Sheila, Elenna, Caroline, Julia

We tested and reconfigured the DRMI ASC, and now we can run all of the DRMI ASC!

I trended the POP A offset yesterday to determine what the new values should be based on the alignment of the PRM once we are in full lock. I set those so we can use the PRC1 ASC loop (attachment 1 and attachment 2).

Then, we sat with DRMI locked and Sheila and I tried moving around PR2, IM4 and PRM to check if the error signals made sense. PRM uses POP A QPD, IM4 and PR2 use REFL A and B 9 MHz signals. We found that the PR2 and IM4 error signals seemed flipped, so we checked all of the REFL WFS signals and even thge POPX signals to see what might be the best new sensing matrix. Eventually, we chose to remain on REFL 9 I, but we flipped the sensing.

We were able to engage all the SRC ASC, except that after a minute or two og engagement, we saw an oscillation in the SRC signals. We eventually turned down the SRC1 P and Y gains, and the SRC2 P gain.

I tried moving the PRM to confirm the PRC1 error signal was ok, and I found that the pitch offset I chose was good, but the yaw offset was not good. So instead I moved the PRM yaw to maximize the buildups, and then reset the the POP A yaw offset (attachment 3).

Then, Sheila and I tried engaging the PRC2 and INP1 yaw ASC, but used the wrong sign for PRC2 Y and caused the DRMI lockloss. Luckily, we quickly recovered, and changed the sign and reengaged. We followed a similar procedure for the pitch ASC, but I stepped PR2 a few times to ensure the sign of the input matrix was correct.

We were then able to engage all the DRMI ASC, using lower SRC1 and SRC2 gains to prevent ringing. Sheila updated the ISC DRMI guardian to use these new input matrix values.

Except for some overall magnitude, the DRMI INP1 and PRC2 sensing has had this change in both pitch and yaw:

old sensing: INP1 = + REFL 9I A - REFL 9I B and PRC2 = +REFL 9I A + REFL 9I B

new sensing: INP1 = +REFL 9I A + REFL 9I B and PRC2 = -REFL 9I A + REFL 9I B

With the ASC engaged, we were able to raise the SRC1 pitch and yaw gains back to their nominal values (updated again in guardian). The SRC2 P loop still has a lower gain.