2 more complex ptp motions – ElmoMC SimplIQ Digital Servo Drives-Bell Command Reference User Manual
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1000
2000
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50
100
S peed
A cceleration
(A C )
C onstant speed
(S P )
D eceleration
(D C )
P osition
Figure 6-2: Trapezoidal speed profile
With shorter movement, the deceleration begins before the speed limit is reached, so that
the SP speed limit is not effective. This situation is depicted in the following figure:
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-500
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A C
D C
Time (sec)
Time (sec)
S peed
P osition
Figure 6-3: Triangular speed profile
6.1.4.2 More Complex PTP Motions
PTP motions may be initiated any time, using the PA command, but not necessarily from
a stationary state. The PTP decisions, made every position control cycle, are described in
the following flowchart. All parameters in the flowchart — including AC, DC, SP and
position target — are updated by a BG command, or by its hardware-activated
equivalent.
SimplIQ for Steppers Application Note
The Position Reference Generator
MAN-STECR (Ver. 1.1)
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