Yesterday, filters  were installed on ETMY which is now in the same configuration as ETMX. This includes top mass length to angle decoupling, and angular plant inversion at all stages to facilitate loop design for wfs and/or oplev.

When driving in pitch through the drivealign matrix with the "invP2P" filter on, the transfer function from the drive to the test mass should give a single pendulum with a resonance at 0.45Hz, and a Q of 3.
When driving in yaw, the transfer function should be similar, but with a resonance at 0.6Hz.
Note : all the gains are set to 1

The length to angle decoupling for pitch and yaw from the top mass has been roughly tested by sending a longitudinal excitation at 0.5Hz and looking at the oplev signal. I didn't quantify it yet, but it seemed to reduce the angular motion when turning the filters on.
The two filters L2P1 and L2Y1 installed at the top mass should be used with a gain of -1

Left to do for EX and EY is length to angle decoupling on UIM and PUM.