As we decided to try the dithering technique to keep long term alignment of the cavity, in the past day I realized the software necessary for the job. Both simulink model and MEDM interface. I tried to reuse code from KAGRA as much as possible.

We have how the possibility to send 4 lines for pitch and 4 lines for yaw to each of the 4 suspended mirror. and we can demodulate a cavity signal (to be chosen between GREEN TRA, IR TRA and FC CORR) at the frequency of these lines. Then we can decide to which mirrors to send the correction after properly filtering it.

In order to implement the dithering we should switch from DC local controls for mirrors to AC local control. I quickly realized a preliminary, non optimized version of these AC loops (except PR), which I hope to improve soon. Pic 3.