1. Rod adaptors for module tests Module positioning studies
2S Module meeting, Tracker week, 16 July 2012 Rod adaptors and studies on module positioning Refers to work by Tristan Falcy, Luc Kottelat, Aleksis Chávez Niemelä and Riikka Häsä
Rod adaptors for module tests
Module positioning studies
On-going + Next tasks
Summary
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

2. Rod adaptors for module tests
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

3. TOB Rod with 2S modules
2S module
Adaptor
Existing TOB rods (tens available) can be used for first module tests
E.g. cooling tests
But, new module dimensions do not directly match the rod
Need adaptors
TOB Rod frame
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

4. TOB Rod with 2S modules
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

5. Adaptor design 3 connection bars in carbon-fibre composite
Support and alignment of the 2S module
Support and alignment on the rod
4 support/cooling contacts in aluminium
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

6. Adaptor production 2 adaptors have been produced
Completed adaptor
3 connection bars in carbon-fibre composite
4 support/cooling contacts in aluminium
2 adaptors have been produced
More adaptors can now easily be made, if/when needed.
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

7. Rod + Adaptor + 2S module mock-up
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

8. Module positioning studies
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

9. Barrel rod with 2S modules
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

10. Studies on module positioning
Study on combining module positioning inserts and captive screws (for improved module handling)
Module placed on supports
Module
Positioning
Screws tightened
Support structure
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

11. Study on module positioning
Aluminium dummy module placed on a support plate
Small brass positioning inserts and captive screws
Optical measurement of module positioning
Positioning inserts + captive attachment screws and nearby optical targets
“Module” in aluminium
Support plate in aluminium
Attachment screws
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

12. H7 tolerance on Ø2.5 and Ø3 holes: 0 - +10 μm
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

13. Study on module positioning
Module positioning insert (brass) and captive M1.6 screw with a spring
h8 tolerance on Ø2.5 and Ø3 axis: -14 – 0 μm
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

14. Precision (repeatability) of the positioning
σ = 10 μm
Dummy module installed and removed 8 times, with its position measured after each installation.
Optical measurement accuracy: +/- 2µm
Mean value of results normalized to zero
σ = 17 μm
σ = 11 μm
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

15. Conclusions from these positioning studies
Precision of ~ μm (1 sigma) in module positioning can be rather easily obtained with such small 2 mm high positioning inserts.
If necessary, the precision can be increased by tighter manufacturing tolerances on the components
Precise ‘slot’ hole is more difficult to produce than a precise round hole.
Note: For sufficient cooling contact the module attachment screws must be well tightened. Therefore, the long-term stability is better than the initial precision of such module positioning system.
Captive screws work nicely, but they are space-consuming, need a ‘high’ support insert
Problems with available space and added mass on the final rod assembly
Simple screws are now considered
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

16. On-going + next tasks 2S module meeting, 16 July 2012, indico: 197203
Antti Onnela, CERN

17. Module support design Used as base-line: Rod with modules upside up.
Space for module supports, positioning and screws?
Combine support of two modules?
Modules upside up
+ Radial distance between adjacent sensors is minimized
+ Connectors are well exposed
Total thickness is potentially rather big (here 24 mm). Thickness depends directly on the biggest components
Tight space for module supports and thermal contacts
Modules upside down
+ Total thickness minimized (here 15 mm), allowing compact barrel layers
+ Components are not exposed (= better protected) in the final assembly
+ Good space for module supports and thermal contacts
Radial distance between adjacent sensors is big.
Difficult access to connectors on the module
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

18. Thermal design of the module supports
According to preliminary calculations ΔT of ~5 ˚C expected in the module
Allowing total of 10 ˚C ΔT from silicon to coolant leaves ΔT max 5 ˚C for the module support – cooling pipe – fluid (CO2)
Analysis and preliminary optimisation on module supports on-going
Optimisation between mass and thermal performance of the module support insert
ΔT: 5-7 ºC
ΔT: ~5 ºC
Module analysis (Andreas Mussgiller)
Support insert analysis (Riikka Häsä)
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

19. Module and rod overlaps
Module supports and Cooling contacts at the rod overlap area?
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

20. Module holders
Module holders to allow safe access to module front and back sides.
During module assembly work
During bonding
During testing
During transports
Can one single holder do all, or are different holders for different steps necessary?
Images of preliminary concept studies
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

21. Summary
Adaptors for mounting 2S modules on TOB rods have been designed and 2 first adaptors made.
When planning for module thermal tests see if the adaptor + TOB rod could be a solution.
More adaptors, possibly with different geometries, can be produced.
Module positioning studies done with very dummy modules.
Reasonable positioning precision achieved with small positioning inserts.
Precision can be improved if needed.
Work on-going with module supports.
Need to make them small, for mass and also for limited space available.
Thermal performance needs to be sufficient.
Particular challenges in the rod-to-rod overlap area
First concepts of module holders for assembly, tests, transports
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

22. Thank you for your attention.
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

23. Spare slides 2S module meeting, 16 July 2012, indico: 197203
Antti Onnela, CERN

24. 2S module, Jan 2012 version 3D models by A. Conde Garcia / CERN
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

25. Module positioning: TIB
Inputs from A. Basti / INFN Pisa
Precision insert
Slot insert
Inserts with clearance
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

26. Module positioning: TEC
Inputs from M. Wlochal / Aachen
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

27. Module positioning: TOB
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

28. Module support and positioning: TOB
Support structure
(Rod)
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

29. Module support and positioning: TIB
Support structure
(Cylinder)
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

30. Module support and positioning: TEC
Support structure
(Petal)
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

31. And the net result with TK precision?
Already after first cosmic runs the total residuals with Track Based Alignment are at ~50um rms, and improve within 2008 to ~30um.
Much better than what the mechanics can (reasonably) do!
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

32. Choice of module positioning concept?
All used module positions solutions in the present Tracker have shown to be sufficiently precise, especially after track-based software alignment.
TIB / TEC module positioning is more compact and lighter than the TOB solution.
Use the TIB / TEC solution as basis in the 2S module
Try to also include captive screws, which do not need to be handled individually during module testing and assembly phases.
2S module meeting, 16 July 2012, indico:
Antti Onnela, CERN

33. 2S module meeting, 16 July 2012, indico: 197203
Antti Onnela, CERN