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# 2015-09-01 Survey¶

Present:

Tony Millington (ISIS Survey Team)

Jason Tarrant (MICE Integration Engineer)

Chris Rogers (MICE Physics coordinator)

Meeting to discuss recent survey results and comparison with John Palin survey; January 9th 2015

- Datums of new survey fits with datums of John Palin survey to ~0.5 mm
- (Datums are wall mounted permanent survey points)

- ISIS surveyors have defined a new coordinate system, defined by
- Line through quad centres. This was found by constructing a jig that fits in quad bore, with survey probe mounted; and surveying the jig in each of the quad centres; and finding a line through the centres (good to ~0.5 mm)
- Brass plate under D2
- Uniquely defines x-z plane; defines y axis
- Consistent with ISIS tooling height
- Nearly the same as John Palin survey; correct to ~ cms
- Closer to Colin Croxford survey (2006)

- Jason Tarrant noted that we need resurvey of TOF1 and EMR
- Rogers described the
**survey procedure** - Rogers requested document that would describe a procedure enabling a new surveyor to rebuild the coordinate system a priori (i.e. describing jig method)
- Rogers requests, for new surveys
- Description of how the survey was done
- Description of survey points

- See also
- MICE Note 216 Colin Croxford survey
- MICE Note 424 John Palin survey
- MICE Note 436 John Palin survey
- Original discussion with John Palin :

**Edit to add**:

- Rogers received survey report on 13th January, some long email chain reproduced below but in short...
- z-axis is defined by vector with direction given by gravity, as defined by the Laser tracker inclination sensor, and intersecting the M1 point under the dipoles
- x-axis is defined by vector that intersects the z-axis and the centre of Q9 and is perpendicular to the z-axis; Q9 centre defined by the positioning jig
- y-axis is defined as the perpendicular to these two

- Rogers requested revised survey report to clarify these points.

Long email chain:

On 27/01/15 12:46, Millington, Tony (STFC,RAL,ISIS) wrote: > The vertical axis (z) is to gravity, as defined by the Laser tracker inclination sensor. > > Cheers > > Tony > > > -----Original Message----- > From: Rogers, Chris (STFC,RAL,AST) > Sent: 27 January 2015 12:30 > To: Millington, Tony (STFC,RAL,ISIS) > Subject: Re: MICE Surveys > > I don't understand then, how do you define the vertical axis? > > Chris > > On 27/01/15 12:21, Millington, Tony (STFC,RAL,ISIS) wrote: >> Chris >> >> Yes they are, but the x axis is horizontal and defined using the horizontal (ie x,y) coordinates for M1 and Q9. >> >> Hope that helps. >> >> Tony >> >> >> -----Original Message----- >> From: Rogers, Chris (STFC,RAL,AST) >> Sent: 27 January 2015 12:14 >> To: Millington, Tony (STFC,RAL,ISIS) >> Subject: Re: MICE Surveys >> >> On 27/01/15 11:22, Millington, Tony (STFC,RAL,ISIS) wrote: >>> Hi Chris >>> >>> Don't worry about being pedantic - what seems obvious from a survey point of view isn't always obvious from a different viewpoint, so it certainly doesn't hurt to point out what needs to be clearer! >>> >>> * the x axis "MICE Beamline" is the best fit line through the quadrupole centres; nearly, the X axis is a line from M1 to the measured centre of Q9 quadrupole, this being the longest line we can measure. >> >> Let me be thick for a moment - isn't M1 at floor level; and Q9 centre at beam level? >> >> Cheers, >> Chris >> >>> * the x-z plane is defined by the plane containing the MICE beamline >>> and the "M1" point described above; yes >>> * the z axis is defined by a line in the x-z plane intersecting "M1" >>> and the x axis, perpendicular to the x axis; yes >>> * the y axis is defined by a line intersecting the x axis and z axis >>> and perpendicular to both; yes >>> * your coordinate system is right-handed. Yes >>> >>> Z= 0 is at 603 below ISIS tooling height, floor level varies from >>> approx. -1210 to -1900 (depending on which section of floor) The MICE beam height is 465.65 as a mean of the measured magnet centres, from what I can find in the original documentation and design notes the beam was intended to be at 138mm below tooling height. >>> >>> I think that answers your questions - please let me know if you need anything else. >>> >>> Cheers >>> >>> Tony >>> >>> >>> -----Original Message----- >>> From: Rogers, Chris (STFC,RAL,AST) >>> Sent: 23 January 2015 17:19 >>> To: Millington, Tony (STFC,RAL,ISIS); Tarrant, Jason (STFC,RAL,TECH) >>> Subject: Re: MICE Surveys >>> >>> Hi Tony, >>> Thanks a lot for this, this report looks great! >>> >>> Can I ask for a clarification. You write in MICE Hall Re-Survey: >>> >>> "The Brass scribed plate located beneath Magnet D2 has been surveyed (Point 'M1'), this point represents the origin of the MICE Beamline." >>> >>> My understanding is that: >>> * the x axis "MICE Beamline" is the best fit line through the >>> quadrupole centres; >>> * the x-z plane is defined by the plane containing the MICE beamline >>> and the "M1" point described above; >>> * the z axis is defined by a line in the x-z plane intersecting "M1" >>> and the x axis, perpendicular to the x axis; >>> * the y axis is defined by a line intersecting the x axis and z axis >>> and perpendicular to both; >>> * your coordinate system is right-handed. >>> >>> Apologies for being pedantic, I am a computer programmer so I like these things uniquely defined! Or maybe I misunderstood from our meeting? I spoke to Henry and he indicated that the x-axis (z=0) is at floor level, so perhaps I misunderstood? >>> >>> Cheers, >>> Chris >>> >>> On 13/01/15 12:36, Millington, Tony (STFC,RAL,ISIS) wrote: >>>> Jason/Chris >>>> >>>> I've attached completed survey reports and files for the MICE Hall >>>> resurvey and the Proton Absorber survey. >>>> >>>> Hopefully the format(s) include all the info and data you need - >>>> please give me a shout if there is anything missing or you need clarification. >>>> >>>> Kind regards >>>> >>>> Tony >>>> >>>

Updated by Rogers, Chris almost 9 years ago ยท 15 revisions