The microscale may be dead. I think the bearing is sticking (for the second time). There can only be one solution to a mechanical problem... software! I tried to work around it in some interesting ways.
  • Adjust the indicator flag to be more like the original article
  • Adjust the flag most of the way to normal
  • Attempt to calculate the mass as a function of both the current force and the current error
  • Adjust the gain so that it moves faster
  • Adjust the gain so it moves more slowly
  • Adjust the gain so it moves WAY more slowly
  • Put the gain back where it was
  • Add 2 to the gain instead of 1
  • Undo
  • Stop averaging the last two error readings
  • Undo
  • On Even seconds, reduce the force by 5mg to break the friction
  • 10mg?
  • 15mg?
  • Undo back to 10mg
  • When seconds MOD 4 == 0, reduce the force, ==1 and ==2 go back to the regular force, ==3 actually try to balance
  • Same, but with MOD 5
  • Same, but break the 5 second cycle into 1,2,2 instead of 1,3,1 (Fake, recover, balance)
  • reduce the force by 20mg
So, after all that (half of which is in the SVN), It is repeatable to within +/- 0.3 mg (when it stabilizes), or it will flail around wildly +/- 70mg. The only difference between the two states is when you put the sample on the scale.

Possible "improvements"/Next Steps(that don't involve the 2kW heaters from the last UW project, just to see if they still can melt aluminum in 10 minutes)
  • replace the galvanometer
  • add springs to support the flag (stabilize)
  • make the moving parts lighter (reduces accuracy - HA!)
  • Realize that Erica can manually take the data faster than I can fix the scale
  • Offer to set up webcam and OCR the regular scale into data
  • Offer to write AHK script that will show pictures from the Nikon of the regular scale, so data entry is faster

(for those keeping track, Finished_Projects is now back to nil,m not counting FIRST)

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