Differences between revisions 3 and 6 (spanning 3 versions)
⇤ ← Revision 3 as of 2017-12-27 06:58:24 →
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Editor: RanaadhikariATligoDOTorg
Comment:
← Revision 6 as of 2018-01-04 02:24:27 → ⇥
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Editor: KojiaraiATligoDOTorg
Comment:
Deletions are marked like this. Additions are marked like this.
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     * What about just using 3 little coil springs to mount the breadboard from underneath rather than use blades? Then its more like an extra layer of the stack.
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     * Requirement      * Requirement: 30x reduction for f = 10-100 Hz
     * pendular modes should be 0.2-0.45 Hz or 1.5-2.5 Hz to avoid SOS resonances.
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  * Active VS Passive approach
    * Active
       * Pros
         * ...
       * Cons
         * ...

    * Passive
       * Pros
         * ...
       * Cons
         * ...

Optical Platform Suspension

Each in-vacuum optical table for the 40 m test masses is an optical breadboard with a diameter of 38 inches. We plan to place a single stage suspended breadboard on top of this existing table to get 1 additional stage of seismic isolation. We will need 4 of these to cover each test mass.

  • VOPO style suspension
    • Attach a structure (poles or a frame) on the existing breadboard
    • The structure supports vertical blades
    • Wires are attached on the vertical blades
    • A breadboard is suspended from the vertical blades
  • Breadboard
    • Thickness
    • Internal resonances: modes/frequencies
  • Blade spring
    • Load weight (total weight of the load, max load)
    • constrained layer damping of blade modes ?
    • What about just using 3 little coil springs to mount the breadboard from underneath rather than use blades? Then its more like an extra layer of the stack.
  • Counter balance
  • Vibration isolation
    • Requirement: 30x reduction for f = 10-100 Hz
    • pendular modes should be 0.2-0.45 Hz or 1.5-2.5 Hz to avoid SOS resonances.
  • Active control
    • Sensor (What, how many, how sensitive, range, noise)
    • Actuators (Coil Magnet, requirement, strength, Vertical, Horizontal )
    • Electronics (Feedthru)
    • Control system
    • does it need to be active or can we use resonant eddy current damping?
  • Utility structures
    • EQ stops
    • Safety (Blades/Wires)
  • Active VS Passive approach
    • Active
      • Pros
        • ...
      • Cons
        • ...
    • Passive
      • Pros
        • ...
      • Cons
        • ...

Optical_Platform_Suspension (last edited 2018-01-04 02:24:27 by KojiaraiATligoDOTorg)