Helmsman’s Display Collision Detection
NaviPac-NT
NP3.4D-P12 / NP3.5
A14. Collision Detection
Optional real-time feature in Helmsman’s Display version 3.4.68
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Helmsman’s Display Collision Detection
Table of contents
Table of contents ________________________________________________________ 2
Revisions ______________________________________________________________ 2
Introduction____________________________________________________________ 3
Collision Detection ______________________________________________________ 3
Shapes/outlines (dynamic polygons) ____________________________________________ 3
Displaylines (static polygons) __________________________________________________ 3
Waypoints (circumferences)___________________________________________________ 4
Control________________________________________________________________ 4
Display________________________________________________________________ 6
Appendix A ____________________________________________________________ 8
Revisions
Revision
1.0
Who
JUS
Date
2005-09-12
Additions
Created
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Helmsman’s Display Collision Detection
Introduction
This document describes how to enable the Collision Detection feature in Helmsman’s Display
(HD) version 3.4.68 as part of NP3.4D-P12 (NP3.5).
The purpose of collision detection is to enable real-time tracking of dynamic objects
entering/intersecting safety zones (and other dynamic objects). Only autonomous dynamic objects,
i.e. object id interval [0;800[, are tested against other dynamic objects or safety zones.
Safety/alarm zones can be defined either as displaylines or waypoints:
•
Waypoints with applied circles/circumferences and/or applied outlines*. File format: .wp2
•
Displaylines/boundary-lines defining a closed area (polygon). File format: .dis/.shp
*applying an outline to a waypoint can only be done through the use of a jobfile.
Collision Detection
When this feature is enabled HD is each cycle monitoring all participating objects testing dynamic
objects against:
•
other Dynamic objects, with or without applied shapes/outlines
•
Waypoints (not RigMove anchors or proposed positions), with or without applied
circumferences and/or shapes/outlines
•
Displaylines, as closed polygons or not (the latter being auto-closed by HD giving
unpredicted results)
Shapes/outlines (dynamic polygons)
The operator must consider the design of each shape definition carefully. It’s virtually impossible to
handle any outcome of shape definition whether it’s defined as closed polylines/polygons (good) or
single line segments (bad), clockwise or counter-clockwise definitions (doesn’t matter), overlapping
or adjacent polygons (the former not handled), convex or concave polygons (both handled). In
other words outline definitions which are visually apparent to the human eye but not for the
computer.
Shapes/outlines are defined as relative coordinates around (0, 0), whether it’s the centre of gravity,
midpoint or some important reference point. See Appendix A.
Shapes/outlines can be applied to dynamic objects but only through the use of a jobfile where the
cross referencing will be stored.
Full dynamic polygon against polygon test is implemented, e.g. dynamic against dynamic and
dynamic against static.
Displaylines (static polygons)
Displaylines are similarly defined as shapes/outlines except for the use of absolute world grid
coordinates instead of relative coordinates.
Full static polygon against dynamic polygon test is implemented as well as static polygon against
static polygon, but as no displaylines are alive, the latter mentioned test is not in use.
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Helmsman’s Display Collision Detection
Also see Appendix A.
Waypoints (circumferences)
Safety/alarm zones may be defined as circumferences around the positions of the waypoints.
Shapes/outlines can be applied as well but only through the use of a jobfile where the cross
referencing will be stored.
If applied safety zone a circumference test against the safety zone will be conducted first.
Almost all types of circumference tests are implemented, e.g. circumference against circumference
test and circumference point inclusion test. However, circumference against polygon test is
presently not implemented. In this case the circumference against circumference test will
supersede.
Control
The Collision Detection is enabled in menu Options; Global Settings; Enable Collision Detection:
This option may also be used for resetting the Collision Detection, e.g. any occurring but ignored
Collisions will be re-listed/re-considered when disabling/enabling the option.
It is not possible to control which objects are participating in the collision detection. It is either all or
none.
When HD detects a collision the operator is alerted with a modeless pop up dialog:
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Helmsman’s Display Collision Detection
In this case the vessel (object 0) as well as the diver (object 7) has collided with the same waypoint
as seen graphically below.
In the Collisions dialog either press Ignore All or select a single collision and then press Ignore will
leave the collision detection(s) ignored, but still alive as long as the collision takes place. When a
collision has been avoided the internal union between the 2 objects involved is deleted. Then if a
collision between the 2 objects re-occurs the collision will be re-displayed whether the collision has
been previously ignored or not.
An option Sound alarm is added for audio alerts.
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Helmsman’s Display Collision Detection
Display
When collision(s) have been detected the collision(s) dialog pops up and the implicated objects will
be hatched accordingly to their present shapes/outlines/circumferences.
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Helmsman’s Display Collision Detection
In this case a dynamic polygon to static concave polygon collision has been detected.
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Helmsman’s Display Collision Detection
Appendix A
Displayline and shape/outline file format: HP plot (*.dis;*.shp). This section is equal to Table A1
found in ..\NaviPac\Displaylines\HD_Displayline.txt.
The HP plot format not to be mistaken with the HPGL file format which is a completely different file
format! Secondary HP plot type (.shp) is used for defining outlines/shapes of dynamic objects
(relative coordinates with gravity/centre in (0, 0)).
HP plot format general (3 (or 1) column(s)):
[<"name">], e.g.:"The coastlines of xxx" (only valid as the first line of the file)
or
<1.no><separator><2.no><separator><operation>[<comment>], e.g.:500000.00, 6000000.00, -2
or
[<# comment>] e.g.:# define area xxx
Supported separators: space/comma/tab/semicolon (and other non-number signs)
Supported operations:
X.xx,
Y.yy,
-2
# Pen up before moving to position [m]
X.xx,
Y.yy,
-1
# Pen down before moving to position [m]
X.xx,
Y.yy,
0
# Pen up after moving to position (same as +2) [m]
X.xx,
Y.yy,
1
# Pen down after moving to position [m]
X.xx,
Y.yy,
2
# Pen up after moving to position (same as 0) [m]
1a)Pen number, 1b)Palette,
3
# Select pen number (color) and palette
2)Line type,
4)Line width,
4
# Select line type and line width [m]
Ignored,
Ignored, 5
# Ignored
Ignored,
Ignored, 6
# Start polygon mode with FILL
Ignored,
Ignored, 7
# End polygon mode
Ignored,
Ignored, 8
# Ignored
Ignored,
Ignored, 9
# Ignored
Ignored,
Ignored, 10
# Start polygon mode with EDGE
Ignored,
Ignored, 11
# Start polygon mode with FILL and EDGE
Ignored,
Ignored, 12
# Ignored
1a)Pen number, 1b)Palette,
13
3)Line width,
# Select line width [m]
Ignored, 14
# Select pen number (color) for polygon filling
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Helmsman’s Display Collision Detection
1)Depth,
Ignored, 15
# Depth
Ignored,
Ignored, >15
# Ignored
4) Only valid with Line type 1 (solid)
3) Obsolete, use operation 4 instead
2) Supported windows line types:
0
Ignored
1
Solid
2
Ignored
3
Ignored
4
Dot
#____________
5
Dash
# ___ ___ ___ ___ ___ ___
6
Dash Dot
# ___ _ ___ _ ___ _ ___ _
7
Ignored
8
Dash Dot Dot
>8
Ignored
# _______________________
# ___ _ _ ___ _ _ ___ _ _
1) a)Supported colors, b)0=system palette (1.col.),1=alternative (ECDIS) palette (2.col.):
0
Black
Black
1
White
White
2
Red
Red
3
Yellow
Light Red
4
Green
Green
5
Cyan
Light Green
6
Blue
Blue
7
Magenta
8
Black
Cyan
9
Light Green
Light Cyan
10
Light Cyan
Dark Yellow
11
Light Blue
Yellow
12
Light Magenta
Buff
Light Blue
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Helmsman’s Display Collision Detection
13
Light Red
Brown
14
Orange
Magenta
15
Brown
Light Magenta
16
Beige
Beige
17
Buff
Ignored
18
Dark Yellow
Ignored
19
Dark Grey
Ignored
20
Grey
Ignored
21
Light Grey
Ignored
>21
Ignored
Ignored
See .dis file examples in directory $EIVAHOME\Displaylines\*.dis
See .shp file examples in directory $EIVAHOME\Setup\*.shp
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