For OMC initial alignment with RF, I implemented some guardian states in OMC_LSC and LSC_LOCK, and also I modified some states of the OMC_ASC guardian.
- OMC_LSC: FIND_RESONANCE_FOR_IAL_WITH_RF, LOW_BANDWIDTH_IAL_WITH_RF, OMC_LSC_LOCKED_FOR_IAL_WITH_RF
- OMC_ASC: PREP_ADS_WITHOUT_QPD, ENGAGE_OMC_ADS_WITHOUT_QPD, OMC_ADS_ENGAGED_WITHOUT_QPD
- LSC_LOCK: LOCKING_OMC_FOR_IAL_WITH_RF, RECORD_GOOD_VALUES_OMC
If you want to the initial alignment to OMC after PRFPMI is locked with 10W, you can do it with the following procedure.
- Request LSC_LOCK to go to "LOCKING_OMC_FOR_PRFPMI" at once.
- Request LSC_LOCK to go to "LOCKING_OMC_FOR_IAL_WITH_RF" while LSC_LOCK stays LOCKING_OMC_FOR_PRFPMI. Then, OMC_LSC try to lock OMC with RF and OMC_ASC goes to "DOWN".
- After locking OMC with TEM00 light, check the trans. power (K1:OMC-TRANS_DC_SUM_OUT_DQ). If the power seems to be lower than 12 mW when PRFPMI input power is ~10W and the RMS fluctuation seems to be somehow small (less than ~2mW, empircally), OMC is locked with RF sideband. go to next step. On the other hand, if the power surpasses 12 mW or the fluctuaition seems to be large (> 5 mW, emprically), OMC is locked with carrier light. In that case, request OMC_LSC to go to "DOWN" at once and request OMC_LSC to go to "OMC_LSC_LOCKED_FOR_IAL_WITH_RF" again manually.
- Request OMC_ASC to "OMC_ADS_ENGAGED_WITHOUT_QPD". check whether ADS maximizes the trans. power (K1:OMC-TRANS_DC_SUM_OUT_DQ) and the feedback signals (K1:OMC-ASC_DOF{1,2}_{PIT,YAW}_OUT16) settle down.
- After the trans.power is maximized and the feedback signals settling down, request LSC_LOCK to go to "RECORD_GOOD_VALUES_OMC". In the state, OMMT2 and OSTM alignments are recorded and offloaded. After that, the OMC lock falls down automatically.
After that, you can request LSC_LOCK to go to the upper states with good alignment to OMC.