Arnaud, Oli

As part of our BBSS alignment and investigation, I used /ligo/svncommon/SusSVN/sus/trunk/BBSScomparetripleparams.m to look at the DC values of our current model when actuating at M1 and reading out at M3. 

I made a few edits to comparetripleparams.m in order to allow me to do this easily, and I've committed those changes as r13039.

The plots (P, Y) show that the DC value for M1 P to M3 P is 0.029 rad/Nm and M1 Y to M3 Y is 0.129 rad/Nm. These plots can be found in /ligo/svncommon/SusSVN/sus/trunk/BBSS/Common/Results/comparetripleparams/comparetripleparams/2026-06-23_M1toM3Model/triplemodelcomp_2026-06-23_M1toM3Model_M1toM3.pdf r13040.

We then converted into cts/N using (1e-6)*(1/DACdrive)*(1/coilDriver)*(1/forceCoeff).

For this we used DACDrive = 20/2^16 cts/V, forceCoefficient = 1.694 N/A, and coilDriverTransconductance = 0.011919 A/V. The reason why DACDrive = 20/2^16 cts/V and not 20/2^28 is because we already compensate for the difference between a 16-bit DAC and a 28-bit DAC in the COILOUTF filter bank so we don't need to put that into our calibration.

This gives us:

   Calibration factor [cts/N] = (1e-6)*(1/(20/2^16[cts/V]))*(1/0.011919 [A/V])*(1/1.694 [N/A])

     = 1.623e5 [cts/N]

Then multiplying this calibration factor by our earlier fractional values for P and Y gives us:

   Pitch slider calibration : 4.7e-3 cts[M1]/urad[M3]

   Yaw slider calibration: 20.9e-3 cts [M1]/urad[M3]