Fuji Electric ALPHA7, User Manual

Page: 115 / 662

CHAPTER 2 WIRING
2-68
Description of I/O Signals
2
Anti resonance frequency selection 0: Sequence input signal (Reference value 57)
Anti resonance frequency selection 1: Sequence input signal (Reference value 58)
Select the anti resonance frequency, which is a vibration suppressing control function.
 Function
In a spring characteristic structure such as the robot arm and transfer machine, vibration is caused
at the end of the workpiece upon sudden acceleration or deceleration of the motor. Vibration
suppressing control aims at suppression of vibration of the workpiece in such a system, thereby
realizing positioning at a shorter cycle time.
Four points through combination of anti resonance frequency selection 0 and anti resonance
frequency selection 1 can be specified.
The anti resonance point may vary according to the length of the arm and the weight of the load.
Selection of the anti resonance frequency is shown in the table below.
Anti resonance
frequency selection 1
Anti resonance
frequency selection 0
Vibration suppressing
resonance frequency
Vibration suppressing
workpiece inertia ratio
OFF OFF PA1_78 PA1_79
OFF ON PA1_80 PA1_81
ON OFF PA1_82 PA1_83
ON ON PA1_84 PA1_85
 Parameter setting
To assign the anti resonance frequency selection 0 or anti resonance frequency selection 1 to a
sequence input terminal, specify the corresponding value ("57" or "58") to the input terminal
function setting parameter.
These signals are handled to be always turned off if they are not assigned to sequence input
signals.
In this case, PA1_78 (vibration suppressing resonance frequency 0) is always enabled.
To disable the anti resonance frequency, set the anti resonance frequency at 300.0Hz.
Because in-cycle switching of the anti resonance frequency causes a shock, switch during
stoppage without fail.
In addition, it is recommended to use PA1_52 (low-pass filter (for S-curve) time constant) in
parallel.
(a) (b) (c)