Earlier today, with Ryan's encouragement, I turned on more of the I/ETMY isolation loops. Currently these 2 ISI's are running a configuration like LLO's, with all DOFs engaged on St1 and X,Y,Z,RZ running on St2. The St1 RZ loop is running a high (750mhz) blend with no T240. St2 is running the same 250mhz blend on Z and RZ as it was previously running on X and Y. The Stage Guardians for these two chambers have also been modified to turn on these loops, in case we have some traumatic event.
FF is now running on all test mass chambers as well with X&Y running on ETMY, Y on ITMY and X on E/ITMX.
Turning on the extra loops seems to mostly reduce the suspension point motion, although vertical motion looks to be a bit worse at .1-.3 hz. Attached plots are ETMX and ETMY suspension point motions, respectively. ETMX was running the normal LHO configuration, with no RZ loops on, only X&Y on stage 2, LLO blends plus ST0-1 FF running on the Y degree of freedom. ETMY was running a mostly LLO configuration, with all loops on St1, LLO blends plus the Start blend on RZ, St2 with all loops running except RX & RY, with St0-1 FF running on X & Y.
Plots of the two high blend filters we have. CPS Signal is common to both, blue is inertial (L4C only, no T240 in that blend) part of the Start filter, green and brown are inertial parts of the T750 filter.