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Entry  Mon Aug 30 17:49:43 2021, Paco, Summary, LSC, XARM POX OLTF XARM_POX_OLTF.pdfXARM_POX_Coh.pdf
    Reply  Tue Aug 31 14:55:24 2021, rana, Summary, LSC, XARM POX OLTF 
Message ID: 16303     Entry time: Mon Aug 30 17:49:43 2021     Reply to this: 16304
Author: Paco 
Type: Summary 
Category: LSC 
Subject: XARM POX OLTF 

Used diaggui to get OLTF in preparation for optimal system identification / calibration. The excitation was injected at the control point of the XARM loop C1:LSC-XARM_EXC. Attachment 1 shows the TF (red scatter) taken from 35 Hz to 2.3 kHz with 201 points. The swept sine excitation had an envelope amplitude of 50 counts at 35 Hz, 0.2 counts at 100 Hz, and 0.2 at 200 Hz. In purple continous line, the model for the OLTF using all the digital control filters as well as a simple 1 degree of freedom plant (single pole at 0.99 Hz) is overlaid. Note the disagreement of the OLTF "model" at higher frequencies which we may be able to improve upon using vector fitting.

Attachment 2 shows the coherence (part of this initial measurement was to identify an appropriately large frequency range where the coherence is good before we script it).

Attachment 1: XARM_POX_OLTF.pdf  37 kB  Uploaded Mon Aug 30 19:00:27 2021  | Hide | Hide all
XARM_POX_OLTF.pdf
Attachment 2: XARM_POX_Coh.pdf  18 kB  Uploaded Mon Aug 30 19:00:34 2021  | Hide | Hide all
XARM_POX_Coh.pdf
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