Drive Beam quadrupoles f or t he CLIC project : a novel met hod of f iducial isat ion and a new micromet ric adjust ment syst em Hélène MAINAUD DURAND, on behalf on CLIC pre-alignment team

Agenda

• Int roduct ion • A new method of f iducialisat ion:

• Int roduct ion: determinat ion of the magnet ic axis & f iducialisat ion • New proposal • Results

• A 5 DOF micromet ric adjustment system: • Requirements • Descript ion of the solut ion • Process of validat ion and associated results

Out line

A novel method of fiducialisat ion & a new micrometric adjustment system

Int roduct ion CLIC project

Int roduct ion CLIC module

• Length of 1 module = 2 m • 20 000 modules in total • 2 DB quads per module • 40 000 DB quads in total!

Some dat a:

DB quad pre -alignment

• For a sliding window of 200 m • Std deviat ions of magne t ic axis of DB

quad w.r.t a st raight line fit < 20 µm

Int roduct ion

Fiducialisat ion of components

Fiducialisat ion of their common support

Alignment of components on support

Whole assembly ready to be installed

CLIC module

new

new

Novel method of f iducialisat ion

Fiducialisat ion: → precision within a few µm

→ accuracy est imated at 40 µm

St andard process

Wire cente red and aligned to find t he posit ion minimizing the oscillat ion amplit ude

Wire driven t hrough two ceramic balls in such a way that it is always re inst alled at t he same posit ion

Use of oscillat ing st re t ched wire for MB quad

Novel method of f iducialisat ion

• Determinat ion of the posit ion of wire using cWPS

• Determinat ion of the posit ion of cWPS w.r.t f iducials using a bench • The posit ion of the f iducials of the bench w.r.t . kinemat ic mount of

cWPS has been measured within 0.3 µm + 1 ppm (Leitz Inf inity CMM)

• AT 401 perform precise and accurate measurements of the DB quad f iducials w.r.t . bench f iducials

Components of novel method

Novel method of f iducialisat ion The whole setup

Novel method of f iducialisat ion Process of measurements

DBQ DANFYSIK

Ma rb le

Novel method of f iducialisat ion

Measurements performed on 3 types of wires (Ø 0.1 mm): • Cu-Be (2003) 5 sets • Cu-Be (2013) 4 sets • Cu-Ni 4 sets

Repeat abilit y of t he method

Int e r-comparison be tween methods

• Ent rance & exit of magne t ic axis de t e rmined by both methods

• In t he st andard method, LTD 500 replaced by AT401 measurement s

• Syst emat ism of 27 µm in horizontal • Due to an e rror in CMM

measurement s ? • Incoherencies obse rved by

AT401 performed on 0.5 ‘’ & 1.5’’ t arge t s

Std dev. of coords Y (µm) Z (µm) Ent rance of magnet ic axis 4 4 Exit of magnet ic axis 4 5

Offse t s be tween methods Y (µm) Z (µm) Ent rance of magnet ic axis 26 3 Exit of magnet ic axis 27 1

Novel method of f iducialisat ion

• Same measurements than before

• Same process of calculat ions • But use of LTD 500 instead of

AT 401

Int e r-comparison (LTD 500)

Posit ion of magne t ic axis vs current

• Impact of t he current in t he posit ion of t he magne t ic axis not negligeable ,

• Repeatable

Offse t s be tween coords Y (µm) Z (µm) Ent rance of magnet ic axis 2 7 Exit of magnet ic axis 2 7

The syst emat ism comes from the AT 401 measurement s when performed on two diffe rent t ypes of t arge t s 0.5 ‘’ and 1.5 ‘’

Novel method of adjustment

Requirements: • Adjustment according to 5 DOF (Y, Z

t ranslat ions & 3 rotat ions) • St roke:

• ™ 1 mm in Y and Z (X blocked) • ™ 4 mrad in all rotat ions

• Resolut ion < 5 µm • Must f it the available space • User access only on one side • Load 170 kg

Int roduct ion

Z

Y X

Novel method of adjustment Solut ion proposed

Novel method of adjustment Solut ion proposed

Novel method of adjustment

Validat ion of horizontal & vert ical stand-alone units

Validat ion of the prototype

Validat ion of 2 f inal series

St rategy of validat ion

Novel method of adjustment

• Long term stabilit y ok • No drif t or creeping observed • Resolut ion of t ranslat ions < 4 µm • Resolut ion of rotat ions < 40 µrad • Manual adjustment inferior to 10 ‘ • Second order impact on the vert ical axis while

adjust ing the radial axis and vice versa

Result s of prototypes

2 se ries inst alled successfully in CLEX

Summary

• Combining AT401, CMM, cWPS measurements • A budget of error below 5 µm for the f iducialisat ion

process can be considered • A systemat ism has appeared during the measurements

and seems coming f rom AT401 coupled with 0.5’’ or 1.5’’. To be studied

• The syst em has been successfully inst alled in CLEX, allowing adjustment of t he DBQ according to 5DOF, in le ss t han 10 ‘.

• Resolut ions achieved: • Translat ions be low 4 µm • Rotat ions be low 40 µrad

New method of fiducialisat ion proposed

Novel 5DOF micromet ric adjustment syst em

Perspect ives

• 2 DB quads installed on the same girder, via the 5 DOF micromet ric adjustment system

• Whole assembly installed on a magnet ic calibrat ion facilit y, on a special bench, equipped with addit ional targets and cWPS interfaces (determined by CMM measurements)

• A wire is st retched to perform the magnet ic measurements • It is not the wire that will be displaced to look for the magnet ic axis of

the quadrupole, but the quadrupole it self , using the 5 DOF adjustment system

• Once in posit ion, the posit ion of the wire is measured, using a combinat ion of cWPS, AT401, CMM measurements, in the girder referent ial f rame.

Combinat ion of both methods during t he fiducialisat ion process of DB quads

This is an ext rapolat ion of t he PACMAN project…