Mind Peak WaveRider Spezifikationen

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102.1 Consumables 2.1.1 Logger Depending on the memory size typically the logger fills within four and a half months to two years. When full the log

1005.11.2 Electronic modules on the inside For access to the printed circuit boards the electronics unit must be dismantled. After unscrewing the th

101 To set up the console connect a serial cable to the 9-pin female plug on the electronics unit and to your terminal or PC. The terminal or termina

102Table 5.11.1. Overview of buoy commands in alphabetical order. x indicates availability for the particular buoy model. Command WR- SG DWR- MkIII

103 5.11.6 Messages As mentioned the buoy will generate messages autonomously and in response to user commands. Table 5.11.2 lists all messages that

1045.12 Logger All buoys are equipped with an internal data logger as a standard. Raw displacements measurements, wave spectra and system files gene

105 5.12.3 Retrieving logger files Before removing the flash card or even removing the power it is important that the logger is stopped. To stop the

106Table 5.12.1. Logger memory size and data capacity. Flash card size (MB) Spectra capacity (months) Displacements capacity (months)128 36 4.7 256

107 5.12.7 Event log file This file is always named HISTORY.DOC. Note that this is a human readable text file that does not contain messages. In orde

1085.13 GPS position With GPS (Global Positioning System) and HF communication the position of a drifting buoy, be it on purpose or accidentally, ca

109 5.14 Water temperature A water temperature sensor is standard on the DWR-MkIII buoy models and optional on all other buoy models. The sensor is l

112.1.3 Sacrificial anodes Aluminium sacrificial anodes slowly dissolve in sea water thus protecting the stainless steel hull through a galvanic reac

1105.15 LED flashlight Both to the well-being of seafarers and the buoy, Datawell buoys are equipped with a flash light as a standard. The colour an

111 5.16 HF communication The default way of communicating the wave data to the shore is through HF communication. Each buoy transmits at its own fre

112 Figure 5.16.1. HF whip antenna insert with LED flasher.

113 5.17 Iridium satellite communication Iridium is a satellite based cellular phone network. It is built upon a constellation of 66 low earth orbit

1145.17.4 PIN-code In order for the Iridium option to function, the SIM-card has to be in unprotected mode: a mode where the SIM-card does not requi

115 5.17.8 Buoy configuration A menu is provided to enter all buoy settings. The menu is invoked by the “settcp” console command, see figure 5.17.1.

116 d10sAT&F#~sAT+CBST=6,0,1#~sAT+CSQ#~w10:5~sATD<DIAL>#~w60CONNECT~p<USER>,<PASS>~ This is the default Iridium dial script

117 5.17.8.5 Backup scripts and addresses The backup versions of the dial script and host address settings are very important because the buoy always

118command sequences that should cater for most situations. For more detailed information please refer to the Datawell technical note library. Tab

119 5.17.10.2 Default command examples Here follow some example default command sequences Downloading of current full wave spectrum This sequence wi

122.2 Inspection 2.2.1 Mooring Bent terminals in the mooring line may indicate extreme forces. Verify with Datawell whether your mooring is suitable

120wfnme4=”S05-2006.SDT” (file with spectral data of may 2006) wflen2=26400 (length = 48 spectra of 550 bytes) wfoff2=475200 (offset = 18

121 5.17.12 Copyright The Datawell internet communication module uses the UIP TCP/IP stack. Copyright (c) 2001-2006, Adam Dunkels and the Swedish In

1225.18 Contacts and Questions For brochures, quotations and orders please contact Datawell Sales. For technical questions, support, training and ad

123 5.19 Literature [Long63] Longuet-Higgins M.S., Cartwright D.E., Smith N.D., Observation of the directional spectrum of sea waves using the motion

132.3 Service 2.3.1 WR-SG and DWR-MkIII wave motion sensor The stabilized platform vertical accelerometer consists of a fluid-filled sphere. Over the

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153 Trouble Shooting So far faultless buoy behaviour with regular maintenance only has been assumed. This chapter will deal with minor problems that

163.3.2 Magnetic compass The inclination and orientation angles of the DWR-MkIII are presented after a status request. Inclination is the angle the

173.6 LED flashlight Covering the LED flasher at the top of the HF antenna, for at least 20 secs, will set it flashing for 15 cycles (approx. 5 min.)

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194 Repair Datawell recommends you send your buoy for service and maintenance every 3 to 6 years approximately. Also if your buoy does not function c

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204.4 Serial numbers If you have any questions regarding your buoy or if you encounter problems and you wish to contact Datawell, please keep the fo

215 Reference This is the largest chapter by far. All buoy functions and buoy parts will be discussed here. To start with, the various components of

225.1 Dangers and warnings Datawell distinguishes dangers, threatening your life and warnings, threatening your equipment. Below you find a summary

235.2 Measuring waves with Datawell buoys 5.2.1 Wave height Waves at sea are the result of orbital motions of the water particles, characterized by t

245.3 Buoy parts and options This section presents an overview of the components of your wave measuring system and their location. It is subdivided

255.3.1 Mooring This subsection with figure only deals with mooring parts and naming-conventions. For the appropriate mooring layout in your local co

26 Figure 5.3.2. Constituting pieces of the mooring. Refer to section 5.8 for exact mooring design.

275.3.2 Packing frame For protection and handling the buoy should always be shipped in a packing frame. The packing frame holds the complete buoy and

28 Figure 5.3.4. Rendering of the hull components, 0.9 m diameter. (a) shows the exterior and (b) the interior.

29 Figure 5.3.5. Contents of the aluminium can in case of (a) a WR-SG and (b) a DWR-MkIII So far the contents of the aluminium can has not been d

3Contents 1 Introduction ... 72 Maintenance...

30 Figure 5.3.6. Schematic drawing of the printed circuit boards on the inside of the electronics unit and the connector block in the middle F

315.3.5 Hatchcover Two hatchcover versions exist: one with two and one with three ports. These ports are designated HF (whip antenna with LED flasher

32 Figure 5.3.9. Opening the hatchcover by using a screw in the lifting hole. 5.3.6 Antennae The antennae are also part of the modular design o

33 Figure 5.3.10.Different types of antennae: HF whip including LED flasher(a), LED flasher only whip(b), GPS wave(c), Orbcomm(d), GPS position(yello

345.4 Wave motion sensors: Accelerometers, inclinometers and compass 5.4.1 Wave height, principle of measurement The WR-SG and DWR-MkIII measure wav

35 Figure 5.4.1. Definition of the axes and signs of the DWR-MkIII motion sensors. 5.4.4 Inspection of the fluid level As mentioned in Chapter 2 Ma

36 Figure 5.4.2. Examples of the fluid level of the stabilized platform and vertical accelerometer sensor: (a) fluid level too low, (b) fluid leve

375.4.6 Calibration of the vertical accelerometer A calibrated vertical accelerometer and stabilized platform should perform within limits over 3 to

385.4.8 Magnetic compass The fluxgate compass measures the components of the earth magnetic field in three perpendicular directions referenced to th

395.4.12 Specifications For the non-directional Waverider (WR-SG) see Table 5.4.3 and for the Directional Waverider MkIII (DWR-MkIII) see Table 5.4.4

4 5.3.4 Electronics unit... 295.3.5 Hatchcover...

40Table 5.4.4. Specifications of DWR-MkIII. Parameter Value Heave Range −20-+20 m Resolution 1 cm Scale accuracy (gain error) < 0.5 % of m

415.5 Wave motion sensor: GPS 5.5.1 Wave measurement principle The GPS principle of wave measurement is explained by analogy. Apart from distance mea

425.5.6 Selective availability As mentioned the GPS system originally was and still is a military system, maintained by the United States Department

435.6 Data processing Independent of the type of sensor, the DWR-MkIII and DWR-G generate raw north, west and vertical displacements at a rate of 1.2

44The power spectral density is obtained from the Fourier coefficients 200)( HfPSD = (5.6.5a) 12/1)(22−=+=−NlHHfPSDlNllK (5.6.5b) 22/2/)(NNHfP

45Thus, one obtains: ⎟⎟⎟⎠⎞⎜⎜⎜⎝⎛vvvnvwnvnnnwwvwnwwCCCCCCCCC (5.6.12) and ⎟⎟⎟⎠⎞⎜⎜⎜⎝⎛00000vnvwnvwvQQQQ (5.6.13) Given these components a whole se

46Wave direction ),(arctan0 nvwvQQD −==θ (5.6.24) Directional spread 122 mS −= (5.6.25) Wave ellipticity or 1/K where K is the check factor

475.7 Data format Datawell uses two types of message formats: the real-time format and the message format. The Datawell real-time format refers to th

485.7.1.2 Spectrum file or full wave spectrum One level further up the cyclic data contained within 18 vectors forms one block. The cyclical data i

49Table 5.7.3. Translation equations for spectral parameters in spectrum file. Parameter Equation Remarks Frequency fn = 0.025 Hz + nΔf fn = 0.11 H

55.9.3 Mooring eye ... 815.9.4 Fender ...

50Table 5.7.4. Organization and significance of the system file data. System file word no (4 bits) System file word (12 bits) Significance 0 bits 11

515.7.1.5 Compressed wave spectrum The wave spectrum computed internally by the buoy covers 128 frequency bands and is condensed to 64 frequency ban

52Table 5.7.7 gives the formulas to restore the original parameters from the compressed representation in the 32 byte message. The 32 bytes are orga

535.7.2 Datawell message format As any message-type format the Datawell message format brings about a high degree of flexibility. In addition, the Da

545.7.2.2 CRC-4 checksum computation The CRC-4 is a cyclic redundancy check, where the 4 indicates the number of bits in the CRC checksum. Every me

55Figure 5.7.1. Listing of c-code for CRC-4 checksum computation. 5.7.2.3 Compressed heave spectrum (MsgID = 0) Table 5.7.11 explains the "Com

565.7.2.4 Spectral parameters (MsgID = 3) Table 5.7.12 explains the "Spectral parameters" message. The periods T(n,n+1) := mn/mn+1 and T(

57Table 5.7.13. Buoy information message (MsgID = 5). Byte HiNibble LoNibble 0 MsgID = 5 = 0101 CRC-4 checksum1 2 3 GPS Latitude 4 5 6 GPS Longi

58frequencies as the heave spectrum. In the even bins (0, 2, 4, …, 26), the direction is given as a 8-bit integer: *360 / 256=Dir i (5.7.17) whi

59This transformation has an additional parameter b. For very large values of b (b → ∞) the transformation becomes linear, r / rmax ≈ i / imax. For s

6 5.17.11 Error messages... 1205.17.12 Copyright...

60 The decimation is hence a list of 27 indices, k0(kmax)…k26(kmax), of the bins that are included, and since the list depends on kmax, it can be t

Table 5.7.18. Frequency bins of compressed spectra after smart decimation. fp l kmax 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

fp l kmax 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 0.225 45 17 21 25 29 33 35 37 39 41 42 43 44 45 46 47 48 49 51

fp l kmax 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 0.430 86 26 42 58 62 66 70 74 76 78 80 82 83 84 85 86 87 88 89

645.8 Mooring The correct mooring of a wave buoy is essential to measuring wave parameters according to specifications, see also section 5.2. The de

65 5.8.4 Polypropylene (PP) rope Datawell supplies synthetic fibre 12 mm multiplaited polypropylene rope, in short polypropylene (PP) rope. PP-rope i

665.8.5 Sinker For larger depths, Datawell provides in-line sinkers which avoid the polypropylene line coming afloat. The sinker consists of two ide

67 5.8.6 Floats The purpose of floats is to keep the mooring free from the seabed. Datawell provides two types of floats, a 3 Kg and a 10 Kg float. T

685.8.8 Chain coupling and swivel The Waverider buoys are fitted with a 5 Kg chain coupling attached to the mooring eye. This provides stability whe

69 5.8.9 Anodes Corrosion risks of the stainless steel AISI316 buoy hull can be prevented by applying sacrificial aluminium anodes. These anodes can

71 Introduction After having set up your Datawell wave measuring equipment by following the steps in the Installation Guide, you probably have been c

705.8.10 Standard mooring layout Mooring packages are available for each range of depth. All components are of high quality to prevent corrosion, an

71 Figure 5.8.7(a) Mooringline layout for the (Directional) Waverider.

72 Figure 5.8.7(b) Mooringline layout for the (Directional) Waverider.

73 Figure 5.8.7(c) Mooringline layout for the (Directional) Waverider.

74 Figure 5.8.7(d) Mooringline layout for the (Directional) Waverider.

75 Figure 5.8.7(e) Mooringline layout for the (Directional) Waverider.

765.8.11 Applicability of the standard mooring layout In Table 5.8.2 below, it is indicated up to what depth the standard mooring applies. If the lo

77 anchor weight, either a ship with a hoisting crane or U-frame or a ship with a removable railing should be chartered. For comfortable deployment a

785.8.14 Recovery IMPORTANT – During the recovery process the most dangerous item is the rubber cord(s). Stretching the cord(s) increases the level

79 5.8.15 Mooring hazards The phenomenon most likely to result in early failure of the mooring is galvanic corrosion between different metals in sea

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805.9 Hull and hatchcover Hull and hatchcover form a watertight compartment that provides buoyancy and houses batteries, sensors and electronics. Th

81 drag. As alternative to anti-fouling paint we supply buoys with a Cunifer10 hull. Cunifer 10 is a copper-nickel alloy which does not pit and reduc

82 Figure 5.9.1. Anti-spin triangle mounting on a Waverider buoy. 5.9.6 Handles When lifting or moving the buoy you can use the two handles welded

83 paper bag back into the plastic bag. To prevent unnecessary moisture saturation of the drying agent, close the hatch whenever the buoy is not in u

84 Figure 5.9.2. (a) Top and (b) bottom side of the hatchcover.

85 5.9.11 Radar reflectors Radar reflectors are available for the DWR MkIII, DWR-G and Waverider SG buoys with a 475 mm hatchcover. Two radar reflec

86The rechargeable cell requires a recharger. Please check the manual of the recharger for optimal use of the rechargeable cells. In short: keep the

87 Figure 5.10.1. Solar panel array with cells linked in series (A, left) or in matrix (B, right). During even reasonably short deployments, surfac

885.10.4 Battery replacement and wiring The batteries are organized, first in series of several cells and second in several series in parallel. In T

89 Figure 5.10.2. Battery numbering, wiring and grouping for a 0.9 m diameter DWR-MkIII

92 Maintenance During the life of your buoy it will require some maintenance even though it may function without error. For one thing, the buoy conta

90 Figure 5.10.3. Battery numbering, wiring and grouping for a 0.9 m diameter DWR-MkIII (including Power Storage Pack)

91 Figure 5.10.4. Battery wiring for a 0.7 m diameter DWR-MkIII. (below including Power Storage Pack)

92 Figure 5.10.5. Battery numbering, wiring and grouping for a 0.7 m diameter WR-SG (below including Power Storage Pack)

93 Figure 5.10.6. Battery numbering, wiring and grouping for a 0.9 m diameter WR-SG (below including Power Storage Pack)

94 Figure 5.10.7. Battery numbering, wiring and grouping for a 0.9 m diameter DWR-G

95 Figure 5.10.8. Battery wiring for a 0.7 m diameter DWR-G

96 Figure 5.10.9. Battery wiring for a 0.4 m diameter DWR-G

97 5.10.5 Power consumption and operational life The power consumption meter provides the remaining operational life of the buoy. Over time the readi

985.11 Electronics unit Apart from some distributed sensor electronics all electronics is concentrated in the electronics unit. The unit is located

99 Figure 5.11.1. Drawing of the connector block, in the middle, and the printed circuit boards on the inside of the electronics unit.