ProductBulletin. Vessel Tracking using HYDROpro. HYDROpro as the Tracking Controller MARINE SURVEYING & CONSTRUCTION

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1 Vessel Tracking using HYDROpro ProductBulletin January 2001 MARINE SURVEYING & CONSTRUCTION HYDROpro can be used to track vessels in applications like rock dumping, anchor tug control for rig and barge moves, dredge waste disposal, or monitoring of movement of offshore assets. This document explains the overall concepts used in HYDROpro Navigation for tracking and includes some recent examples of its implementation. HYDROpro as the Tracking Controller It is possible to track up to 99 vessels and their associated status and data such as depth and heading. A typical display (Figure 1) from HYDROpro shows the use of a backdrop image of a harbour with two dredgers, two barges and a work boat being tracked. Figure 1: HYDROpro Navigation tracking 5 vessels on a dredging project The tracking PC can be located onshore or on vessel itself such as an oil rig. When passively tracking vessels a UHF radio link is typically used. Each remote vessel transmits its position in turn in their allocated time slot. This method is called Time Division Multiplexing. The message transmitted from the remote vessel must also have a header with its ID number so HYDROpro at the base can decode the data to a unique vessel. Trimble Navigation Limited 645 North Mary Avenue Post Office Box 3642 Sunnyvale, CA in North America outside North America Fax MAR Page 1

2 At the base each vessel tracked can have its true outline shape, name and colour defined. Each vessel can also have its own target point to aim for and details such as the bearing and distance to can be displayed in the Text windows on the PC. A user can define a real time report to be produced at any interval to include vessel name, time, date, speed, heading and associated data. This can be sent to an ASCII file and output to another computer if required. In more advanced applications it will be possible to transmit targets to specific remote vessels. In this case HYDROpro will send the message and confirm the message was received by the remote vessel. It will try communicating a number of times and if the communication fails (eg out of range) the operator is advised. In this mode the central HYDROpro system polls all the vessels for positions so a radio data link can be used without the need for time division multiplex and ID. In this mode each vessel will require HYDROpro Remote to be installed for display and helmsman control. This adds more functionality to the system if required such as when the vessels lays its anchor or dumps its load the helmsman can press a button and the position and status is transmitted to the central system for updating onscreen and reporting to file. Figure 2: HYDROpro Remote display on Tug 1 shows Rig and other Tugs and anchor lines. MAR Page 2

3 HYDROpro Remote In those cases where the vessels require visual guidance and remote updating HYDROpro Remote is recommended. It has been tailored for anchor handling tugs and dump barge positioning. The customization includes simplification and operator restrictions. Many of the features in HYDROpro Navigation are available such as background charts, multiple equipment interfaces, etc. Extra features include: Sending target points to remote vessels Guidance to the dump site or along the line between Barge winch and anchor target Remote Vessel tracking a continual update at the base HYDROpro system of anchor positions and status, or dump site coordinates, and all other vessels positions. Anchor / dump position reports (ASCII, printed) User Permissions: User permissions allow a supervisor to lock a field operator out of critical configuration dialogs. It also ensures that displays cannot be accidentally closed. User Permissions is ideal for anchor handling and dump barge systems where you want the operator to have restricted rights to the system. When the system is in operator mode it will automatically start up in Online status. Multiple display Frames let you set up a group of displays suitable for the Tug Helmsman and other personnel (eg. Second helmsman) Inexpensive software. HYDROpro Remote is available now. The master tug controller capability (ie. The central controlling HYDROpro system) will be added to the next release of HYDROpro Construction early 2001 so that anchor or dump coordinates can be issued from the barge / rig / shore office and the status and position of the anchors or dump can be tracked from the central master system. MAR Page 3

4 Customer Application 1 Tracking and Controlling Sand Dumping barges Singapore Hyundai who are a large marine construction company in Singapore have a contract to barge in sand and dump it accurately at reclamation sites around Singapore. Figure 3: Map of Singapore massive land reclamation projects are underway. A tracking system is utilized to track a number of barges and display the data for management reasons. The sand is sourced from outside Singapore waters and the maximum range is over 30kms from the tracking system in Singapore. The barges have DSM212L DGPS receiver onboard that use the Singapore beacon signals for DGPS corrections. The barges were interfaced to a TAIT T2000 MKII UHF datalink (Figure 4) operating in the UHF band. Only one frequency channel was allocated for this task as urgent mobilisation was required. Each barge transmits its position and status back to the HYDROpro system at Singapore and a screen display similar to that in Figure 1 is used. Data such as vessel name, time, date, map grid position, speed, heading is recorded to an ASCII file by HYDROpro. The system is being upgraded to allow the operator in Singapore to send dump positions to each barge and track their positions. This upgrade will involve placing HYDROpro Remote onto the barges so that the shore based operator of HYDROpro can type in coordinates for a dump site then transmit that to the barge HYDROpro Remote. The HYDROpro Remote graphically displays the new site and gives the helmsman guidance information to it. When the dump is occurring the helmsman presses a button which sends the actual dump position to the shore system for visual update and recording. MAR Page 4

5 Figure 4: TAIT T2000 MKII transceiver used with Time Division Multiplexed reporting and unique ID header message as an option. Equipment used The Singapore based central tracking system uses: 1 x HYDROpro Navigation software 1 x TAIT T2000 MKII transceiver with hi gain antenna Each dump barge uses: 1 xdsm212l GPS receiver 1 x TAIT T2000MKII transceiver with intelligent modem installed (TDMA, ID#) Upgrade will include HYDROpro Remote software on laptop PC on each barge MAR Page 5

6 Customer Application 2 Petrobas Brazil The client is placing a new oil pipeline on the seafloor between oil platforms and has 13 rock dumping vessels and tugs operating that drop rock over the top of the pipe to protect it. They track the position and heading of all the vessels from one of the oil platforms using HYDROpro so they can plan the most efficient use of the vessels. The client has Trimble 4700 GPS on the vessels connected to their own software systems for dynamic positioning control. In this case they did not require HYDROpro Remote on the vessels but they wanted to use Pacific Crest UHF radios to transmit positions of the vessels to the HYDROpro tracking PC on the platform. NMEA position and heading messages are output from the 4700 receivers at 1 Hz. This was filtered by the Trimble B1120 Packet Controller which adds a predefined identification string and transmits that data in its allocated time slot. The B1120 unique identification number is set by an internal switch and uses the NMEA UTC time as the basis to synchronise on. Figure 5 shows the B1120 which is inexpensive and simple to install. The central HYDROpro system receives the data from all vessels sequentially and displays all vessels with their own vessel shape, name, position, and heading. The features and advantages of this approach are: Simple radio system used - Only 1 radio frequency is used with a technique called Time Division Multiplexing There is no need for any computer on the vessels to format data Low cost and reliable tracking system using readily available radio link There is a text and graphical record of all the vessels at a given time Extendable to add additional data such as depth to the report messages and guidance on the rock barges via HYDROpro Remote software Figure 5: B1120 Packet Controller plugs directly into GPS and passes NMEA data plus its ID, in its allocated time slot, to the radio transmitter. MAR Page 6

7 Equipment used The central tracking system uses: 1 x HYDROpro Navigation software 1 x Pacific Crest RFM96W ( 1 x 4700 RTK base station transmitting CMR corrections Each dump barge uses: 1 x 4700 RTK receiving corrections with internal radio 1 x B1120 Packet Controller set with an ID# 1 x Pacific Crest RFM96W transceiver MAR Page 7

8 Customer Application 3 Precise Tracking of movement of drilling platforms Alaska For reasons of environmental monitoring and protection the client needs to track the precise position of drilling platforms located on sea ice islands. Real-time kinematic GPS is used so that movements of a few centimetres can be detected. The extremely cold conditions mean a minimum set of equipment is allowed on the drilling platforms and when the weather conditions deteriorate then all personnel are removed back to the mainland. The closest land suitable for an RTK base station is a small island shown in the diagram labelled Base Station& Tracking. At this point a 4700 base station, UHF radio transceiver and HYDROpro are housed. RTK corrections are transmitted to all mobile GPS from this station. Using Time Division Multiplexing in the radio transceivers the precise position and status from the drilling platforms are transmitted back using the same radio system and tracked on HYDROpro at the Base Station. If the Base Station has to be temporarily abandoned due to weather conditions the drilling platforms position can still be tracked at the Secondary Tracking station. The radio link used is a TAIT T2000 MKII which is available in a number of frequency bands and power settings. A special modem is added internally to ensure there is no collision of RTK correction data with the position reporting messages. Each mobile system is assigned a unique ID which is transmitted in the header to the position and status reports. Drilling Platforms Base Station & Tracking 15 kms Secondary Tracking Station Figure 6: The position of the drilling platforms on the ice were monitored continuously for movement. RTK corrections from the Base Station (1Hz) and position replies from the platforms were all possible on the one radio datalink. MAR Page 8

9 Equipment used The central tracking system uses: 1 x HYDROpro Navigation software 1 x 4700 RTK base station transmitting CMR corrections into TAIT radio (see next item) 1 x TAIT T2000MKII for extreme cold weather with double yagi antenna for transmitting CMR and receiving tracking messages Each remote site uses: 1 x 4700 RTK receiving corrections via TAIT radio (see next item) 1 x TAIT T2000MKII 25 watt transceiver with yagi antenna, and intelligent modem installed (TDMA, ID#). For receiving CMR and transmitting tracking messages MAR Page 9