Table of Contents
Advertisement
DL Stage Series
3.5
Dynamic Characteristics
Dynamic response of the stage depends on two parameters:
• The force delivered by the motor
• The total moving mass including carriage mass and payload
Newport's DL Controller includes four parameters allowing dynamic
control optimization of the stage:
• Scaling Force
• Force Limit
• Carriage Mass
• Payload Mass
Although the three parameters are set in the factory perstage, the fourth
(Payload Mass) must be adjusted by the user. Refer to the "FM" command
of the Newport DL Controller user's manual.
3.5.1
Description of Parameters
The DL Controller/driver "ScalingForce" parameter is used by the
controller to scale the output current. It indicates the theoretical
maximum force (friction not taken in account) of the DL carriage with the
controller full scale current (See Controller Manual).
The DL Controller/driver "ForceLimit" parameter indicates the maximum
force of the DL stage carriage limited by current saturation to avoid stage
damage.
Then, stage carriage acceleration can be calculated using the following
formula:
MaxAccelaration =
See chapter 3.4.3 acceleration/Load graph.
• Due to its linear motor and rails, DL stage Friction Constant is only 4 N.
• Carriage Mass is 0.85 kg.
3.5.2
Stages Adjustement Proposal in Function of the Load
In order to improve and have better driving performances, it is advisable
to change the control parameters according to the load. All the stages are
delivered with a crossover frequency of 70 Hz. You can change the
parameters KP, KI, KD, FD, FL and FMP in the controller terminal. Please
see the following table:
Customer payload from
High (2 kg ) to low (0 kg)
FMP command
Response Time
Crossover Frequency (Hz)
Derivative cut off frequency (FD)
PID 2nd Order low pass filter (FI)
High-Performance Delay Line Stages
ForceLimit - Friction Constant
Carriage Mass + Payload mass
High
Slow
55
KP
19,000
KI
2,000,000
KD
350
100
4,000
5
Medium
Low
Medium
Fast
70
80
31,000
48,000
3,500,000
5,000,000
420
500
140
150
4,000
4,000
EDH0391En1031 — 03/18
Hide quick links:
Advertisement
Table of Contents
