THORLABS LNR502E, Руководство пользователя

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LNR502E Encoded Long Travel, Linear Stage with Stepper Motor Actuator
2) Select the Advanced tab.
Fig. 4.5 Settings - Advanced tab
3) In the PID Loop Mode field, select Closed Loop.
4) Encoder feedback is now enabled.
When Closed Loop is selected, the motion processor within the controller uses a position control loop to determine the motor
command output. The purpose of the position loop is to match the actual motor position and the demanded position. This is
achieved by comparing the demanded position with the actual position to create a position error, which is then passed through
a digital PID-type filter. The filtered value is the motor command output.
The default PID parameters should be sufficient for most applications, but these can be fine tuned to improve performance as
required by creating Custom settings - see the manual for the associated controller and also the Kinesis helpfile for further
information on creating custom settings.
The parameters on the settings panel are described as follws:
Proportional Gain
- Together with the Integral and Differential, these terms determine the system response characteristics and
accept values in the range 0 to 16777216.
Integral Gain - Together with the Proportional and Differential, these terms determine the system response characteristics and
accept values in the range 0 to 16777216.
Differential Gain
- Together with the Proportional and Integral, these terms determine the system response characteristics and
accept values in the range 0 to 16777216.
Integral Limit - This parameter is used to cap the value of the PID loop to prevent runaway at the output. It accepts values in
the range 0 to 16777216. If set to 0 then the output of the PID loop is ignored.
Tolerance
- Value below which the output of PID generator is effectively deemed to be zero to avoid continual cycle about set
point
Encoder Coefficient - This is a conversion factor from Encoder counts to microsteps for the specific stage and controller being
used. For the BSC series controllers and LNR50SE stage, the value is 4292282941. If set to 0, then no encoder is fitted to the
stage.