Metronix ARS 2320, Руководство по эксплуатации продукта

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Function overview Page 62
Product Manual „Servo drives ARS 2320, ARS 2340, ARS 2320W, ARS 2360W“ Version 8.0
5.3.2 Relative positioning
In the case of relative positioning, the target position is added to the current position. Since no fixed
zero is required, referencing is not compulsory. It does, however, make sense in many cases, in order
to bring the drive to a defined position.
Adding of relative positioning allows for example endless positioning in one direction for a trimming
unit or a conveyor belt (incremental dimension).
5.3.3 Absolute positioning
The target position is approached independent of the current position. In order to execute an absolute
positioning we recommend prior referencing of the drive. In the case of absolute positioning the target
position is a fixed (absolute) position referred to the zero or reference point.
5.3.4 Driving profile generator
Driving profiles are categorized in time-optimal and jerk-limited positioning. In the case of time-optimal
positioning the maximum set acceleration is used for starting and braking. The drive approaches the
target in the shortest time possible, the velocity profile is trapezoidal, and the acceleration profile is
block-shaped.
In the case of jerk-limited positioning the acceleration profile is trapezoidal and the velocity profile is
therefore of third order. Since the acceleration changes continuously, the drive is extremely gentle on
the mechanics.
a(t) a(t) a(t)
t t t
v(t)
t
v(t)
t
v(t)
t
time-optimal jerk-limited jerk-limited
Figure 8: ARS 2300 servo drive driving profiles