<> = Agenda/Minutes = [[https://zoom.us/j/203743987|Zoom Meeting]] ---------- = CRY+VIS Interface Meeting = Date: 2021/6/18 13:00-13:40 Participants: Takahashi, Ikeda, Miyo, Ushiba, Uchiyama, Sato, Yokozawa, Tomaru, Aso、Hirata [[http://gwwiki.icrr.u-tokyo.ac.jp/JGWwiki/KAGRA/Upgrades/PostO3Upgrades|Post O3 Upgrade portal]] == Schedule == * IX: H4 geophone was replaced. Top chamber was closed again. TF measurement of MN is on going. * IY: Schedule: Rough alignment of TM was scheduled on 6/22. * EX: Adjustment of Yaw FR and IP tuning was finished. Broken cable was recovered. Top chamber was closed. . [[https://klog.icrr.u-tokyo.ac.jp/osl/?r=17134|Broken cable]] * EY: Assembly of payload has been almost finished. Jig for mirror cleaning will be delivered on 6/21. Measurement of viewport is on going. == Status == * Corrugate tube fixing jig: Delivery and implement were scheduled on 7/12-13. * TM height setting: Next target is ITMY. * Commissioning in air: X-arm. * Commissioning in vacuum: * Overall commissioning: * Acceptance check: Group work is set every Friday. * PF actuator: After SC. * Jig for FC painting: * Separation of rack in 2F: On the maintenance days in July. * Disassembly of PRM/PR2 assembly frame: This was scheduled on 6/28-29. == Discussion == ---------- = VIS Meeting = 14:00-14:40 Participants: Takahashi, Hirata, Sato, Fabian, Tanaka, Node, Aso, Terrence == Klog == This is generated by python script in /users/Miyo/dropbox/Script/scrapping/main.py. == Summary Report == === Type-A === * Tuned the F0 in IY. * Adjusted the yaw FR in EX. Tuned the IP. The H4 geophone was put on the IP. Repaired some in-vacuum cables. * Closed the top chambers in IX and EX. === Type-B === * ==== Limit switches in SR2 and SR3 ==== There were three switches that didn't seem to be working. Hirata-san fixed them and we checked them with the multimeter. They are working now ==== SRM ==== * We measured IP TF on Monday: * The resonant frequencies in L and T looked low enough (63 and 55 mHz) so we didn't adjust the ballast masses. * The coherence wasn't bad but not excelent either; the frequency resolution was 10 mHz. * Terrence measured TFs again with a better frequency resolution and found that L and T are highly coupled. [Terrence] * Fabian locked the SRM IP so I can measure the LVDT sensor noises. * I measured the geophone readouts as well when the IP is unlocked. The suspension is quiet enough so these can be used as sensor noise estimates. [notebook sneak peek] * I then measured transfer functions and cross-transfer functions. * cross-coupling is confusing. Explain with figure: [[https://klog.icrr.u-tokyo.ac.jp/osl/?r=17137|klog 17137]] * I reverted the sensing matrix and the actuation matrix using Mark's old matrix, which is derived from geometry. * Cross-coupling is still confusing between L and T. But at least I can decouple L2Y, T2Y, Y2L and Y2T. * I suspect the lowest frequency modes are L-T coupled. I am pretty sure L and T sensors are not 100% coupled as suggested in the figures. * I compared the L and T readout with seismic noise in the x-arm and y-arm direction and L has minimal coherence with x-arm while T has minimal coherence with y-arm. * Peaks are too close :*(. * Some opinion about the RT-model * LVDTALIGN and ACCALIGN matrices are great for sensor diagonalization. * Why don't add something like COILALIGN (for actuation)? ==== BS ==== We revisited the BS IP to check stability and values of resonance frequencies. * When we adjusted the ballast mass before the temperature 22.7 degrees, this week was 23.5 degrees; O3GK temperature is 23 degrees. * I moved the IP close to the setpoints using the horizontal fishing rods: it looked unstable, it began moving by small amount but it suddendly moved a lot (e.g. from -1.5 mm to 1.5 mm). With some care I was able to move it at the setpoint and measured TFs, '''the resonant frequencies were 43 and 86 mHz for L and T respectively'''. * '''We removed 4.5 kg''' and and the frequencies changed to '''93 and 70 mHz for L and T respectively. ''' * With the same amount of mass we tested different distributions to check whether we can reduce the assymetry between the resonant frequencies in L and T: * See klog. * '''The assymetry remains around 25 mHz: one is typically around 65 mHz and the other one around 90 mHz.''' * Becuase of temperature changes one might be too low and the other too high. * L and T seem strongly coupled. * I wonder how to proceed: during installation we were not able to distribute the masses evenly around the circumference becuase the magic wand (yet to be conforimed with a klog entry). === Type-Bp === === Type-C === === Electronics === === Control === == Schedule == See [[http://gwwiki.icrr.u-tokyo.ac.jp/JGWwiki/KAGRA/Subgroups/VIS/Schedule|Schedule]] * Type-A team: ACC preparation * Type-B team: Remaining work '''Milestone''' * ''IMC suspensions are ready in air [40]'' will finish 2021/04/21. * ''PRs are ready in air [643]'' will finish 2021/07/09. * ''ETMX is ready in air [656]'' will finish 2021/08/25. * ''ITMX is ready in air [657]'' will finish 2021/08/31. * ''ETMY is ready in air [658]'' will finish 2021/09/16. * ''ITMY is ready in air [659]'' will finish 2021/11/08. * ''BS is ready in air [691]'' will finish 2021/11/24. * ''SRs are ready in air [663]'' will finish 2021/12/20. * ''Output suspensions are ready in air [695]'' will finish 2021/12/21. * ''TMSY is ready in air [708]'' will finish 2021/??/??. * ''TMSX is ready in air [684]'' will finish 2021/??/??. 2021/03/29 updated == Safety == == Discussion == == Travel Plans == The week from 6/21 * Takahashi: 6/21-22 * Hirata: 6/21-22 * Yano: 6/21-25 The week from 6/28 * Takahashi: 6/28-7/2 * Sato: 6/28-7/2 * Hirata: 6/28-7/2 * Yano: 6/28-7/2 == Next meeting == * 2021/6/25(FRI)