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Entry  Sat Aug 13 15:47:47 2011, Nicole, Summary, SUS, TT Optimization Curves magstrength1.jpgdampermass.jpgresfreq.jpg
    Reply  Sat Aug 13 19:08:01 2011, Koji, Summary, SUS, TT Optimization Curves 
       Reply  Sat Aug 13 21:15:47 2011, Nicole, Summary, SUS, TT Optimization Curves 
          Reply  Sat Aug 13 21:48:17 2011, Koji, Summary, SUS, TT Optimization Curves 
             Reply  Sun Aug 14 00:26:51 2011, Nicole, Summary, SUS, TT Optimization Curves 
                Reply  Sun Aug 14 13:57:52 2011, Nicole, Summary, SUS, TT Optimization Curves FLEX_exp_mod_comp.jpg
Message ID: 5223     Entry time: Sat Aug 13 15:47:47 2011     Reply to this: 5224
Author: Nicole 
Type: Summary 
Category: SUS 
Subject: TT Optimization Curves 

Using my Matlab model of the flexibly-supported eddy current damping system, I have changed parameters to see if/how the TTs can be optimized in isolation. As I found earlier, posted in my bode plot entry, there is only a limited region where the flexibly-supported system provides better isolation than the rigidly-supported system.

 

Here is what I have found, where \gamma is the scale factor of the magnetic strength (proportional to magnetic strength), \beta is the scale factor of the current damper mass (estimated by attempting to fit my model to the experimental data), and \alpha is the scale factor of the current resonant frequency of the dampers.

magstrength1.jpgdampermass.jpg resfreq.jpg

 

Here are my commentaries on these plots. If you have any commentaries, it would be very helpful, as I would like to incorporate this information in my powerpoint presentation.

It seems as if the TT suspensions are already optimized?

It may be difficult to lower the resonant frequency of the dampers because that would mean changing the lengths of the EDC suspensions). Also, it appears that a rather drastic reduction (at most 0.6*current EDC resonant frequency --> reduction from about 10 Hz to 6 Hz or less) is required . Using the calculation that the resonant frequency is sqrt(g/length), for my single-suspended EDC model, this means increasing the wire length to nearly 3 x its current value. I'm not sure how this would translate to four EDCs...

The amplification at resonance caused by increasing the magnet strength almost offsets the isolation benefits of increasing magnet strength. From my modeling, it appears that the magnet strength may be very close (if not already at) isolation optimization.

 

Lowering the mass to 0.2 the current mass may be impractical. It seems as if the benefits of lowering the mass only occur when the mass is reduced by a factor of 0.2 (maybe 0.4)

 

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