ROSC shown as Output in Figure 1 is responsible for interpolating all wave height data received from WCSCs to a 10 minute time interval filtering the data and formatting the output values in accordance with the input specification of the Hydrometeorological Data Module of
38. e Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea when the module enters the transmission power mode 5 for up to one second every time it has acquired a full buffer 252 Bytes of measurement samples 63 samples from each axis Example Average current consumption in continuous buffered acceleration measurement mode with 50 ms sampling interval within excellent GSM signal coverage 60 mA 12 VDC 40 mA 20 VDC resulting in daily consumption of 1 44 A 0 96 A 3 4 3 Reverse polarity circuit protection implemented 3 4 4 Power supply terminations screw terminals for up to 1 mm wires and 3mm blade screwdriver 3 5 CONTROL AND COMMUNICATION SPECIFICATIONS 3 5 1 When powered up a TelFiCon unit attempts to establish a connection over GSM GPRS IP network with the control and monitoring centre server running at Cybernetica AS Estonia to report its current status and position and to download optional mission parameters Settings necessary to enter the IP network of a specific service provider need to be pre configured using dedicated maintenance software before deploying the unit 3 5 2 In case of a typical application scenario a TelFiCon monitors status and position of an aid to navigation outstation using a proprietary RS485 based local area network to connect to flashers and power supplies of ekta brand manufactured by Cybernetica AS reporting to TeViINSA control and monitoring centre at the intervals configure
39. e in the Baltic Sea Considering the shape of wave spectrum the SWAN wave model can be used to accurately reproduce the shape of the waves Realization of certain wave spectrum is the sum of sine and Pa rt financed 5 efficiensea org 25 ea 5 the European Union a EfficiensS 4 g cie 2 Baltic Sea Region i Ca Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea cosine elementary waves with alternating phases and amplitudes the actual wave field infrequently resolve a pure elementary wave Waves come in groups as can be seen on Fig 6 where 10 minute long time series of in situ wave height is presented this is frequently the period for which wave information is generalized In fact no solid physical mechanism behind wave group formation exists yet alone for their spatio temporal prediction Fig 6 gives an idea of complexity of actual wave situation based on which some generalized picture is actually created Besides the wave groupings waves also have a pronounced crest trough asymmetry This is best seen at time moments of 180s and 285s In the first case the crest height is 1 9m and the trough depth is 2 6m In the second case the crest height is 1 2m and the trough depth is 2 3m Almost all the asymmetries resemble holes in the sea asymmetries which in certain cases could pose a particular threat for navigation Amplitude m 0 100 200 300 400 500 600 Time s Figure 6 Sn
40. ember which was not 100 successful as during late summer measurement period we observed the most intensive storm event at the very beginning of the period already Nevertheless when pressure based probe data are complete and continuous for both measurement periods then navigation buoy data have significant breaks in mainly because of communication failures As method of wave measurement with acceleration sensors now means transfer of full package of raw acceleration data from buoy into server and processing in server then obviously dependence from stability of communication line is high By analyzing wave height measurement results with two different methods one can observe that average differences in wave heights between accelerometer s data and pressure based wave probe data are low in some cases even very low being lower than 10cm for most of the time series and reaching 20 cm only in some cases Still there are some problems and these are the cases of high wave height because of communication failure there are several cases when storm event was observed with differing wave heights in Kuradimuna and Karbimadal but no comparison data from navigation buoys First storm at the very beginning was well captured in that sense but measurement period in October November was not very successful As a result we have comparably few comparison data for higher wave heights which in turn is not good as data from navigation buoys is dedicated for the na
41. ency Uses Keller PA 10 absolute pressure sensor efficiensea org 29 EfficienSea Efficient Safe and Sustainable Traffic at Sea Ranges Pressure 0 1 bar 0 10 m water column Temperature 0 50 C Sampling frequency 25 per second up tol per hour Other data PC interface USB Sampling starts with magnetic key Figure 7 Wave pressure recorder LM2 and its main technical features Pa rt fing ged by the European Union mers EfficienSea r F 4 ee Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea Installation of wave recorder is very important as this should be fixed under water to measure as precise as possible height of water column above the sensor For that purpose mooring scheme presented on Fig 8 is used In order to catch waves with period less than 4s hydraulic effect of wave decay and in the Baltic Sea coastal zone they are usually below 4s the instrument should be installed not deeper than 10m the closer to the surface the better Still it has to be taken into account that waves could be as high as 4 5m and fine tuning of measurement depth is essential and lays in best case between 6 8m Sometimes even shallower in this case it s coastal zone and known that wave height does not exceed 2 3m so the instrument can even be installed at 3 5m below surface As an example Fig 10 shows depth of the wave recorder during the entire second measurement period in Karbimada
42. esults however need further investigation to find out the reason for such a big difference between two data series in this quite prominent storm case During another major storm event on Nov 10 data transfer from navigation buoys was unfortunately interrupted and we don t have comparison data with reference measurements for this event Looking at dissipation phase of wave height time series one can find out that in this part wave dynamics is well captured by both methods Ref Hmax Ref Hsig Hsig i i i A i AANA AN A 20 10 2010 22 10 2010 23 10 2010 24 10 2010 26 10 2010 27 10 2010 29 10 2010 30 10 2010 01 11 10 02 11 10 02 11 10 03 11 10 05 11 10 06 11 10 07 11 10 09 11 10 10 11 10 12 11 10 16 00 02 20 12 40 23 00 09 20 19 40 06 00 16 20 01 00 EL 11 20 EL 04 40EL 03 00 PL 01 20EL 11 40 E 10 00PL 08 20EL 06 40 PL 05 00 EL Figure 20 Significant wave height as measured by acceleration sensor on navigation buoy NM186 blue and pressure sensor based probe red in Karbimadal second measurement period Yellow line shows maximum wave height recorded by pressure probe Part financed by efficiensea org 42 Fa the European Union eon EfficienS 4 n cie 2 Baltic Sea Region i l ca Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea _ E J lt a 1 co gt 1 5 20 10 2010 24 10 2010 28 10 2010 1 11 2010 5 11 2010 9 11 2010 13 11 2010 NM159 NM157 Figure 21
43. esults of reference measurement were used to determine buoy specific correction factors in an incremental fitting process Next the factors producing smallest differences compared to reference data were applied at the analysis of the same set of buoy acceleration data at the input of WHAPAS and the final deviations from reference values were noted Due to the different measurement and averaging methods utilized by the reference sensor and the TelFiCon sensor non synchronized sampling as well as a positioning difference of about 20m certain differences in results were expected and are not necessarily presenting a measurement uncertainty Differences between the reference values and best fit values calculated by WHAPAS with application of correction factors derived from the same experiment are presented in Table 1 Pa rt financed 7 efficiensea org 17 k the European Union Ka eee EfficienSea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea Table 1 Differences between wave height reference measurement and WHAPAS results Percentage of Maximum difference in calculated significant wave height calculation results m ane maximum Range 0 0 m to 2 0 m Range 2 25 m to 5 0 m ifference 21794 reference points 401 reference points 68 27 0 29 0 63 90 00 0 37 0 78 95 00 0 41 0 86 95 45 0 41 0 87 99 73 0 53 1 10 Graphical distribution of the differences of the calculated
44. fic at Sea EfficienSea project that was part of the Baltic Sea Region Programme 2007 2013 1 2 Background Measurement of the significant wave height on the waterways with following timely provision of this information to the mariners is an important aspect of marine navigation safety while cost efficient implementation of it is not an easy task Dedicated wave height measurement equipment is expensive to procure and maintain while emerging satellite based methods are not expected to provide reasonable resolution neither in time nor in coastal area coverage Marine weather stations are often deployed in locations where actual Open sea wave parameters are influenced either by nearby structures or shallow water depth Although the measurement of wave height using accelerometric sensors installed onboard regular navigational buoys results in a significant trade off between precision of the results and additional power consumption of the remote system when compared to dedicated wave following buoys it can provide usable estimation of sea states in near real time when data processing is performed at the server side The main difference of the wave height measurement enabled by the TeViNSA WHAPAS solution is utilisation of the existing infrastructure deployed for remote monitoring of visual aids to navigation and AIS message broadcasting with value adding functionality without the need for additional investments into the existing hardware infrastructure
45. ge protocol with 32 bit addressing of hosts on the Internet JAR Java Archive a file format for compressing of several Java files into a single file Java An object oriented high level computer programming language developed by Sun Microsystems VM Java Virtual Machine runtime environment for executing software applications created using Java SI The Marine Systems Institute of the Tallinn University of Technology SQL Structured Query Language standard format for performing data queries from relational databases Transmission Control Protocol Internet Protocol for reliable connection less digital packet data transmission used in the Internet based on RFC 793 Telematics Field Controller a GSM GPRS GPS based AtoN telematics hardware module developed and manufactured by Cybernetica AS TCP IP TelFiCon TeViNSA Telematics for Visual Navigation Situational Awareness a set of software and hardware components developed by Cybernetica AS for remote control and monitoring of remote AtoN site systems measurement and broadcasting over AIS of relevant e Navigation data Part financed 8 by the European Union efficiensea org 8 r se on 10 oa EfficiensS Ze SSS O cienSea Baltic Sea Region i n Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea Abbreviation Explanation WHAPAS Wave Height And Period Analysis Software 1 4 References 1 Telematics Controller Telfi
46. h of the sea at the locations used for comparisons is quite similar shape of the buoys does vary in some extent but not that much 4 5 3 5 Ref Hmax Ref Hsig Hsig 2 5 Wave height m k s WN A EANA RN N Y 0 5 ty 4 UG o 01 09 10 02 09 10 03 09 10 05 09 10 06 09 10 07 09 10 09 09 10 10 09 10 11 09 10 13 09 2010 14 09 2010 15 09 2010 17 09 2010 18 09 2010 19 09 2010 21 09 2010 22 09 2010 05 20 EL 01 20 PL 09 20 PL 05 220 E 01 20 PL 09 20 PL 05 20 EL 01 20 PL 09 20 PL 5 20 13 20 21 20 05 20 13 20 21 20 05 20 3 20 Figure 13 Significant wave height as measured by acceleration sensor on navigation buoy NM186 blue and pressure sensor based probe red in Karbimadal first measurement period Yellow line shows maximum wave height recorded by pressure probe 1 8 1 Wave heights comparison for first measurement period 1 23 09 2011 Analyzing the measurements of the first measurement period one can conclude that significant wave height calculated from acceleration sensor data and pressure probe fit with each other quite Part financed by efficiensea org 36 Fa the European Union fib EfficienSea Programme 2007 2013 well especially for Karbimadal In fact measurement period was quite interesting as the main intention with late summer measurement period was to catch wave dynamics of a calm season in fact we got a severe NW NNW storm with average wind speeds over 20m s Fig 14 already at the ver
47. h other At some time instances the accelerometer data from navigation buoys overestimates pressure based measurements and sometimes underestimates Due to the problems in data transfer during the strongest storms we can t say how well the navigational buoy data measured Not going into depth of wave height calculation algorithm one can say that the growth and dissipation phases during the two highest wave events around Nov 4 and 10 were well reproduced by accelerometer data at Kuradimuna which allows us to assume that the wave event maximums were also well determined by this measurement method Failure of data transmission during major wave events is of course a problem as we didn t get very valuable comparison data for extreme wave situations which in fact are rare but very important from navigational point of view Part financed by efficiensea org 40 Fa fi the European Union Z EE pan EfficienSea Baltic Sea Region l Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea wind direction a N amp D Q WY D 2 S M hik E ak E A A l M T A E O O Ww o r 0 I I I I I I 19 10 2010 24 10 2010 29 10 2010 3 11 2010 8 11 2010 13 11 2010 18 11 2010 wind speed wind direction Figure 18 Wind speed and direction during the second measurement period Ref Hmax Ref Hsig Hsig yV y AA AJ Wa N W 20 10 2010 22 10 2010 23 10 2010 24 10 2010 26 10 2010
48. h two different methods For comparison of wave heights obtained from navigation buoys and those measured with special probe with pressure sensor show generally good agreement between those two Agreement is best in case of closest buoy and reference measurement site which is natural as obviously wave field can t be homogeneous even over several square miles in the region because of morphologic features reflections diffraction effects varying depth profile along the coast etc Algorithm used to calculate wave parameters from acceleration data on navigational buoys called WHAPAS Wave Height An d Period Analysis Software is rugged self contained software module running on data acquisition servers Acceleration data as raw time series are transmitted over some time sequence and then analyzed WHAPAS User Manual Calculation method passed several simplifications and at the send it is simple straightforward formula containing two variables measured on board navigational buoy acceleration and wave period Still an important correction factor naturally tied into calculation scheme is the so called buoy parameter depending on the shape of the buoy length of the chain etc so quite individual in every case It must be cleared that WHAPAS analyses only significant wave height not the maximal one as inertia of the navigational buoy is quite remarkable and therefore max wave heights are hard to estimate In our comparison experiment at least dept
49. he operating principles of the software components as well as results of testing conducted for buoy calibration and wave height calculation algorithm verification are provided Limitation of Liability and Copyright Notice efficiensea org 3 pea ne 3 the European Union ie EfficienS 4 ee cie a Baltic Sea Region I L ca Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea This User Manual is intended for providing guidelines for using the product that it was supplied with and does not represent a commitment on the part of the manufacturer for performance of any similar past or future products The information in this document is subject to change without prior notice in order to improve product reliability functionality or design While reasonable efforts have been made to ensure the accuracy of this document the manufacturer and distributors assume no liability resulting from errors or omissions in this Manual In no event will the manufacturer be liable for direct indirect special incidental or consequential damages arising out of the use or inability to use the product or documentation This document contains proprietary information protected by copyright that is to be used only by persons to whom the document has been legally supplied in the course of obtaining the product that is described within All rights are reserved any unauthorized copying disclosure distribution printing translation or u
50. he rest of WHAPAS components and is only activated manually to update the WHAPAS settings database when such need emerges Such setup is optimal due to the fact that all the changes at TeViINSA database affecting WHAPAS operation are performed manually anyway Nevertheless when fully automated activation of SSSC with a pre configured time interval is considered necessary such arrangement can be made by the use of external scripts like the cron service of Unix like operating systems 2 3 WHAPAS Operation WHAPAS has no user interface it is started up on the server hosting the software either by an automated start up script run at the operating system start up in case of regular use or in manual mode for temporary use by entering WHAPAS at the command prompt of the GNU Linux operational system console To request the help information on command line parameter options the operator must enter at the command prompt WHAPAS h Configuration settings of WHAPAS are maintained in an XML file that is not accessible for direct editing changes can be implemented either by logging into the CMSC terminal or by copying the settings from TeViNSA database efficiensea org 14 Ee eda the European Union e One s he aha _ a WZ ce itic Sea Region EfficienSea d Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea A detailed manual with all commands configuration options and XML configuration file contents is prov
51. iability and not caused by measurement methodology Part financed by efficiensea org 38 Fa the European Union eh EfficienSea Baltic Sea Region Programme 2007 2013 In case of Kuradimuna the comparison results are not so good and that is the case for both navigation buoys NM157 and NM159 During storm difference of significant wave height reaches Im Fig 17 to remember wave height itself was up to 2 8m during that event Still looking at comparison graph of two datasets Fig 15 one can observe that navigation buoy has some inertia starting later show higher waves and decay of waves comes a bit later from those major deviations That is quite reasonable as navigation buoys are heavy together with chains maybe several tons and have for sure inertial effect if moving with waves Otherwise in Kuradimuna case comparison of buoy and reference dataset difference show quite similar pattern in case of both navigation buoys which show that wave field in Kuradimuna is comparably homogeneous in space It should also be noted that in some time moments wave height from navigation buoys fails for some period and before failure spikes of wave height difference in reference measurements could be observed Reason for that can t be estimated by using within current dataset because of a problem with calculation software or feature coming already from acceleration sensor 0 8 aai raa ARLAN h ol Pieta las OE 01 09 20
52. ics the Baltic Sea wave field is characterized by very complex nature much more complex than in the ocean for example This stems for multiple factors The Baltic Sea is divided into number of sub basins Gulf of Finland and Riga Bothnian Bay Baltic Proper etc Each one of these sub basins has its own distinctive wave regime J nsson 2002 A pronounced seasonal variability also exists where waves are higher in autumn and winter and lower in spring and summer J nsson 2002 The wind regime is frequently anisotropic especially in the Baltic Proper thus giving rise to predominated wave propagation directions also Soomere 2003 In efficiensea org 20 pea part financed2O the European Union Aco Effi a nS LZ ER cie Baltic Sea Region i Ca Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea wintertime nearly half of the Baltic Sea is commonly ice covered in hard winters even up to 85 Presence of ice of course modifies again wave field remarkably As an example of wave fields in the Baltic Sea two situations are presented on Fig 1 and 2 The first one represents the average significant wave height integrated over all months and years during the period 1970 2007 These results are presented by R met and Soomere 2010 Largest average significant wave height is found at the Baltic Proper where it 1s up to Im Contrary to average situation in the windstorm Gudrun which attacked the Baltic
53. ided to system administrators 3 Calculation of Significant Wave Height 3 1 Calculation Algorithm Calculation of significant wave height performed by WHAPAS is based on the assumption that the analysed waveform is a good approximation of a sinusoidal wave This allows calculating the amplitude of the waveform using the following formula x Xsin 2r ft 1 where t Time instance Frequency of oscillation x Peak amplitude of oscillation x Oscillating variable at the time instance t Time derivative of this formula provides velocity of the level displacement v Z 2nf Xcos 2nft 2 Since the significant wave height is described by the wave s peak to peak amplitude crest to through double extent of the amplitude provides the actual displacement D 28 3 where D Displacement of the water level Inserting the result of formula 3 into formula 2 results in the following v wf Dcos 2nft 4 Time derivative of formula 4 provides instantaneous acceleration dy ae 2n f Dsin 2rft 5 where a Instantaneous acceleration efficiensea org 15 Part financed 5 by the European Union E rs ee EfficienSea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea The components before the sin in formula 5 present the amplitude of the acceleration since we have no need to monitor the changes of the acceleration in time the following simplification can be
54. ile water temperature variations are automatically compensated by sensor electronics All data is recorded in internal memory which is SD type card Pressure sensor based measurements of wave parameters are used primarily for validation of wave calculation algorithm wave height data originated from the acceleration sensor of the navigational buoys Wave measurements were made during two periods 31 08 30 09 2010 and 20 10 17 11 2010 first one representing summer wind conditions and second autumn Limiting factor for the length of measurement period here was the memory capacity as measurements were performed in 4Hz regime 2 Hz mode would prolong the measurement period about twice In order to get best possible data quality we went for denser recording rate In other words having the sampling frequency four times per second the endurance limit for one sampling session is approximately three weeks The depth was 20 meters at both sites the wave recorders were mounted five meters below the water line Wave recorder was kept at the given level in the water column with a float but as sea level changes then the depth of the instrument also wasn t constant this feature was filtered during the data processing A mark buoy was added to simplify the recovery of the buoy stations Fig 8 In order to ensure an unchangeable position of the buoy stations in difficult sea conditions what both measurement sites actually are an extra anchor was atta
55. l and this lies well inside 0 8m Parts of variability are sea level changes as well as changes in air pressure So we can say that this type of mooring shown in Fig 8 well fixes instrument under water During data processing low frequency water level changes are filtered out and the important thing is that there can be no sudden fluctuations of the instrument depth which may show instable mooring This instrument has proved itself well in the past most important raw data for wave calculation is available and if needed several different methods of calculation could be used in our case still the method described in Chapter 2 4 Mark buoy Float Sm K Pressure sensor 20m Additional anchor Main anchor K Figure 8 Scheme of the mooring at the wave measurement stations in Karbimadal and Kuradimuna efficiensea org 30 Fa the European Union Part financed by 7 on ee z ee eee 59 727 59 697 59 667 59 637 Latitude N 59 607 99 577 99 517 Baltic Sea Region Programme 2007 2013 pi EfficienSea Efficient Safe and Sustainable Traffic at Sea aw 5 9 E 1997 tm 89 70 Karoimadal Q 3 LFI 10s7M ajut kustut _ A i LX D T a 24 783 24 813 24 843 24 873 24 903 24 933 24 963 24 993 25 023 Longitude E Figure 9 Overview of Kuradimuna and Karbimadal where wave measurements with wave recorder LM2 were performed with red triangles marking mooring sta
56. met A Soomere T 2010 The wave climate and its seasonal variability in the northeastern Baltic Sea Estonian Journal of Earth Sciences 59 1 100 113 Soomere T 2003 Anisotropy of wind and wave regimes in the Baltic Proper J Sea Res 49 305 316 efficiensea org 45 Fa the European Union Part financed by ESS EfficienSes Baltic Sea Region x i Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea APPENDIX 2 Different buoy types equipped with 3D acceleration sensors Estonian Maritime Administration using 4 new buoy hull types SJP AJP VJP and VJP2 for multi seasonal floating aids to navigation Simultaneous field experiments for calibration measurements with pressure sensor were made in vicinity of buoy type SJP up till now Hull weight 22t 25t OBE with total weight with 32 mm chain Ice buoy SJP Ice buoy AJP Ice buoy VJP Ice buoy VJP2 ivieies srs sim Part financed by efficiensea org 46 Fa the European Union ian Efficien se SE cienSea Baltic Sea Region a I l a Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea APPENDIX 3 TelFiCon E9263 1 product data and user manual 3 1 SCOPE 3 1 1 This document is intended for provision of guidelines for installation and use of the Telematics Field Controller TelFiCon E9263 1 set Technical information is presented only to the extent necessary for application of the set
57. n calculated results for calibration of a buoy the correction factors can be derived by comparing resulting two data sets When use of reference wave height data is enabled by the settings such data file at a pre set location is processed to Wave heights Reception of the processing and wave heights combining with reference data Wave heights sending to the database Import the reference Wave heights wave heights output to file Wave heights output to AIS router interpolate the wave height values for obtaining a data set suitable for direct comparison with the wave height values calculated by WHAPAS based on received buoy accelerations Such reference values are not corrected or filtered the results are recorded in accordance with the current WHAPAS settings Individual wave Inperpolation with height adjustments Filtering the 10 minute intervals with pre defined wave heights values 2 2 4 Configuration Management Software Component The Configuration Management Software Component CMSC shown as Configuration in Figure 1 is responsible for WHAPAS configuration and management of configuration settings In addition it is used for reading the initial configuration settings from efficiensea org 13 Rea el the European Figure 4 Flow diagram of ROSC operation Union Figure 5 Operations Inside the wave height processing module _ WG B Itic Sea Region EfficienSea d Programme 2007 2013 Efficient Safe
58. n of statistically sufficient amount of reference points over the range of wave heights and deriving the sufficient amount of wave height range dependent correction factors from the comparative analysis of the results of both measurements to bring the calculation results up to acceptable wave height estimation uncertainty WHAPAS settings database accepts definition of several range related correction factors per each AtoN subjected to wave height analysis In addition a capability to introduce new calculation methods and then select them for use with new AtoN objects is foreseen efficiensea org 16 pea peel the European Union E rs ee EfficienSea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea 3 2 Verification Results Tests were conducted in cooperation with the Marine Systems Institute of the Tallinn University of Technology for calibration of the algorithm for wave height calculation for specific navigational buoy and for verification of the results of server side calculation Two measurement sessions were conducted by the MSI with precision wave height measurement sensors deployed at the close vicinity of buoys No 157 Kuradimuna W and No 186 Karbimadala W in September and November 2010 resulting in 22195 reference points taken at 10 minute intervals The measurement results of the reference sensor used by the MSI are expected to provide approximately 0 05m measurement uncertainty At first the r
59. nland much better Also attempt to cover two different seasons September as late summer and October November as autumn is taken into account in case of measurement campaigns Current report gives first overview of some basic aspects of ocean waves importance in context of proposed measurement technology and applying acceleration sensors Then description of measurements campaigns performed to get set up and efficiensea org 19 Ee eaten the European Union r go EfficienSea EF nal ten tenon TIChenoCd Ea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea validation data from new technology of wave estimation Finally first evaluation to the method of wave estimation with navigation buoys applying acceleration sensors is given through comparisons with pressure wave gauge results 1 1 General approach to ocean waves In fluid dynamics wind waves or more precisely wind generated waves are surface waves that occur on the free surface of oceans seas lakes rivers and canals or even on small puddles and ponds They usually result from the wind blowing over a vast enough stretch of fluid surface Waves in the oceans can travel thousands of miles before reaching land Wind waves range in size from small ripples to huge rogue waves When directly being generated and affected by the local winds a wind wave system is called a wind sea After the wind ceases to blow wind waves are called swell Or more generally a
60. opean Union rs Baltic Sea Region EfficienSea anced Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea of yt se se N ea TER listing of acceleration data files that has relevant files added to the end once an acceleration data file is complete If a file is compliant to pre set conditions it is opened decoded and the acceleration data vectors are handed over to the Wave Height Calculation Software Component WCSC Depending on the needs dictated by the configuration of TeViINSA components WHAPAS allows installation of several DRSC modules in parallel on several hosts of a local area network with all of them feeding the decoded acceleration data to a single WCSC 2 2 2 Wave Height Calculation Software Component The Wave Height Calculation Software Component WCSC shown as Calculation in Figure 1 is responsible for calculation of an average wave height in the location of a navigational buoy from which the acceleration data received from a DRSC originate as a single task On a single server a number of WCSC modules equivalent to the number of processor cores may be run in parallel Simplified work algorithm of a WCSC is provided in Figure 4 with the algorithm described in more detail in section 3 The WCSC waits until acceleration data is received from some of the Data Retrieval Software Components Upon receiving a batch of new acceleration data WCSC checks for data integrity and vali
61. operated either on a single server or on several distributed computers e Three core software components responsible for retrieval of the input data from Te ViNSA server calculation of significant wave height and exporting of the results in relevant formats e One external software component for the management of WHAPAS settings working with a dedicated database e Two supporting software components for logging and synchronisation of WHAPAS settings with the TeViNSA database Database r Calculation Database and polling input acceleration Accal raion files file Calculation ofthe E5 Output files Wave heights Database 7 Wave reference verification E nd loadin i List file ang ioadmg interpolation etc polling and filtering eee ey Configuration synchronization from database s Command line Configuration Figure I Architecture of WHAPAS Architecture of WHAPAS is provided in Figure 1 with core component names shown in bold All three core components are fully autonomous software modules that share only the settings and log management components Data exchange between the components is arranged by the means of TCP IP IPv4 socket interfaces shown in Figure 1 with large arrows efficiensea org 10 pea ado the European Union r ah EfficienSea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea 2 2 1 Data Retrieval Software Component The Data Retrieval Sof
62. ponding to the first moment of the spectrum Significant wave height is defined as follows H 4 S df 3 The period corresponding to the first moment reads S Naf OL Fae po IS Naf 4 The term in the brackets of equation 1 is the linear pressure transfer function It is usually defined above the low frequency and below high frequency cut off respectively While the low frequency cut off is 0 05 Hz the high frequency cut off varies dynamically as does the height of the water column above the pressure sensor The high frequency cut off reads f 0282 he 5 We will illustrate the end result of conversion of subsurface pressure to surface wave time series by graphing the significant wave height maximum wave height and peak wave period during the three week measurement campaign at Kuradimuna in October November 2010 Fig 11 Although the significant wave height is very variable its average value for the three week period is 0 8m Maximum significant wave height reaches 3 7m on 9 November whereas the corresponding maximum wave height is 5 5m Interestingly even the wakes from fast ferries are clearly visible on Part financed by efficiensea org 33 F the European Union y ft EfficienSea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea the graphs as sudden peaks during low wave conditions In general the peak period grows during the growth of wave height Time series of me
63. r circuit in accordance with Table 3 starting with antenna connections SMA and FME A screwdriver with 3mm blade is recommended for making the electrical connections to screw terminals 3 8 Power up the E9263 1 Before deploying the buoy make sure that the E9263 1 has established a connection with TeViINSA remote control and monitoring centre server by contacting the Cybernetica AS telematics team 3 8 8 In order to establish the acceleration sensor positioning offset after installation of a TelFiCon on a buoy is recommended to perform transmission of acceleration measurement and heel angle data to the TeViINSA centre from the buoy maintained in Stable upright position for the duration of at least 10 minutes whenever possible Corresponding times need to be marked and the Cybernetica telematics team notified correspondingly 3 8 9 Input terminals AL1 AL2 and AN5 can be utilized for monitoring of digital and analog signals A TelFiCon needs to be properly configured in order to activate alarm message transmission to the TeViINSA centre Contact Cybernetica AS for detailed specifications when necessary Table 3 Electrical and signal connections to E9263 1 listed from bottom up i OOO Power supply GND Power supply 8 20VDC NOTE Absolute short term maximum rating is 24VDC Digital communication port for configuration and maintenance using proprietary tools RS 485 Digital input signal lines efficiensea org 54 P
64. se of this information in full or in part without prior written permission of the manufacturer is prohibited ekta TelFiCon and TeViNSA are registered trademarks of Cybernetica AS with the latter two pending at the time of publication of this document Cybernetica AS 2011 efficiensea org 4 Pee mane 4 the European Union p eek m m AA T aliit Saa fadion EfficienSea d Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea Table of Contents 1 INO PUN CU OV ee E AA E E E AS 7 L1 Scope and PUrDOSG eee eee ee ene one E E 7 L2 BACKOOUN e E peaicecutecaeaaniondeecaos datesesisdatesesisiaseeieacce 7 L39 ADDreviatons USEd e On EEE E eee 8 Lr ROOI ie 9 2 DV SE I SU E E E E EE E E 9 Zk SV SEC COMMUNE OM esie re eeaaeueeuseeys 9 2 2 WHAPAS Architecture cccccceccsssescsssseesesseesesssseesesesseeeussssessusesseesesesseneeseseeneeeas 10 2 2 1 Data Retrieval Software COMPONENL cccceececceeeeceeeeeeeeaeeeeseeseeaeseeeeeaeeaesesaeeaenaeas 11 2 2 2 Wave Height Calculation Software COMPONENL ccccecseeeeceeeeeeeeeeeeaeeeseeaeeaeeeeeess 12 2 2 3 Results Output Software Component ccccccecseceeseeeeeeeeeeaeeeeeeseeaeeeeeesaeeaesesansaeseees 12 2 2 4 Configuration Management Software COMPONEN ccccccceeceeeeeeeeeeeeeaeeeeseeaeeaeeeeaes 13 2 2 5 Log Management Software Component ccceccecceeseeeeeeeeeeeeeeeeeaeeaeseeeesaeeeseeaeeaees 14 2 2 6 Settings Synchronisation Software COM
65. sharp angles paying attention to the cables exiting the antenna with magnetic mount Observe all relevant safety rules and regulations when performing the works on aid to navigation structures Part financed by efficiensea org 53 Fa the European Union EfficienSes Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea eo I ot j0 AAA 6 Baltic Sea Region 3 8 3 In case that the TelFiCon is supplied without a metal carrier plated the top lid needs to be removed by loosening four screws in each corner using a screwdriver with Pozidriv PZ2 head Note It is strongly not recommended to open the TelFiCon enclosure in conditions of rain snowfall or other similar conditions creating a risk for any substances entering the enclosure 3 8 4 Prepare the surfaces as necessary and fix the parts firmly on host structure Do not fix the antenna with magnetic mount using materials blocking its RF signals Do not install the E9263 1 enclosure on uneven surfaces where firm contact with host structure cannot be achieved or the enclosure would remain under mechanical tension 3 8 5 Route the antenna and power cables to the inside of the equipment cabinet and fix them firmly to the structure to prevent damage from vibration as foreseen by the navigation mark design observing good practice of handling coaxial RF cables 3 8 6 Make all the connections to the E9263 1 terminals with de energized powe
66. tion coordinates efficiensea org 31 Part financed by the European Union h EfficienSea Baltic Sea Region l Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea AO e anne a H a Ve ee a rr re sot yl yoo a a a E sof 6 5 20 10 2010 0 00 25 10 2010 0 00 30 10 2010 0 00 4 11 2010 0 00 9 11 2010 0 00 14 11 2010 0 00 z lt Q m Figure 10 Graph showing the depth of the instrument during second measurement period 1 7 Conversion of measured sub surface pressure into surface elevation spectra As used in case of these measurements probe records hydrostatic pressure a conversation procedure is applied to get wave parameters out of raw data series Sub surface pressure transducers measure the instantaneous pressure that is the sum of air pressure hydrostatic pressure and wave induced dynamical pressure If air pressure and hydrostatic pressure are assumed to remain constant the dynamic pressure under water is expressed with equations derived from the linear wave theory Tsai et al 2005 That pressure is a function of three parameters the height of the pressure sensor from the seabed wave frequency and water depth At an intermediate water depth pressure decreases hyperbolically with depth therefore a sub surface attenuation coefficient has to be applied in order to get a realistic picture of wave height First the pressure time series units of pressure is
67. tware Component DRSC shown as Import in Figure 1 is responsible for retrieval of acceleration data from binary data files uploaded by TelFiCons deployed at seas and saved by the TeViINSA Core The information in those data files represents acceleration values measured at the outputs of a three axial accelerometer sensor and compressed in proprietary lossless format In addition to checking whether a new data file is available the DRSC performs integrity checking of the files relevance checking by the TelFiCon serial number in the file orientation correction of the data axes in accordance with the specifics of TelFiCon mounting onboard a particular buoy and preliminary filtration based on data file length and time stamp Simplified diagram of the DRSC is provided in Figure 2 Acceleration file loading Acceleration list Database file polling polling with one second with one second intervals intervals Least one new acceleration file File format date and device identification numbers are valid Decoding the acceleration file and sending to the wave height calculation module Figure 2 Flow diagram of DRSC operation The DRSC performs checks to discover new data files becoming available with the interval found in WHAPAS settings by default once every second Two methods are available that can be employed simultaneously checking based on TeViNSA database or based on a efficiensea org 11 Bea ena the Eur
68. vigation aid and high waves are a risk to notify about As a result of comparison we also got that accelerometers or current version of calculation algorithm better represent lower waves in case of higher than 2m waves differences with reference measurements were up to 1 5m about 50 in extreme cases As we also observed local variability pattern of wave field is important to take into account and most efficient way to do that is to implement wave modeling for this task There exist several wave models both for larger and also variable local scale as usually navigation buoys are anchored at peculiarities of seafloor usually shallows then definitely in most sensitive places like fairways anchoring places etc Occurrence of actual wave field needs detailed investigation both with modeling and experimental tools Shallows can create quite dangerous waves in one or another side depending on the wind that is described in literature as well observed by mariners Modern navigation support systems should take these risks into account and reflect these in information systems in the best possible way Another thing is of course improvement of existing wave calculation software WHAPAS also in this case modeling could largely benefit Part financed by efficiensea org 44 Fa the European Union r F Rae EfficienSea gt Baltic Sea Region Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea References Alari
69. wave heights in comparison with reference measurements conducted by the MSI is provided in Figure 6 in two ranges under and over a 2m wave height Wave heights less than two meters Wave heights more than two 25 meters 15 10 The relative number of measurements ti 0 0 05 0 10 0 15 020 0 25 0 30 0 35 0 40 045 0 50 0 55 0 60 0 65 0 70 0 75 0 80 0 85 090 0 95 100 105 1 10 1 15 120 1 20 Difference between refernce wave heights and calculated wave heights m Figure 6 Relative distribution of differences in height between the wave heights calculated by WHAPAS and wave heights obtained for the matching time periods by a reference sensor Pa rt financed 8 efficiensea org 18 k the European Union P ai EfficienSea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea APPENDIX 1 Reference measurements for WHAPAS software calibration Waves are probably the most important factors influencing navigation conditions at the sea as well as other basins usable for navigation throughout the year Waves are generated by wind and by knowing wind forecast the prognosis for wave field could be derived This works well in the open sea However in coastal sea areas number of other factors influences the realization of wave situation in certain weather conditions just to name the most important of these factors bottom topography and coastline morphology currents presence of the ice etc Generally it s so
70. y beginning This storm was exactly from that direction which creates highest waves in the study area so significant wave heights up to 1 6m in Karbimadal and 2 8m in Kuradimuna were measured while maximum wave height reached 4 5m and 5m respectively Fig 13 and 15 Storm lasted just one day and was followed by calmer period which is typical for that season wind speeds still increased step by step up to 10 12m s but direction was dominantly S the wind being from the land so the significant wave height stayed well below 0 5m during the first measurement period in Karbimadal and Im in Kuradimuna It is easily observable on Fig 15 that Kuradimuna represents more open sea conditions than Karbimadal as even wind over land can induce maximum wave heights up to 3m in this location Wind direction os D Q Q WY x 1 09 2010 4 09 2010 7 09 2010 10 09 2010 13 09 2010 16 09 2010 19 09 2010 22 09 2010 wind speed wind direction Figure 14 Wind speed and direction during the first measurement period efficiensea org 37 Fa the European Union r F 4 ee Efficient Safe and Sustainable Traffic at Sea Part financed by r A Baltic Sea Region eS EfficienSea Programme 2007 2013 Efficient Safe and Sustainable Traffic at Sea Ref Hmax Ref Hsig Wave height m wo A i 4 ail i LAL 01 09 10 02 09 10 03 09 10 05 09 10 06 09 10 07 09 10 09 09 10 10

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