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Guidance Control in Detail
English, Revision 07, Date: 07.03.2018
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The first column displays the serial numbers of the transponder tags. The second col-
umn includes the transponder or Sky-Trax codes. The following two columns stand for
the position in X or Y direction. In the fifth column the heading of the start transponder
is recorded in 1/100
o
. For Sky-Trax tags attribute 1 and 2 display the tag size in mm.
Due to size difference of the tags as well as differences in the height of the mounting
points deviations may occur. The correct value is derived from commissioning (see
chapter 4 on page 28).
2.3.2
Sky-Trax
This system is based on an image processing technology, usually using an upward di-
rected camera. The camera on the vehicle is positioned in such a way that it is able to
read the two-dimensional tags under the ceiling. Theses readings are transmitted
back and the relative position and rotational orientation will be supplied. Additionally
the tag code will be transmitted. If there is no tag in the camera's coverage area no
position will be transmitted. There may be several tags in the camera's detection
range.
As the Sky-Trax camera has only one ethernet-interface, its output must be converted
by the WLAN radio modem G 76431 via RS 232 (ethernet interface of the HG 61430 is
not yet available). The WLAN radio modem offers the additional advantage that the im-
ages captured by the camera can also be displayed on a stationary controller. This
facilitates an easy parameterization of the camera.
One disadvantage of the Sky-Trax System is the great distance between the tag and
the camera. The further away the tag is from the camera, the greater is the detection
range and area coverage of the camera. However uneven surfaces or a fully suspend-
ed vehicle have a negative effect. A position error caused by vehicle inclination de-
pends on the degree of tilt and the distance to the tag.
2.4
Vehicle Control Unit
The track guidance controller communicates with the vehicle control unit via CAN Bus,
Profibus or Ethernet. The vehicle control unit adapts the steering controller to the ve-
hicle. This offers the advantage of a standard interface. The customer can directly af-
fect the adaptation and is therefore able to make the necessary adjustments. Vehicle
control unit and steering controller may mutually monitor their communication. This
guarantees a higher level of security. The vehicle control unit is responsible for control-
Number
Code
X Pos.
Y Pos.
Attribute 1
Attribute 2
Attribute 3
Attribute 4
1
1
-2480
-4555
9000
0
0
1
2
2
-2462
-3171
0
0
0
0
3
46
6000
0
0
0
0
0
4
4336
9500
0
0
0
0
0
5
8012
3031
6891
9000
127
127
1
Table 5
Explanation transponder list