THORLABS Kinesis PFM450E, Руководство пользователя

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PFM450E Piezo Focus Mount and Controller
The following section describes details a typical tuning procedure
1) Measure and record the objective mass.
2) Fit the PFM450 to the microscope - see Section 3.3.
3) Fit the objective to the microscope - see Section 3.4.
4) Switch on the controller and leave to warm up for at least 30 minutes.
5) Run Kinesis and switch to Open Loop mode.
6) In the Settings panel, ensure that the Notch Filter 1, Notch Filter 2 and Derivative
LP Cut OFF are all ticked as "Enabled" - see Section 5.2.3.
7) Set the notch filter central frequency as explained in Section 5.2.3.
8) Set the PID parameters as explained in Section 5.2.3.
9) Switch to closed loop mode.
10)The stability of position display should be better than ± 0.02 µm with a stable
microscope system. While monitoring the position display on the GUI, reduce P, I
and D parameters one at a time, by 10% steps to optimise display jittering.
11)To ensure the settling time is optimised, increase P, I and D with 10% increments
until position display indicates a large ringing effect, in the range of microns.
Consider this point as threshold for stability.
12)Reduce the threshold values by 10% to 20%, to ensure a safe margin and a fast
response is guaranteed.
13)In case of a high level ringing, e.g. amplitude in order of 10s of microns (especially
if it is audible), switch to Open Loop mode, set parameters as explained above,
then switch back to Closed Loop. In such situations, it is advisable to have starting
P, I and D parameter values well below the last set of values that caused ringing.
4.5 Limitations on the Displayed Position Values
The controller can report small negative position values and the software can display
these; however negative position values below approximately 4% of the full travel
range (i.e. more negative than -32 um for a 800 um stage / -18 um for a 450 um stage)
might be clipped and therefore incorrect. Position values above the maximum travel
range are clipped to the maximum travel. In other words, the position display is
clipped to -4% to +100% of the maximum travel range.