Kongsberg MaritimeMDL's Fanbeam®4.2 system has many advantages. Our customers tell us that the Fanbeam®4.2 is straight-forward to set up, performs excellently during short range

Kongsberg Maritime

Fanbeam 4.2, Operations Manual

Measurement Devices Limited

Reference: Issue #1 Jan-2011

Version: 1

Supplier:

359132/A

Measurement Devices Limited Silverburn Crescent, Bridge of Don, Aberdeen AB23 8EW, Scotland, UK

UK: +44 1224 246700 USA: +1 281 646 0050 http://www.mdl.co.uk

Measurement Devices Limited

Fanbeam®4.2 Operators Manual

Issue #1 - Jan-2011 for

End Users / Installers / Engineers

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Measurement Devices Limited Fanbeam®4.2 Operators Manual

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Table of Contents 1 Fanbeam Operators Manual...................................................................................................... 4

1.1 Document Revision History............................................................................................................. 4

2 System Description ................................................................................................................... 5 2.1 Fanbeam® 4.2 Precision Positioning and Tracking System ............................................................ 5 2.2 System Schematic .......................................................................................................................... 6 2.3 Principal of Operation ..................................................................................................................... 7 2.4 Waste Information & Disposal......................................................................................................... 7

3 Operational Considerations...................................................................................................... 8 3.1 Typical Installation .......................................................................................................................... 8 3.2 Targets ........................................................................................................................................... 8

3.2.1 Target Types and Properties....................................................................................................................8 3.2.1.1 Reflective Tube Targets .................................................................................................................................................. 8 3.2.1.2 Prism Cluster Targets ..................................................................................................................................................... 9

3.2.2 Target Installation & Position ...................................................................................................................9

4 Control System – Human Machine Interface ......................................................................... 10 4.1 Operator Input............................................................................................................................... 10

5 Control Software – Single Target ........................................................................................... 11 5.1 Setup ............................................................................................................................................ 11

5.1.1 Fanbeam ................................................................................................................................................11 5.1.1.1 Fanbeam I/O................................................................................................................................................................. 11 5.1.1.2 Data Adjustments.......................................................................................................................................................... 12 5.1.1.3 Raw Data Logging ........................................................................................................................................................ 12 5.1.1.4 Target Speed Units ....................................................................................................................................................... 12

5.1.2 Gyro 12 5.1.2.1 Gyro I/O ........................................................................................................................................................................ 13 5.1.2.2 Gyro Options................................................................................................................................................................. 13

5.1.3 Data Output ............................................................................................................................................13 5.1.3.1 Enable Data Output....................................................................................................................................................... 13 5.1.3.2 Output Format............................................................................................................................................................... 14 5.1.3.3 Output I/O ..................................................................................................................................................................... 14 5.1.3.4 Data Adjustments.......................................................................................................................................................... 15 5.1.3.5 Output Test Mode ......................................................................................................................................................... 15

5.1.4 Alarms ....................................................................................................................................................15 5.1.4.1 Alarm Sound ................................................................................................................................................................. 15 5.1.4.2 Target Loss Sound........................................................................................................................................................ 16 5.1.4.3 Minimum Range Alarm.................................................................................................................................................. 16 5.1.4.4 Maximum Range Alarm................................................................................................................................................. 16 5.1.4.5 Bearing Alarms ............................................................................................................................................................. 16

5.1.5 Colours ...................................................................................................................................................17 5.1.5.1 Colour Schemes ........................................................................................................................................................... 17 5.1.5.2 Text Readouts............................................................................................................................................................... 17 5.1.5.3 Graphics Display........................................................................................................................................................... 17 5.1.5.4 Restore Default ............................................................................................................................................................. 17

5.1.6 Vessel Outline ........................................................................................................................................18

5.2 Graphic Options............................................................................................................................ 19 5.3 Readouts ...................................................................................................................................... 20 5.4 Target Filter and Display Tabs ...................................................................................................... 20

5.4.1 Filtering Parameters Tab........................................................................................................................21 5.4.1.1 Target Window Size...................................................................................................................................................... 21 5.4.1.2 Range Cut Offs ............................................................................................................................................................. 22 5.4.1.3 Target Quality Filters..................................................................................................................................................... 22 5.4.1.4 Options ......................................................................................................................................................................... 22

5.4.2 Auto-Level Filtering Tab .........................................................................................................................23 5.4.3 Position Prediction Display Tab .............................................................................................................24 5.4.4 Tracking Confidence/ Spurious Target Tab ...........................................................................................25

5.4.4.1 Tracking Confidence ..................................................................................................................................................... 25 5.4.4.2 Spurious Targets........................................................................................................................................................... 26

5.5 Status Bar..................................................................................................................................... 26 5.6 Track ............................................................................................................................................ 27

5.6.1 Target Acquisition ..................................................................................................................................27 5.6.2 Target Tracking ......................................................................................................................................29



5.6.2.1 Tilt................................................................................................................................................................................. 29 5.6.2.2 Tab ............................................................................................................................................................................... 30 5.6.2.3 Acquire ......................................................................................................................................................................... 30 5.6.2.4 Back.............................................................................................................................................................................. 30 5.6.2.5 Displays During Tracking .............................................................................................................................................. 30

5.7 Park .............................................................................................................................................. 30 5.8 Command..................................................................................................................................... 31

5.8.1 The Fanbeam® Settings ........................................................................................................................31 5.8.2 The Fanbeam® Controls........................................................................................................................32 5.8.3 The Filtering Parameters........................................................................................................................32

5.9 Exit ............................................................................................................................................... 33

6 Control Software - Multi-Target .............................................................................................. 33

1 Fanbeam Operators Manual

IT IS IMPORTANT THAT YOU READ THIS MANUAL CAREFULLY BEFORE USING THE SYSTEM. ©Copyright 2010 Measurement Devices Limited. Reproduction in whole or in part, including utilisation in machines capable of reproduction or retrieval, without the express written permission of MDL is prohibited. Reverse engineering is also prohibited. Software Version 2.00 and above. ©Copyright 1988 – 2010 Measurement Devices Limited. The programs that control this product are copyrighted and all rights are reserved. Reproduction, adaptation, or translation of those programs without prior written consent of Measurement Devices Limited is prohibited. The information in this manual is subject to change without notice. Some names referred to within this document are trademarks.

1.1 Document Revision History

Issue Date Initials Notes

1 Dec 2010 KSP



2 System Description

2.1 Fanbeam® 4.2 Precision Positioning and Tracking System

MDL's Fanbeam®4.2 is a laser radar system designed for repetitive, high accuracy positioning and tracking of marine vessels, and static and semi-static anchored structures. The system is primarily used to control or assist automatic docking of a vessel next to a platform, jetty or other vessel. Traditionally, three sensors are employed onboard a vessel involved in dynamic positioning operations. MDL's Fanbeam®4.2 compliments differential GPS (DGPS) and can assume a primary role when differential signals are lost or become ineffective. The system is also widely used to position seismic vessels gun array floats as the vessel surveys the latest oilfield prospects.

ADVANTAGES MDL's Fanbeam®4.2 system has many advantages. Our customers tell us that the Fanbeam®4.2 is straight-forward to set up, performs excellently during short range operations, high accuracy is achieved consistently, the system utilises intrinsically safe targets, requires very little maintenance and is low cost compared to other systems. This versatile laser system can be employed as a primary or backup system and is considered a valuable alternative or complementary system to DGPS and other navigational aids

• Performs Excellently During Short-range Operations

• Achieves High Accuracy's Consistently

• Utilises Inexpensive Intrinsically Safe Targets

• Rugged Design

• State-of-the-art Technology

• Long Product Life

• Meets Needs of a Diverse Range of Applications

• All Weather Operation

• Valuable Alternative or Complementary to DGPS

• Excellent Standalone or Backup System



2.2 System Schematic

DP Feed ��

Gyro Input ��

HMI Cable (PS/2)

Power Cable

Deck Cable

AC Mains from UPS

Data Cable (RSXXX)

VGA Cable

Vessel Forward



2.3 Principal of Operation

The Fanbeam is a laser based relative positioning system, which emits vertically divergent laser pulses to measure the distance to custom made reflective targets. The laser uses the time-of-flight principal to measure range whilst an optical angle encoder is used to measure the relative angle for each range. The laser is mounted on a horizontally rotating yoke, which also allows for vertical adjustments to cater for height differences between the target and the Fanbeam. The system is controlled by software running on an embedded PC control system that provides the operator interface. A data feed to a peripheral system (such as a DP) is provided from the control PC, which is usually on the bridge of the vessel.

2.4 Waste Information & Disposal

The crossed-out bin symbol, placed on the product, reminds you of the need to dispose of the product correctly at the end of its life. In this way you will assist in the recovery, recycling and reuse of many of the materials used in this product.

• Where possible recycle your packaging.

• With your help it is possible to reduce the amount of electrical and electronic waste ending up in landfill and to improve quality of life by preventing the release of potentially hazardous substances into the environment. This product may contain substances that can be hazardous to the environment if not disposed of properly.

• Electrical and electronic equipment should never be disposed of with general household waste but must be separately collected for their proper treatment and recovery.

• At the end of the life of your product the end-user may have an obligation to ensure that this Waste Electrical and Electronic Equipment (WEEE) is separately collected and to obtain and retain proof that it was handed to a waste management company who treated and disposed of it in an environmentally sound manner.



3 Operational Considerations

The system is relatively easy to setup and operate and is designed to minimise operator interaction as much as possible. There are, however some key points that all operators should consider when using the Fanbeam.

3.1 Typical Installation

The Fanbeam is most commonly located just above the aft wheelhouse on a mounting plate above the hard-rail. This usually affords the system a good line of sight to the aft, which is normally the “working end” of the vessel in most operational situations.

Other configurations are possible depending upon the kind of vessel and its expected operational needs. Many larger vessels now have multiple mounting locations (port/starboard) with cables run in. MDL can provide guidance and assistance with non-standard installations and cabling as required.

3.2 Targets

The reflective targets required to measure a range are of a custom design specifically optimised for use with the Fanbeam.

3.2.1 Target Types and Properties

There are two main target types available for the Fanbeam system. These have differing properties and should be selected according to the operational requirements.

3.2.1.1 Reflective Tube Targets

Reflective tube targets are the most commonly used target type. Generally selected due to their ease of installation and low cost, the tube target is a good general-purpose target for short-range operations. The tube target will provide a good reflection at ranges of up to 150m or further depending upon conditions. Tubes also have the advantage of a 360º angular coverage, meaning that target orientation is not a consideration.

NOTE: MDL do not recommend the usage of non-approved targets with the Fanbeam system.



3.2.1.2 Prism Cluster Targets

Various prismatic target configurations are available from MDL for use with the Fanbeam where long-range performance is desired. The reflective properties of the prisms are such that when two are stacked vertically, the maximum 2000m-range capability of the Fanbeam is made possible. Single prisms can be used and will provide ranges of up to 1000m in the correct conditions. A single prism is, however, limited in horizontal angular coverage to 60º. Therefore, a range of prism clusters is available that takes vertically stacked pairs of prisms (providing 2000m range) and allows them to be horizontally offset by 45º increments. This provides a long-range target with an angular coverage that is configured by the number of prism pairs you stack.

2 x Prism Pairs (4-way cluster) 105º (60º + 45º)

3 x Prism Pairs (6-way cluster) 150º






Six Way Prism Cluster – 150º

3.2.2 Target Installation & Position

The position of the target is worth giving consideration to as a poorly located target can lead to degraded positioning and/or loss of tracking.

Key considerations when positioning a target are:

• Target Height Ideally the target should be roughly the same height as the Fanbeam. This reduces the need for tilting and the chance of target loss due to pitch and roll when working very short range

• Target Mounting A robust mounting arrangement appropriate to the target type should be used – even when the targets are semi-permanent



• Target Orientation Both target types need to be mounted vertically to match with the vertical orientation of the laser fan. Mounting tube or cluster targets horizontally will significantly reduce the effectiveness of the target.

• Target Range If possible to mount a target where the range to the laser will be greater rather than very short can help to mitigate issues relating to target height.

• Target Visibility The laser requires a clear line of sight to the target for optimum performance. Always ensure that the target is positioned away from locations where moving infrastructure or personnel can block line of sight to the target.

• Personnel Awareness Personnel on the platform or rig should be aware of what the targets are and what they are used for.

4 Control System – Human Machine Interface

The control system for the Fanbeam includes a custom backlit keypad and mouse pointer device that is designed to optimise the operator’s interaction with the system. The software is designed to correlate with the human machine interface (HMI) so that the system is intuitive, quick and easy to operate.

• Function keys along top correlate with software

• Numeric keypad for value entry and target selection

• Cursor keys for navigating controls and manipulating values

• Dimmable LED backlight

• Glide-pad pointing device with no moving parts

• Left and right mouse buttons

• Tactile buttons with raised profiles for touch orientation

• Bracket or panel mount variants

• Integral buzzer for alarm function

4.1 Operator Input

The HMI makes two forms of input available to the user. These are the keyboard and the integrated pointing device (mouse). The keyboard has the following keys:

F1-F6 Used to quickly navigate options in the menu bar

Cursor UP Used to increase parameter values available in the software

Cursor DOWN Used to decrease parameter values available in the software

Cursor LEFT Used to move focus to next parameter available in the software

Cursor RIGHT Used to move focus to previous parameter available in the software

ENT Used to activate particular options in the software

0-9 Used to select target for tracking or enter numeric values in the setup

DEL Used to initiate target re-acquisition or delete values entered in the setup

DIM UP / DOWN Used to adjust the LED backlight level on the HMI



The pointing device is the equivalent of a two-button glide pad, similar to that found on many laptops. It allows the user to move a cursor around the screen and press software buttons by using the left mouse button. The right mouse button is only ever used to move the graphics display. For most purposes, the keyboard is the quickest way of interacting with the software and the shortcut keys should be learned to facilitate most effective use of the system. More information on the shortcut keys is available throughout the remainder of the operators manual.

5 Control Software – Single Target

The Fanbeam system is most commonly used in a single target-tracking mode of operation. This section relates to the operation of the control software associated with this mode.

5.1 Setup

The setup dialog contains various configuration options that can only be accessed when the system is offline (i.e. not tracking targets). Some of these options must be selected with care as they can impact on the operation of the system overall and it’s interaction with peripheral systems such as a dynamic positioning system.

5.1.1 Fanbeam

5.1.1.1 Fanbeam I/O

This dialog allows the operator to configure the I/O settings for the Fanbeam (or simulator). Typically this will be set to a serial port when working with hardware and a network socket when working with a simulator. Please refer to the common I/O dialog guide for more information on configuration. Also refer to the platform specific configuration for details of settings required for a specific hardware platform.



5.1.1.2 Data Adjustments

These parameters allow for data offsets to be made to the raw information being received by the software from the Fanbeam hardware. Generally these are left as zero as the information being provided is for relative movement detection only.

NOTE: These values are applied directly to raw data prior to any display in the software. If either value is non-zero, the data displayed will be modified rather than raw.

• Delta Height This parameter allows for a simple range reduction to be performed on the measured range, based on an assumed height difference between the target and the Fanbeam laser head.

• Bearing Correction This parameter allows for a simple angular offset to be applied to the measured bearing for all targets and position updates reported by the Fanbeam.

5.1.1.3 Raw Data Logging

New function. Not available until further testing has been carried out.

5.1.1.4 Target Speed Units

The software automatically calculates a target speed when tracking. Two speed units of measure are available for display purposes:

• Knots

• Meters per second

5.1.2 Gyro

An optional Gyro interface is available for the purposes of aiding the system re-locate a lost target and to optionally “north up” the display.



5.1.2.1 Gyro I/O

This dialog allows the operator to configure the I/O settings for the Gyro (or simulator). Typically this will be set to a serial port when working with hardware and a network socket when working with a simulator. Please refer to the common I/O dialog guide for more information on configuration. Also refer to the platform specific configuration for details of settings required for a specific hardware platform.

5.1.2.2 Gyro Options

• Gyro Enabled This option allows the user to toggle the Gyro interface on and off.

• C Minus O This parameter allows for a known offset to be entered in to be applied to raw gyro data.

• Rate This parameter tells the software how often to expect heading data and therefore how long to wait between telegrams before timing out and warning the operator.

• Standard Deviation This parameter allows for a known standard deviation to be input allowing the software to take account for this in statistical calculations

5.1.3 Data Output

Various data output telegrams are available for interfacing the system into dynamic positioning and survey solutions.

5.1.3.1 Enable Data Output

Allows for the data output to be toggled on and off. Some versions of the system may have this disabled (stand alone systems) at a licence level.



5.1.3.2 Output Format

This button brings up a dialog with detailed information regarding the various telegrams available in the software for interfacing to a peripheral system. Details of the various telegrams can be found in the Installation & Commissioning Guide.

• Ident

This value will generally be set to one, but can be changed to dictate the ID value in some of the telegrams.

• Type This drop down list allows for the selection of an output telegram. Details for the selected telegram are displayed at the bottom of the dialog. Please refer to the installation manual for details of the various telegrams available.

NOTE: Great care should be taken to ensure the correct telegram is used. Sending incorrectly formatted data to peripheral systems can result in un-predictable behaviour.

5.1.3.3 Output I/O

This dialog allows the operator to configure the I/O settings for the Data Output. Typically this will be set to a serial port or network socket depending upon the peripheral system. Please refer to the common I/O dialog guide for more information on configuration. Also refer to the platform specific configuration for details of settings required for a specific hardware platform.



5.1.3.4 Data Adjustments

These parameters can be applied to the data output prior to transmission. Typically they will be zero, but could be used to re-position the hardware on the vessel without the peripheral system being re-configured.

• X Offset

• Y Offset

NOTE: These parameters should only be used with great care. The displayed information on the software will not be effected by these parameters, only the output data.

5.1.3.5 Output Test Mode

This function allows for the testing of an interface to a peripheral system without actually tracking a target. Telegrams of the currently selected type are sent using the current I/O settings with test data values.

5.1.4 Alarms

5.1.4.1 Alarm Sound

The software has the ability to produce audio notifications when a tracked target meets the alarm criteria.

• Open This button leads to a file open dialog allowing the user to browse for and select a .WAV file to be played when the alarm criteria are met.

• Play This plays the currently selected alarm sound



5.1.4.2 Target Loss Sound

• Open This button leads to a file open dialog allowing the user to browse for and select a .WAV file to be played if the tracked target is lost.

• Play This plays the currently selected target loss sound

• Audio Alarm on Target Loss Some operators may wish to disable the audio notification for target loss. This allows this to be done.

• Sound Buzzer On Target Loss Some platforms may not have audio functionality. In these cases, the HMI can be configured to produce a beep in place of the audio notification. Selecting this option requires an HMI to be attached.

5.1.4.3 Minimum Range Alarm

This option can be used to create an alarm status when the tracked targets’ range falls below a specified value. When applied alone, the effect is to create a “range ring” around the Fanbeam.

5.1.4.4 Maximum Range Alarm

This option can be used to create an alarm status when the tracked targets’ range reaches a specified value or more. When applied alone, the effect is to create a “range ring” around the Fanbeam.

5.1.4.5 Bearing Alarms

These options can be used to create an alarm status when the tracked targets’ bearing falls out with the specified angular sector. When applied alone, the effect is to create a “safe sector” relative to the Fanbeam. When all three of the above alarm parameters are enabled, they combine to create a “safe segment” area inside which the target must be positioned. If the target moves out with the segment, an alarm condition will be triggered.



5.1.5 Colours

5.1.5.1 Colour Schemes

The software display caters for two user configurable colour schemes. These are intended to allow for quick switching between daylight colours and night-time (dimmed) colours. Each main graphical component can be individually configured. Clicking on components button allows the user to select a colour from a dialog.

5.1.5.2 Text Readouts

The text readouts (Range, Bearing, Level, Accuracy & Gyro), each have two colours (test and background) with three possible states (Tracking, Lost and Alarm).

5.1.5.3 Graphics Display

The graphics display components are as follows:

• Background – the background colour of the graphic display

• Polar Grid – the range rings and angular projections on the graphic display

• Annotations – used for text and vessel outline on the graphic display

• Targets – there are three colours assigned to discriminate between the tracked one, a lost one and any spurious targets

• Alarm Sector – colour used for hatched alarm regions on the graphic display

• Alarm – colour used for tracked target that is out with alarm parameters

5.1.5.4 Restore Default

There are many possible colour scheme configurations possible. This option allows for default ones to be quickly selected.



5.1.6 Vessel Outline

The graphic display includes the facility to add a vessel outline as a visual guide to help identify targets relative to the vessel rather than the Fanbeam itself. This feature is intended as a visual aid only, and as such these parameters need only be approximate. The date output or displayed values are not affected by these parameters.

• Display Vessel Outline This allows the user to toggle the vessel outline on and off

• Show Sweep Angle This option allows for the graphical laser sweep line to be disabled

• Length Approximate length of the vessel in meters

• Width Approximate width of the vessel in meters

• Fanbeam X Port – Starboard offset in meters of Fanbeam from the vessel centre. Positive X is starboard of centre line and negative X is port.

• Fanbeam Y Forward – Aft offset in meters of Fanbeam from the vessel centre. Positive Y is forward and negative Y is aft.

• Angular Offset This allows for a known angular offset between the Fanbeam and the vessel centre line to be input.

• Orientation Limited to 30-degree increments, this value rotates the entire graphic display to correlate with the locus of the monitor relative to the vessel.



5.2 Graphic Options

Above the main graphic display is a row of iconised buttons. These relate to the graphic display and allow various functions and options to be accessed at any time by the operator.

• Zoom In Increases the graphic display zoom factor. This option is disabled if Auto-Display Scale is active.

NOTE: If the zoom factor is too high then tracked and/or spurious targets my not be visible on the graphic display.

• Zoom Out Increases the graphic display zoom factor. This option is disabled if Auto-Display Scale is active

• Auto-Display Scale This option is designed to remove the need to use the zoom functions. When enabled, the display will automatically scale to show the tracked target (when tracking) or all selectable targets (when acquiring).

NOTE: If the graphic display has been moved off centre (by right clicking and dragging), then this does not guarantee that the tracked target will be visible.

• Centre Graphics Display The graphic display can be moved around using the mouse pointer (right click and drag). This button can be used to easily centre the display again.

• Display Snail Trail This option toggles on and off the display of the tracked targets’ positional history.

• Display Target Dynamics This option toggles on and off the display of the tracked targets’ dynamic properties (speed & direction) as well as the direction arrow.

• Display North Up This option allows for a gyro heading value (when interfaced) to be used to orient the whole graphic display to North up.

• Daylight Colour Scheme Selects the daylight colour scheme (applies to whole user interface).

• Night Colour Scheme Selects the daylight colour scheme (applies to whole user interface).



5.3 Readouts

Each readout is used to display numeric data to the operator in such a way that is easy to understand and read even from a distance. Sometimes these readouts are also used to display the status of the system.

• Range The distance in meters to the currently tracked target.

• Bearing The angle in degrees (relative to the Fanbeam) of the currently tracked target.

• Level The signal strength of the current target

• Accuracy Quality indicator for the current target

• Gyro Heading data from the gyro (when interfaced)

5.4 Target Filter and Display Tabs

There are a range of additional controls and displays that can be accessed by way of the tabbed control at the bottom right of the operator display. The function and purpose of each is described below:



5.4.1 Filtering Parameters Tab

The software performs a variety of target data filtering functions that can be configured by the operator, or, in some cases, made automatic. The target filtering parameters are described below:

5.4.1.1 Target Window Size

A target “window” is the primary method used to identify the tracked target This window is position based and follows the tracked target as it moves around relative to the Fanbeam. The window is defined in terms of the targets last observed range and bearing with an error margin defined by the operator.

The two parameters define the overall size of the window in the range and bearing domains (polar coordinates).

• Meters The overall size of the window in the range domain

• Degrees The overall size of the window in the bearing domain

NOTE: As the window is defined in polar coordinates, it is easier to relate it to target data. However, operators should be aware that the Cartesian dimensions of the window would increase with range.

NOTE: These parameters only have meaning once the system is tracking a target.



5.4.1.2 Range Cut Offs

A simple way of filtering out unwanted targets is to set a minimum, maximum or both range cut-offs. This has the effect of having the software reject target data that does not satisfy either or both of these parameters.

• Minimum The software will reject all targets observed with a range of less than the minimum range cut-off.

• Maximum The software will reject all targets observed with a range of more than the maximum range cut-off.

When one or more of these parameters is “infringed” (i.e. a target is rejected because of the parameter), the target will be displayed graphically as a “spurious” target and the infringed parameter will flash red.

NOTE: Operators should take care not to reject the valid target using these parameters.

5.4.1.3 Target Quality Filters

A common way of filtering out unwanted targets is to set a minimum level to a value just below the level of the tracked target. This has the effect of having the software reject target data that does not satisfy this parameter.

• Minimum Level The software will reject all targets observed with a level of less than the minimum level.

• Minimum Accuracy The software will reject all targets observed with an accuracy of less than the minimum accuracy.

When one or more of these parameters is “infringed” (i.e. a target is rejected because of the parameter), the target will be displayed graphically as a “spurious” target and the infringed parameter will flash red.

NOTE: Operators should take care not to reject the valid target using these parameters.

NOTE: Accuracy values are only in the range of 1 to 9. The real meaning of the value is the number of reflections received from a given target. Values 1 to 8 mean 1 to 8, but 9 means 9 or more. As such, it is recommended that targets be only used where they exhibit an accuracy of 9 consistently. A target with an accuracy of 8 is only 8 reflections away from not having been observed at all.

5.4.1.4 Options

There are two option toggle buttons relating to target filtering:

• Auto-Level Filtering This option toggles on and off the use of a software function that allows the minimum level parameter to be automatically calculated. See more about this function in the section on Auto-Level Filtering Tab.

NOTE: When this option is enabled, the Minimum Level control is greyed out and becomes a display for the calculated minimum level.



• Apply Filtering Parameters This option allows the operator to completely disable the filtering parameters (software does not reject any target). This can be useful to aid target identification in a cluttered environment.

5.4.2 Auto-Level Filtering Tab

The software has a built in function for autonomously controlling the commonly used level (signal strength) filtering parameters. By building up a history of the tracked targets’ level, the software is able to proactively set appropriate filtering values. The display on this tab allows the operator to see this happening in real time.

• Auto-Level Filtering This option allows the auto-level filtering function to be enabled or disabled.

• Clear The histogram will fill up with the last five minutes of level data for the tracked target. This button allows the operator to delete the oldest minute of data from the histogram. This can be used to remove outlier data from the function.

• Histogram The histogram itself is displayed purely for information purposes. It provides a very useful reference for optimising tracking performance using the Tilt function.

NOTE: The histogram always gathers data from the tracked target, even when the function is disabled. This means that the data can be applied instantly when the function is enabled.



5.4.3 Position Prediction Display Tab

The software includes a function for applying statistical methods to create a position prediction. This is then used to aid with spurious target rejection in situations where targets are very close together.

• Target Dynamic Properties The dynamic properties are identical to those shown on the graphics display. They provide readouts of relative target speed, direction and degrees of freedom.

• Position Prediction Display This graphical display gives a much closer view of the tracked target along with the predicted position and associated ellipse (centred about the predicted position) describing the error budget for that observation. The display scale will automatically change to accommodate the ellipse on the display area. The actual target observation is displayed as a cross with historic observations displayed as diamonds.

• Prediction Ellipse Parameters The measurements of the calculated Prediction Ellipse are displayed as readouts for the benefit of the operator. These include semi-major, semi-minor and bearing.

The software uses this function in situations where the traditional target discrimination is not enough. If a spurious target is present in close proximity to the tracked target (i.e. inside the target window), then the predicted position is compared with the targets seen by the system to determine which is the real one, and what to reject. This function is completely automatic and the tab is for information purposes only.



5.4.4 Tracking Confidence/ Spurious Target Tab

This tab provides the operator with displays relating to tracking confidence and spurious targets.

5.4.4.1 Tracking Confidence

The various calculated values available elsewhere in the software allows for a measure of tracking confidence to be garnered. An overall value (0-9) is generated by combining the following values together:

• Semi Major The larger dimension of the prediction ellipse gives a good measure of target predictability. Larger inputs lead to lower outputs into the combined confidence value.

• Target Speed

The target speed gives a fair measure of target predictability. Larger inputs lead to lower outputs into the combined confidence value.

• Level Spread

The spread of levels is defined simply as the difference between the highest and lowest values in the histogram. If there is a large differential, then the target is changing in characteristic over a short time frame, and there is more chance of spurious targets not being rejected by auto-level filtering.

• Successive Observations

Target tracking should be highly repetitive under normal conditions. If for some reason, the target is being occasionally lost, this will reduce the successive observations count leading to a reduced combined confidence value.

• Target Accuracy

The tracked target should normally have an accuracy of 9. If this value drops below 9 it will negatively influence the combined confidence value.



5.4.4.2 Spurious Targets

A secondary display is positioned at the bottom of this tab. This display relates to the detection and status of spurious targets by the system.

• Spurious Indicates if a spurious target (any target other than the tracked one) is visible to the Fanbeam.

• Filtered If there are spurious targets visible, this indicates if any of them are un-filtered (red).

• Inside Window If there are spurious targets visible, this indicates if any of them are positioned inside the target window (red).

• Result An overall spurious target status is derived from the combination of the previous three flags. Five possible states exist (0 = no spurious targets through 4 = unfiltered target inside target window).

5.5 Status Bar

The software has a status bar along the bottom of the display that is segmented into sections. Each one displays information about the software.

• Software Status This indicator provides information about software status at any given time. Examples of status include tracking target, target lost, tilting etc.

• Data Output The data output feed to the DP is a critical part of the whole system. This indicator allows operators to see the data telegram being sent in real time.

• Licence The software is protected by a hardware licence, which is detected at start-up and regularly thereafter. Some licences can be time limited, and in these situations a time remaining will be displayed here.

• Software Revision The version and release date of the software in use is displayed here so that operators can quickly determine what revision is in use.



5.6 Track

In order to track a target, the software must go through a target acquisition procedure where the operator is provided with options regarding what target to select. Once this is done, the system is almost completely autonomous, but there are still options available to the operator that can optimise the target tracking

5.6.1 Target Acquisition

Target acquisition is achieved by the hardware repeatedly performing 360º rotations whist the software lists all un-filtered targets with a unique ID. The operator can then select the desired target for tracking by selecting the appropriate ID. Various other options are available to the operator during target acquisition that are designed to aid the observation of the valid target and the rejection of any spurious ones.



• Tilt

It may be necessary to tilt the laser up or down in order to see the desired target in the first place. It is most common to have to tilt the laser up to cater for a high target on a tall platform relative to a low Fanbeam on a small vessel. In between each acquisition rotation, the operator can tilt the laser up or down to one of seven pre-defined tilt positions. The control allows the tilt to be changed up or down at 5º intervals.

• Speed

It may be necessary to reduce the rotational speed of the Fanbeam in order to see more distant targets. The control allows for speed to changed up or down in 5º/s increments.

• Target Readout A list view of the un-filtered targets for each rotation is displayed in place of the readouts during acquisition. The list gives ID, range, bearing, level and accuracy for each target. Filtered targets will be displayed graphically (depending upon zoom factor) and the infringed filtering parameters will flash red.

• Target Filtering

If there are many spurious targets visible to the system. It may be necessary to filter these out using the filtering parameters. Usually this is a simple matter of looking at the target levels and setting a minimum level to reject the weaker targets.



5.6.2 Target Tracking

Once a target is selected in the acquisition phase, the software will begin to auto-track the selected target. Various options are available to the operator at this point as follows:

5.6.2.1 Tilt

Whilst the bulk of DP operations are focussed on holding the vessel in station, many are also concerned with moving a vessel around in a highly controlled way.

Therefore, the need may arise for the system to track a target over a range of distances. As the vessel comes closer to the structure, the height difference becomes more significant and the need to change the laser tilt angle may arise. The tilt control allows the operator to move the laser up or down by 5º without the need to re-acquire the target. This also allows for “fine-tuning” to be done by optimising the tracked signal strength (level) with different tilt angles.



5.6.2.2 Tab

This option allows the operator to quickly toggle between the various tab views available on the bottom right of the display without having to use the pointing device.

5.6.2.3 Acquire

This option takes the operator back to the target acquisition mode, stopping target tracking and any data feed to a peripheral system.

5.6.2.4 Back

This option stops target tracking and returns the operator to the initial start-up menu.

5.6.2.5 Displays During Tracking

Much of the user interface is designed to make the system as easy to monitor and interact with during target tracking as possible. The target readouts are large to ease reading from a distance and the controls are of a size that they can be manipulated quickly by mouse control and even faster by “hot-keys” on the keypad. If for any reason, the tracked target is lost, the system will provide an instant visual indication of this and optional audio notification. In many situations, the operator will not need to interact, as the system will always try to autonomously re-acquire the tracked target. The tracking confidence indicator also provides a quick way for the operator to quickly assess how the system is performing. A degradation in tracking confidence does not always mean there is a problem, but provides a means to quickly assess how much attention the system may require.

5.7 Park

When the Fanbeam® head is positioned at 180º, we call this the “Park” position. The Fanbeam® can be left in this position when not in use or switched off and can be useful for lens cleaning. Most importantly, however, is the fact that the Fanbeam® must be put into the park position before being removed and put in its transit case for shipping. Users must take care to remember that the Fanbeam® will not fit in its transit case otherwise and cannot be rotated manually.



5.8 Command

The Fanbeam® settings must be configured once the system is installed to tell the software how the hardware is interconnected. Clicking on the Command button on the MENU BUTTON BAR or pressing 4 displays the following dialog:

5.8.1 The Fanbeam® Settings

• Fanbeam® Port RS232 port to be used for communication with the Fanbeam® must be different to the data output port

• Tilt If an AUTOTILT Fanbeam® is used, the user can tilt the head of the laser up or down in 5º increments between +15º and –15º.

• Park Angle This option allows the user to specify the “Park” angle. Users should note, however, that for shipping purposes, the 180º option must be used.

• Speed Sets the rotational speed of the Fanbeam® in degrees per second.

Once happy with the FANBEAM® SETTINGS the user should be able to use the FANBEAM® CONTROLS to manipulate the instrument.



5.8.2 The Fanbeam® Controls

• The plan view circle depicts a plan view of the Fanbeam® in a white circle. The mouse can be moved over this circle to select a bearing to move the Fanbeam® to or scan between. Once the desired bearing is shown on the display below the circle, left click to move the Fanbeam® to that bearing, or right click to start scanning between the chosen bearing and the current bearing.

• The run buttons allow the user to set the Fanbeam® running continuously in a clockwise or counter-clockwise direction.

• The stop button cancels any of the above commands.

• The park button moves the Fanbeam® to the 180º position that is used for shipping the instrument.

Once the Fanbeam® is moving, any information for targets that is observed will appear in the OBSERVED TARGETS area and the DATA DISPLAY. Some targets may be ignored if they infringe the Filtering PARAMETERS.

5.8.3 The Filtering Parameters

These parameters are replicated on the main display and can be modified at any time.

• Minimum Range Any targets with a range lower than this value are ignored by the software.

• Maximum Range Any targets with a range higher than this value are ignored by the software.

• Minimum Level Any targets with a level lower than this value are ignored by the software.

• Minimum Accuracy Any targets with an accuracy lower than this value are ignored by the software.

• Auto Level Tracking A target’s level is dependant on many outside factors such as weather conditions and visibility. If this option is checked the level gate will remain lower than any observed target level.

• Apply Filtering Parameters This control allows the user to toggle on and off all of the filtering parameters. When this option is unchecked, all observations will be considered as real targets. With this option checked, any observations that fall out-with the gating parameters will cause an “infringement”. The coloured status indicators next to each gating parameter show gating infringements. The values shown are counts of each infringement since the scan began. These indicators will let the user know if the filtering parameters are set too high.

Valid Ranges Invalid Ranges

Fanbeam



5.9 Exit

The software can only be exited from the main menu when not tracking. A variety of options are made available on exiting the software as follows:

• Shutdown This option fully shuts down the embedded PC when selected. Power up can then only be achieved by means of the power switch on the Embedded PC.

• Restart This option performs a “warm” reboot of the embedded PC

• Exit This option can be used to exit from the control software back to the Windows operating system where alternate control software (such as multi-target) can be selected, or other configuration tasks may be performed.

• Cancel This option aborts the exit taking the operator back to the main menu.

6 Control Software - Multi-Target

Currently the Multi-Target control is available via a separate software programme, which is installed as default on all control systems. Accessing this can be done by following the Exit procedure defined in section 5.9. Operation of this software is described in a separate document included herein.

Documents

Kongsberg MaritimeMDL's Fanbeam®4.2 system has many advantages. Our customers tell us that the Fanbeam®4.2 is straight-forward to set up, performs excellently during short range