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
This list is sent back to the vehicle control. The vehicle control may then react by placing a
new segment in the FIFO.
This way more than 8 segments can be traveled in a row. In order for the segments to be
concatenated the end position of a segment must be the start position of the next segment.
ATTENTION!
In order to prevent the steering controller from loading a segment currently being changed
by the Vehicle PLC (a cycle consisting of "reading the list" to "list written" can easily take one
second), never the next, but always the next but one segment (FIFO- Register number 2) or
higher segments should be changed!
2.5.2.4 Transmission of Segmente
Usually the segments will be transmitted via the CAN bus or Feldbus. For testing purposes
the segments can be entered in the menu Parameter Test. For more detailed information
see section 4.10 on page 83 and chapter 5 on page 86.
The navigation controller includes the segments in the Can box Path Data (Target). The
structure of the box is described in Table 36 on page 114. This box only contains one ele-
ment of the buffer, namely „Number of segment (LowByte)“ and „Number of Segment
(HighByte)“. The segment numbers will be transferred as Unsigned int (16 bit).
To place the segment correctly into the FIFO, the register number will be transferred as well
(Position of segment number in table). The navigation controller will be called up every 10
ms. Therefore the transmission of the list takes at least 8 x 10ms = 80 ms. This list always
Before
Example:
Segment No. 33 completed
After
FIFO
Segment
FIFO
Segment
0
33
0
10
1
10
1
17
2
17
2
105
3
105
3
65535
4
65535
4
65535
5
65535
5
65535
6
65535
6
65535
7
65535
7
65535
Table 3
Example: Shifting of segments in the FIFO
Before
After
FIFO
Segment
FIFO
Segment
0
10
Segment No. 55 added
0
10
1
17
1
17
2
105
2
105
3
65535
3
55
4
65535
4
65535
5
65535
5
65535
6
65535
6
65535
7
65535
7
65535
Table 4
Example: Adding new segments to the FIFO