25th March 13:00 in R9 lab
To summarise what we discussed today.
Survey coordinates system¶In general:
- +x is along the beamline (towards the main R9 door as currently installed)
- y is across the beamline - positive y is undefined
- +z is up
- y-z plane is defined by the least-mean-squares fit of the end flange holes on the downstream face of the outer "pcd" flange (defines x-axis and x=0)
- z-axis defined by line between the top hole and the bottom hole (defines y=0)
- y-axis is the perpendicular to z-axis in the y-z plane
- z=0 is defined by the mean z of left-most and right-most point on the end flange
- Rogers comment: physics software uses right-handed coordinate system so propose we do also; implies while looking towards positive x, positive y is to the left
- Request that we have access to raw data and as much information as possible about the data format
- Propose transferring data by memory stick to R9 local data store
- Need to find out number of files/file size/data format
- John also has some proprietary software for extracting the position data - and converting by hand to e.g. excel format
Survey equipment¶Survey can be either by:
- "Absolute Distance Measurement" - ADM
- Use IR device and speed of light in air to measure distance
- Interferometry using Helium Neon laser
- wavelength ~0.0158 micron
- Survey is to centre back face of the survey point
- e.g. centre of the hole on the object face for pin mounted survey probes
- John will be at RAL on 9/10 April to take some data for spectrometer solenoid alignment device - would be nice to have a practical demonstration of the survey device!
- Discussion on survey data
- survey uses xit format which appears to be proprietary binary format.
- documentation is in a proprietary (adobe indb) format. Nonetheless we should have access to the files. There was also some discussion on how the MICE hall is/will be surveyed.
- Discussion of survey details