J. Kissel, (for K. Kawabe, K. Izumi, and T. Sadecki)

Team TMS + Travis ventured down to the y-end this morning in hopes to discover some obvious source of rubbing, which I'd reported a few days ago (see LHO aLOG 5768). Unfortunately, they didn't find anything. They did adjust the alignment/centering on a few of the BOSEMs (they didn't say which), because only because they looked suspicious. I've taken a new set of transfer functions, and I see little to no change. The best "improvement" is that the three Transverse modes look more like the model -- but the model still comes with many grains of big'ol kosher salt, and the high-frequency noise (for this DOF) looks much worse. I'll continue to push forward on a "new" damping loop design (more likely I'll just model the damping with the measured TFs, asses where things are going unstable, and move around some poles or zeros if need be), in parallel with further investigations of rubbing.

Note: Mark made some improvements to the model this morning -- mostly related to making sure the coordinate system is as expected by the model (it's a whole confusing mess between the SolidWorks XYZ, the Dynamical Model's XYZ, and the Euler Control Basis -- especially since the top mass is the same as a QUAD top mass but rotated 90 [deg] with respect to Dynamical Model expects. Not to mention left-handed vs. right-handed TMTSs). We *think* we've got them correct at the moment, but the only way we can be sure is by opening up SolidWorks and checking (where Mark and I only have the eDrawings).