Documentation HG G-73650ZD | English, Revision 05 | Date: 09.03.2017 | www.goetting-agv.com
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Chapter 2: Basic Principles of Track Guidance
The transponder position in direction of travel is only output as the posi pulse when the cen-
ter of the transponder antenna is crossing the transponder. When there is no transponder
underneath the antenna, the antenna delivers no position.
There may be at most one
transponder underneath the antenna at any given time.
The parameters of the tran-
sponder antenna are set via a RS 232 interface which is described in the antenna manual.
Figure 4
Determination of antenna positions underneath the vehicle
The transponder antennas are 1.5 dimensional. That means that the relative transponder
position in direction to the long side of the antenna is measured. In direction of the short
antenna side only the crossing impulse (posi pulse) is available, which is generated when
the transponder passes the center of the antenna. The navigation controller associates a
certain task with each antenna number:
Antenna 1: Front (if needed)
Antenna 2: Vehicle center, rotated by 90
o
(if needed)
Antenna 3: Rear
The simplest form is a set-up with a single antenna.
2.3.2.1.1 Single Antenna Evaluation – Calculation of the Position with one Antenna
Figure 5
Single antenna: Placement
ATTENTION!
In order to be able to calculate a position it is normally necessary to detect more than one
transponder!
Vehicle X
Vehicle Y
Front
Antenna 1
Antenna 2
Antenna 3
Ant 3
Position X
Ant 3
Position Y
Ant 1
Position Y
Ant 1
Position X
Ant 2
Position X
Ant 2
Position Y
Vehicle X
Antenna 3
Vehicle Y
Front