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Entry  Sat Nov 26 02:15:42 2011, Mirko, Update, SUS, Not adaptive, still cool PendulumQ0.1HzWithElip2comma5HzLpWfsOnCorrectedShape.pdfVirtualPendulumFilterShape.pdfSetupVirtualPendulumV2.png
    Reply  Thu Dec 1 03:27:39 2011, Mirko, Update, SUS, Not adaptive, still cool 
Message ID: 6014     Entry time: Sat Nov 26 02:15:42 2011     Reply to this: 6057
Author: Mirko 
Type: Update 
Category: SUS 
Subject: Not adaptive, still cool 

[Rana, Mirko]

I tried out the virtual pendulum idea today. The idea is to compensate the physical pendulum via the control system, and then add a virtual pendulum formed in the control system. We know the actuator TF from p. 5900 and apply its inverse to the C1:SUS-MC?_SUSPOS filters. Also we add an pendulum Q=3 with a resonance frequency of 0.1Hz to the POS control loops.

The result is pretty awesome!

1. Black: Standard config. Wfs on. New Cheby filter in place ( p. 6031 )
2. Red: With virtual pendulum. Extra eliptic LP filter @ 2.5Hz

PendulumQ0.1HzWithElip2comma5HzLpWfsOnCorrectedShape.pdf

Filter shape:

VirtualPendulumFilterShape.pdf

This is stable for 5-10minutes, at which point it falls out of lock, swinging in yaw.

 

 

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