National Instruments NI-Motion - Manual (Page 134)

Chapter 10 Electronic Gearing and Camming
NI-Motion User Manual 10-12 ni.com
Camming Table
When a camming operation is active, the slave axis follows a profile that is
established using a list of master and slave positions pairs, called the
camming table. Refer to Table 10-1 for an example of a camming table.
Figure 10-9 shows that, in the welding example defined in Figure 10-7, the
conveyor belt is moving at 1,000 counts/s and the parts to be welded are
6,000 counts apart. To weld the part, the welding point must follow the part
down the conveyor belt for 2 seconds.
Figure 10-9. Welding Application Time and Speed Constraints
In this welding application, the slave axis must follow the part with the
same velocity as the conveyor belt while welding is in progress. Because it
takes two seconds to weld each part, the welding point and conveyor belt
have both moved 2,000 counts by the time the welding is complete. This
part of the welding application creates the first move segment.
For the second move segment, the welding point must return to its original
position so that it can weld the next part on the conveyor belt. To move the
welding point to its original position at the same time that the next part is
in the correct position on the conveyor belt, the welding point must travel
Conveyor belt speed
(1000 counts/s)
Time to dwell
during welding
(2 seconds)
6,000
counts
between
welding
spots