Aerotech UNIDEX 600 Series, User Manual

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U600 User’s Guide AerTune
Version 1.4
Aerotech, Inc.
5-5
parameter varies the damping effect of the servo loop. The Ki parameter varies the
integral gain of the servo loop for increasing stiffness, while in position, and improves
settling time. The VGain parameter minimizes the position error during constant velocity
in analog tachometer based systems and torque mode systems with large frictional loads.
The Vff parameter enables velocity feedforward for the axis minimizing position error
during constant velocity. The AffGain parameter provides acceleration feedforward for
the axis, which minimizes position error during acceleration and deceleration.
5.3.1. Step Move Parameters
The distance field is the number of machine counts that the axis will move when the
Step+ or Step– (or auto, cycle +/-) buttons are pressed. Speed is the velocity in machine
counts/second that the axis will move at. We recommend using sinusoidal rate based accel
and decel modes.
The mode (rate/time) for G0/Asynchronous motion, generated by AerTune, is determined
by each axes ACCELMODE/DECELMODE axis parameters, which also select
linear/sinusoidal profiles. The appropriate axis parameter (shown below) will then
determine the acceleration/deceleration of the axes.
Acceleration Axis Parameters Deceleration Axis Parameters
ACCELMODE DECELMODE
ACCEL (time) DECEL (time)
ACCELRATE DECELRATE
Figure 5-3. Step Move Parameters