June 23: Aborted "Baseline" & TBF Temperature Change Test

• Configuration:

  • ACS: Fully Assembled
  • Mounting: In TBF/Diamond with New Linear Bearing B-Latch
  • Cooling: Chillers
  • Optical Source: HRC Coronagraph Spot with Backlight; WFC RAS/Cal
  • Starting Temp: Ambient at Start of Day
  • Add'l Sensors: LVDTs to Monitor Motion of Bench Relative to Enclosure

• Figures:

  • HRC stability track: ( GIF, Postscript )
  • WFC stability track: ( GIF, Postscript )
  • Metrology thermal set A: ( HTML, Excel, notes )
  • Metrology thermal set B: ( HTML, Excel, notes )
  • LVDT setup: ( HTML )
  • LVDT data: ( PDF )

• Results:

  • Had Planned to Run Long Duration Baseline for Comparison to RASHOMS Results
    • WFC Over-Temp Forced WFC TECs to be Turned Off; Baseline Aborted
  • Temp Change of TBF Bottom Support Post (20 to 30 to 20C) Caused WFC & HRC Motion
  • Temp Change of +V2 Support Post (20 to 30 to 20C) Caused WFC & HRC Motion
  • During Temp Changes B-Latch Load Cell Measured Changing Load (~30lb) and LVDTs Measured Motion of Enclosure & Bench Relative to TBF

• Conclusion:

  • TBF Temp Changes Causes TBF Length Change Causes Load Change Causes Enclosure/Bench Motion
    • Y-Fitting "Stiction" Prevents Verification of Proper B-Latch Motion