Servo vibration

Hello, we have one problem with the servo vibration.
The input-scale in the ini file is 250, The impulse to pc is comming from Heidenhain ROD424.

1rev = 250 counts and 0,2rev/mm
50counts / 1mm

this is axis0 exemple in the inifile:

# First axis
[AXIS_0]

TYPE = LINEAR
UNITS = mm
HOME = 0.000
MAX_VELOCITY = 1.0
MAX_ACCELERATION = 4.0
BACKLASH = 0.000
#INPUT_SCALE = 81920
INPUT_SCALE = 250
OUTPUT_SCALE = 1
OUTPUT_OFFSET = 0
MIN_LIMIT = -100.0
MAX_LIMIT = 100.0
FERROR = 100.000
#MIN_FERROR = 0.002
HOME_OFFSET = 0.10
HOME_SEARCH_VEL = 0.10
HOME_LATCH_VEL = -0.01
HOME_USE_INDEX = YES
HOME_IGNORE_LIMITS = YES
MAX_OUTPUT = 10.0
# PID tuning params
DEADBAND = 0.000015
P = 100.0
I = 0.000
D = 0.000
FF0 = 0.000
FF1 = 0.000
FF2 = 0.0
BIAS = 0.000

you have an example of what should be there in the PID and FF

There are no fixed PID numbers as they must always be adjusted for each system
this is called "tuning"

How tuning is done depends on your drive type (the motor drive) that is whether it is a:

1. Velocity mode drive (drive with local velocity feedback loop often with tachometer)

2. Torque mode drive (current mode)

3. Simple HBridge (voltage mode)

If you can provide this information it would be easier to help

We have +/-10V and the impulse is comming from the servomotor-encoder

OK so that means a velocity or torque mode drive
Do you have any idea which it is?

Is there a tachometer on the motor?
Do you have the motor drive part number?
Does the encoder signal go to the drive?

we send +/- 10V to the servomotor and the encoder singnal is comming back from Heidenhain ROD424.
The Heidenhain ROD424 is on the servomotor and from this comming the singnal to pc.
The Servo have nothing tachometer.
The +/-10V going to one Magnetventil and the magnetventil controls the hydraulicmotor.
The Axis drive Hydraulic and the hydraulicmotor have the encoder and this encode send the singnal to pc.

OK well on the basis of not understanding your hardware at all I would try this

start with a low P term (say 1) and increase it slowly till you get oscillation (vibration)
Then start adding D term until the vibrations cease (to much will cause vibrations to start again)

Can you provide a HALScope plot of the vibrations?

I think if the encoder have 250 pulses/rev and 1 rev is 5mm then INPUT_SCALE should be 50 not 250 (250 is equal to 1 rev or 5 mm, 50 is equal to 1/5 rev or 1 mm).
Also DEADBAND should be equal to 1, 1.5, 2 o 3 encoder counts (i mean 1/50, 1.5/50, 2/50 or 3/50 mm).

OK, Thanks.
I'm back on freday again.

Steffen