Scraps of text for incorporation in the VIS Meeting Minutes
Type B (Mark)
Past week report
At Kamioka (Mark, Fabian, Enzo, Perry, Hirata-san):
- Filed crane adapter ring to make it fit better on the hook.
- Debugged the BF and SF LVDTs (the signal generator had lost its settings in the rack shutdown).
- Debugged the TM-H4 OSEM problem (a "Type 3 extension cable had gone bad).
- Weighed eyebolts used to lie the SF.
- Shipped the old pico driver and joystick back to Mitaka for Eleonora.
- Borrowed a second pico driver ("PR3") and set it and "BS" up in the rack.
- Practiced driving the BF cap picos with the new drivers.
- (With help from Miyo-kun) got the pico MEDM screens running.
- Replace the temporary "PR3" driver with a new one "BS_BF", and renamed "BS" to "BS_IM".
- Checked all the DIO connections to the LPCD and connected up the HPCDs. With help from Kokeyama-san we can now see all the drivers from EPICS.
- Worked on balancing the BF/IRM/IM... section. Sometime during this work, the IM sank and would not come back to its proper position even with the fishing rod. We put a scale under the RM and found that the imbalance was 488 g. Using the fishing rod we got this down to 235 g, but we found that the direction of the stepper was not consistently related to the direction selected on the driver screen - we had previously noted that "left" was "up, but driving "up" the imbalance would decrease to 235 g and then start increasing again, indicating the stepper had bounced off some obstacle. (There was no obvious sound when this happened, unlike at the low end.)
- We decided to give up on tuning the height of the IM with the fishing rod and to proceed with the test hang by locking the BF keystone at the desired height.
- Hirata-san installed the PI fishing rod and magic wand, and did more work on changing the PI LVDT connectors from female to male.
- Enzo made many edits to the circuit diagram, adding the DIO for the HPCDs and correcting minor mistakes.
Plan for coming weeks
For more detail, see KAGRA/Subgroups/VIS/TypeB/ToDo.
Week of 4/17:
- Install temporary ballast mass in SF.
- Lift SF/BF/... section and check total weight and SF balance.
Continue swap of PI LVDT connectors (female->male)
- Start preparing LBB spring units.
Week of 4/24:
- Crane in PI.
- Connect SF/BF... section.
- Temporarily remove PI and adjust SF ballast if necessary.