15. User Chart Control; Introduction; Objects Of User Charts - Furuno FEA-2107 Operator's Manual

15. User Chart Control

15.1

Introduction

User charts are simple overlay charts which the user makes for his own purposes. They can be displayed on both the
radar display and the electronic chart. These charts are intended for highlighting safety-related items like position of
important navigation marks, safe area for the ship, etc. User charts areas can be used to activate alarms and
indications based on user-defined danger symbols, lines and areas. When route or own ship estimated position is
going to cross a user chart symbol, line or area which is defined as a dangerous one, an alarm or indication is
generated by the system. For further details about chart alarms, see Chapter 11.
A user chart consists of points, lines and letter/number, symbols, etc. Size of user chart is limited to have the max.
number of items below:
•
200 Points
•
2000 Lines
•
1000 Symbols (alphanumerics)
•
50 Areas; an area can have 20 corner points.
The user chart is displayed on the radar display and its position and shape is based on the ship's actual position.
When own ship is moving in the area covered by the user chart, the elements of the user chart are superimposed on
the radar overlay, with max. 80 nearest elements displayed. The user charts can also be shown on the ECDIS
display. In this way the radar display can be kept as "clean" as possible for radar target detection.
15.1.1

Objects of user charts

Below is a description of the objects used in a user chart.
•
Line: You can define four different types of lines. Lines can be used in chart alarm calculation and/or display
on the radar:
•
Navigation lines: Displayed on both displays (radar overlay + ECDIS). Navigation lines are reference
lines for coast line.
•
Coast line: Displayed on the ECDIS display only. Coastal line is usually a well-defined (by chart
digitizer) multi-segment line showing the coastline. The user is able to create this type of line in case there
is no suitable chart available over desired area in ARCS or S57 format.
•
Depth contour: Displayed on the ECDIS display only. Depth line shows the chosen depth levels. The user
is able to create this type of line in case there is no suitable chart available over desired area in ARCS or
S57 format.
•
Route line: Displayed on both radar overlay and ECDIS. Route lines are zones for anchoring, traffic
separation lines, etc.
•
Area: User can define closed areas, which the system can use to detect safe water areas. If route or estimated
ship position is going to cross the area, the system generates a warning to the user. These areas can be used to
specify safe areas as defined by the master or by the policy of the ship's owner. They are always available
regardless of the type of chart material used.
•
Symbols: User chooseable symbols can be displayed on both displays or on the ECDIS display only. Symbols
are used to indicate buoys, light houses, fixed targets, wrecks, etc. Symbols can be used in chart alarm
calculation.
•
Tidals: Displayed on the ECDIS display only. Tidals can be used to make own notes about tides at user-defined
points.
•
Points: It doesn't itself have any symbol on the radar screen, but it is a very important element of a user chart
For further details, see paragraph 15.2 "What is a User Chart Point and How is it Used?".
15-1