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Guidance Control in Detail
English, Revision 07, Date: 07.03.2018
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It is the task of these tolerance definitions to protect a sufficient accuracy of the posi-
tion against incorrect measurements. Thus over short distances only a measurement
of high quality will be accepted. This prevents a positioning quality degradation
caused by incorrect readings.
The limits defining a position as too inaccurate can partly be adjusted or are defined
according to the tables in the reference manual. Those tables show that after 9 meters
any measurement will be accepted. This ensures the continuation of the operation af-
ter a long distance drive without transponders and avoids a system shut down. The
table shows practical, experience-based values.
2.3.1.2
Initialization of the Transponder Sensor Fusion
There are two options for the initialization of the transponder sensor fusion.
1.
The vehicle reads the start transponder. The start transponder is a normal tran-
sponder which only has one possible direction to be crossed. This may be the
case e.g. at a transfer station. The start transponder is marked accordingly and
the start heading is recorded in 1/100
o
. A start transponder is only evaluated
directly after the system has been switched on.
2.
The vehicle crosses several transponders. After the first transponder a position
cannot yet be calculated. After the second transponder the position and head-
ing can be calculated. After the third transponder the position is confirmed and
the accuracy is set to a good value provided the position of the third transpon-
der corresponds to the position of the previous ones.
If the vehicle is steered by a driver (manual mode) it sometimes happens that the tran-
sponders are not crossed. This results in a decreasing accuracy of the odometry. As
the system has not been switched off the only remaining possibility for initialization is
number 2.
2.3.1.3
Transponder List
The transponder list is a CSV file (separated by a semicolon). It can be created and
edited with Excel or other programs. The steering controller can import and export this
list with the X-modem protocol using a terminal program. Additionally the list can be
displayed from the steering controller with the terminal program.
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;031;6891;9000;127;127;1
These values have the following meaning for the steering controller: