We surmise the noisy loops are because we need fresh transfer functions because we shifted the plant:  We lowered the HEPI 3+ mm as well as moved a mm laterally.  This displaces the SEI Expansion Bellows (Vacuum Seal) and changes the plant resistances.  Another reason for the noisy loops, y mainly, may be due to the cleanroom sheets impacting the y motion.  Jim also thinks the locked ISI may be altering the plant too much.

I ran Local Range of Motion tests on HEPI and have no problem achieving 0.8mm.  The linearity test however looks strange which actually displaces about half as much as the ROM test--see attached.  The Verticals look really good but the horizontals suggest some issues.  There are no historic linearity plots from ITMX to compare, too bad.  My strongest suspision is the cleanroom and I'll stick with that until it can be ruled out before I think about changing HEPI Parker Valves.

Here is the Matlab output from the Range of Motion Test:

There is a range of motion of 0.0008M on

ans =

    'Neg H1'
    'Pos H1'
    'Neg H2'
    'Pos H2'
    'Neg H3'
    'Pos H3'
    'Neg H4'
    'Pos H4'
    'Neg V1'
    'Pos V1'
    'Neg V2'
    'Pos V2'
    'Neg V3'
    'Pos V3'
    'Neg V4'
    'Pos V4'

Short Range of motion on:

ans =

   Empty cell array: 0-by-1