IOO (IMC)JuneGyu.Park - 17:05 Wednesday 15 February 2017 (2486)
Print this reportInstallation of tilt sensor on the MCE mirror[Seiji, Kyuman, Keiko, Kirii, JuneGyu]
2/13 Monday
We started installation of FMZI(folded Mach-Zehnder interferometer) tilt sensor.
There are two type for tilt sensor.
One is tilt sensor using He-Ne laser source, another is tilt sensor using laser diode source.
We started installation with He-Ne laser version.
To install tilt sensor, we removed oplev from the pylon.
After finish the installation of tilt sensor, we found that He-Ne laser is not working. (Still we have no idea about the reason)
So we removed He-Ne laser version and installed laser diode version.
We finished installation of tilt sensor around 16:30
instrument list
- Laser diode module for tilt sensor
- Laser diode driver
- Detector module for tilt sensor
- Electronics module for tilt sensor
- Dc Power supply 2EA -> KAGRA.
- Oscilloscope -> KAGRA
2/14 Tuesday
- Installation of tilt sensor and optical lever
We fixed alignment of tilt sensor and measured output signal with Oscilloscope.
After finishing tilt sensor work, We installed optical lever.
To install optical lever and tilt sensor on the same place, we fixed the beam hight of optical lever.
Beam hight of optical lever became 10cm higher than before.
We didn't calibrate optical lever yet. We just checked the alignment of optical lever and output signal.
We found that tilt sensor model in the digital system of KAGRA is not working properly.
It was working only for yaw measurement. We didn't found the reason. We are trying many way.
- Balancing of coil current of MCE mirror actuator
We found some unbalancing issue on MCE mirror actuator.
So we did some calibration work.
We gave the same current to each coil in sequence and measured the tilt.
From the result we found that polarity of magnets are all same except H3.
And the forces induced by current in H3,H4 are weak come pare with H1,H2.
So we adjust the gain of output current in Coil H3,H4. It works well now.