j.-c. barri è re
DESCRIPTION
A TLAS Align. PDR J.C. Barri è re (Saclay). P RAXIAL A LIGNMENT S YSTEM (barrel). positioning. Tool for the platform positioning. Platform positioning during MDT construction. QA/QC: in production site and at the CERN X-ray tomograph. J.-C. Barri è re. calibration. calibration of - PowerPoint PPT PresentationTRANSCRIPT
J.-C
. Bar
rièr
ePRAXIAL ALIGNMENT SYSTEM (barrel)
posi
tion
ing
cali
brat
ion
calibration of PRAXIAL part
ATLAS Align. PDRJ.C. Barrière (Saclay)
calibration of AXIAL part
PRAXIAL activeoptical elements
Platform positioning duringMDT construction
Tool for the platformpositioning
QA/QC: in production site and at the CERN X-ray tomograph
conclusion
Top view
PRAXIAL ALIGNMENT SYSTEM Principle
The PRAXIAL system is used to unite a layer of chambers (about 6 MDT) to form a single “rigid” layer. It is composed by two systems:
the axial system (overlapping Rasniks // to beam axis – z –),the proximity system (2 short crossed Rasniks).
The requirements for the axial are: ±5 m, for the proximity system: ±5 m and ±30 rad.
The precision on the positioning of both systems are: ± 25 m
3D view
Top viewaxial Rasnik
axial Rasnik
2 proximity Rasniks
MDT chambers
Reference system
Toroid rib
ATLAS Align. PDRJ.C. Barriere (Saclay)
X
Z
Atlas axis
MDT- n MDT- n+1
installation of PRAXIAL platforms(on each production site)
calibration of the PRAXIAL
positioning tools
J.-C
h. B
arri
ère
PRAXIAL ALIGNMENT SYSTEM (barrel)po
siti
onin
gca
libr
atio
n
Calibration of PRAXIAL part
final QA/QC with the CERN X-ray tomograph
ATLAS Align. PDRJ.C. Barrière (Saclay)
calibration of AXIAL part
Principle
PRAXIAL ALIGNMENT SYSTEM Caliprax
ATLAS Align. PDRJ.C. Barrière (Saclay)
HARDWARE:•6 axis motorised table with end-switches,
range ± 5 mm, ± 10 mrad.•stiff mechanical structure,•displacement sensors (rasnik/linear encoders)
= 1µm,•temperature probes,•1 PC computer for control and calibration.
SOFTWARE:•ICARAS (rasnik readout),•MINUIT routines (fit),•C++ (general program).
ACCURACY•± 5 µm,•± 30 µrad.
PRAXIAL ALIGNMENT SYSTEM Calibration of proximity part.
ATLAS Align. PDRJ.C. Barrière (Saclay)
A u tom atic ca lib ra tionO p tion 1
G eom etrica l recon s tru c tion :3 0 /3 6 p aram eters
A u tom atic ca lib ra tionO p tion 2
lin ear ap p roxim ationTran s fe rt m atrix: 4 8 p aram eters
Z erop raxM ech an ica l b en ch (m arb le tab le ) a t
th e n om in a l p os it ion
2
2
2
2
1
1
1
1
matrix tansfert : T
Yccd
Xccd
Yccd
Xccd
Z
Y
X
dZ
dY
dX
Z
Y
X
Z
Y
X
Z
Y
X
Masks & CCD:
Lenses:
2
2
2
2
1
1
1
1
Yccd
Xccd
Yccd
Xccd
1 movement: 2*4 known parameters
1 movement: 6 know parameters
Zd
Yd
Xd
dZ
dY
dX
8N > 36N: number of measurements
Known withlinear encoders Measured with
praxial rasniks
At least 66 movements
PRAXIAL ALIGNMENT SYSTEM Manual calibration.
ATLAS Align. PDRJ.C. Barrière (Saclay)
1st step: 40 movements for calibration.
2 nd step: 140 movements:55 pure movements95 combined movements.
installation of PRAXIAL platforms(on each production site)
calibration of the PRAXIAL
positioning tools
J.-C
h. B
arri
ère
PRAXIAL ALIGNMENT SYSTEM (barrel)po
siti
onin
gca
libr
atio
n
Calibration of PRAXIAL part
final QA/QC with the CERN X-ray tomograph
ATLAS Align. PDRJ.C. Barrière (Saclay)
Calibration of AXIAL part
Principle
ATLAS Align. PDRJ.C. Barrière (Saclay) PRAXIAL ALIGNMENT SYSTEM
Calibration of axial part.
1st STEP (manual operation):
Calibration of 3 cubes containing Rasnik elements (mask, Lens, CCD)
7 measurements (X, Y, & ) to control the position of the rasnik elements in the cubes and the bench geometry.
2nd STEP:
Calibration of the axial elements.One of the cubes is replaced by the axial element to be calibrated.
1 measurement/ axial optical element5 m long marble
2x
ATLAS Align. PDRJ.C. Barrière (Saclay) PRAXIAL ALIGNMENT SYSTEM
Conclusion: status & schedule.
PROXIMITY CALIBRATION (2*1250 units, 6 different gaps):
Status: 6 axis motorised tables, endswitches, linear sensors are available. Software is under construction. Mechanical structure is studiedSchedule: first calibration in september 2001.
AXIAL CALIBRATION:
Status: principle of the calibraton has already been tested.Sofware exists and has to be adapted. Schedule: first calibration at end of 2001.
POSITIONNING & CONTROL TOOLS:
The tools are now understood (4*6 positioning tools delivered + control towers). Many error sources are possible.Differential sag between tubes and wires has to be checked.Next X-tomo control end of april 2001 (4 masks delivered).
Chambers A or C Sectors17,5 18,1 18,3 18,6 18,8 18,9 19 19,8 32,2 32,8 32,9 33 50,5 198,8 343,3 388,3 452* 489* 1266,4* 1302,4*
BIS Standard (x16) 1 5BIL Standard (x10) 3 1 1BIL S13 (x2) 2 2 1BIM S11 or 15 (x4) 4 1BIR S11 or 15 (x4) 1 1 1 1 1 1
BMS Standard (x12) 1 1 1 1 1BML Standard (x16) 3 2BMF S12 or 14 (x4) 1 1BOS Standard (x12) 5BOL Standard (x12) 4 1BOF S12 or 14 (x4) 5 3
Total (all sectors) 108 72 12 32 66 12 98 10 24 4 4 4 12 2 12 12 4 4 4 4
Distances between chambers (mm)
Chambers A or C Sectors17,5 18,1 18,3 18,6 18,8 18,9 19 19,8 32,2 32,8 32,9 33 50,5 198,8 343,3 388,3 452* 489* 1266,4* 1302,4*
BIS Standard (x16) 1 5BIL Standard (x10) 3 1 1BIL S13 (x2) 2 2 1BIM S11 or 15 (x4) 4 1BIR S11 or 15 (x4) 1 1 1 1 1 1
BMS Standard (x12) 1 1 1 1 1BML Standard (x16) 3 2BMF S12 or 14 (x4) 1 1BOS Standard (x12) 5BOL Standard (x12) 4 1BOF S12 or 14 (x4) 5 3
Total (all sectors) 108 72 12 32 66 12 98 10 24 4 4 4 12 2 12 12 4 4 4 4
Distances between chambers (mm)