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
Each row of this table represents one support point. The first column specifies to which seg-
ment a specific support point belongs. In the second column the support point is addressed
within its segment. Columns 3 and 4 contain the X and Y co-ordinates of the support point
in mm or in 1/10mm (according to the adjustment of the CAD program and the steering
controller, see Configuration Main –> Resolution Segment Points in section 4.3.1 on page
57). Columns 5 and 6 contain velocity data in mm/s. There are two velocities because on
the one hand a connecting segment could exist, or the vehicle is to be stopped at the end
of the segment. Therefore, for a final segment (target) or when the vehicle changes direc-
tion column 5 is automatically selected. If a connecting segment follows column 6 is select-
ed.
The velocities are interpolated linearly depending on the position between the support
points so that a continual velocity profile is created. Only in the following cases the speed
will be set to 0 by the Control Unit:
–
At the end of the target segment.
–
When the direction of travel changes.
–
If an error occurs.
Tip
Use 1 as the final speed since 0 might result in the vehicle stopping before the segment
ends.
Figure 13
Example for congruent segments
The vehicle always moves continuously
through the segment in the direction of
the support points (from the start of a seg-
ment to its end). This means that when the
vehicle is first to be driven in one direction
on a segment and then to be reversed (e.g.
when docking onto and undocking a
ramp) there must be two segments for the
same part of the track.
Column 7 contains the 32 bit attribute. The
attribute is sub-divided into 16 higher and
16 lower bits. The lower bits refer to inter-
nal functions of the navigation controller.
Table 53 on page 144 shows the meaning of those bits. The16 higher bits – except for the
two most significant bits – are freely available and are passed to the vehicle control unit, e.g.
via CAN Bus, see Table 28 on page 106.
2.5.2.2 The Segment Search
When vehicle tracking is initialized, only the position of the vehicle is known. To identify the
currently drivable segments and transmit them to the central control unit, a segment search
can be carried out (as described in the following section this process usually runs automat-
ically in the background). During the segment search, the navigation controller tests all the
segments stored for drivability. The segment search can take several seconds depending on
Vehicle
Ramp
Segment 1
Segment 4
Segment 2 Segment 3
