User's Manual

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JMA-9172-SA Instruction Manual > 5.OPERATION OF TARGET TRACKING AND AIS > 5.1 PREPARATION
If the mode is ground stabilization, SOG/COG used for own ship's information in
target tracking. If the mode is sea stabilization, SPD (speed through the water) /
HDG (heading) used for own ship's information in target tracking.
AIS (Automatic Identification System) function
The AIS function shows the target’s information on the radar display, using other
ship's information sent out from the AIS unit.
5.1.1 Collision Avoidance
5.1.1.1 Problems of Collision Avoidance in Navigation
Marine collision avoidance is one of the problems that have been recognized from
of old. Now, it will be described briefly who the collision avoidance is positioned
among the navigational aid problems.
The navigation pattern of all mobile craft constitutes a system with some closed
loops regardless of the media through which the mobile craft travels, whether air,
water, the boundary between air and water, or space. This pattern consists of two
closed loops in principle, one of which is a collision with another mobile craft and
the other is a loop of finding a right and safe way to reach a predeterminate
destination. Fig. 5-1 shows the conceptual diagram of navigation pattern by MR.
E.W. Anderson. The closed loop of collision avoidance is shown on the left side
and the closed loop of finding a right course on the right side.
Fig 5-1: Navigation Pattern
Destination
Mancuver
Cource and
speed
Course
Ship traveling in controlled condition
Insrument or
judgement
Control
loop
Compass
and log
Caluculati
on
Fixing by radio wave ,
visual and celestial
observation
Judgement
Visual and radio
watch
Traffic rule
Cllision
avoidance loop
Vessel’s Spacing loop
Collision avoidance Decision of cource
Guide loop
Dead
reckoning