Arnaud, Sheila, Kiwamu,
We copied the plant inversion filters from ETMX UIM to ETMY, and ran a transfer function to test it.  The results are saved in /ligo/home/sheila.dwyer/ALS/HIFOXY/Y_UIM.xml

I imported the measurement into foton, and compared it to the low pass blend (which was on when I took the measurement) and a pedulum at 1 Hz with a Q of 1, which is what our plant is supposed to be with the inversion.  They match pretty well, screenshot attached.  Since our inversion of the ETMX top mass and the UIm match for the resonances that are common, we just copied the ETMX top mass plant inversion to ETMY and decided to try this out.

Also, we tried using an offset for the ESD drives, which should give us a bit more range.  With the bias at 125000cnts, I added an offset of -51777 counts to each of the quadrants, following the math in T1400321.  At 4 Hz, we measured a factor of 1.77 more gain , at 6 Hz 1.6 more gain.