Data aquisition system is fixed, and now we can use the Dataviewer to measure Q-values of the ringdowns for each DOF, each optics.
First of all, I measured MC1 suspention damping servo for a test.
What I did:
1. Used DAQ channels activated in this entry(#3690) to see and compare the ringdowns when the damping servo is on and off with the Dataviewer.
2. Plotted the data and fitted the ringdown using this formula;
I used python's scipy.optimize.leastsq for the fitting.
3. Calculated the resonant frequency f0 and Q-value using following formulas;
4. For plotting, I subtracted the offset(=p).
All parameters I used for this measurement are automatically saved here;
(-1,0,1 for all matrix elements, GAIN=3,3,3,150 for POS,PIT,YAW,SIDE)
Attached is the plot of each 4 DOF ringdown when servo is off and on.
"servo off" means off for that DOF. Servo for the other 3 DOFs are on.
As you can see clearly, the damping servo is working.
The resonant frequencies and Q-values calculated from the fitting are as follows;
Resonant frequencies and Q-values have about 1% and 10% error respectively.
I estimated it from my 2-time measurement of the POS ringdown.
- Find and modify some scripts to optimize the matrix elements
- Calibrate the displacement
- Do the same thing for other optics