Tracker Status Report
February 6, 2004
1. Thermal Vacuum Testing (N. Mazziotta)
a. The test preparation is proceding following the schedule (which is posted on the Tracker web page).
b. Alenia is making the thermocouples and the blanket.
c. Pisa proceeds in the MGSE procurement and assembly: the base plate has been sent to Plyform for the black paint.
d. Bari is finishing the thermistor acquisition system read-out program.
e. All thermistors seem to work properly at room temperature. We are using a lamp to heat thermistors to simulate a change of temperature.
f. The heater quantity, model and location layout have been defined.
g. Bari has also released a preliminary EGSE schematic, cable connections and pin out.
h. All the updated and new documents related to the test have been posted on the usual Bari web page.
2. Tracker IDD (M. Nordby)
a. M. Nordby and M. Menning are traveling to Pisa next week to reach closure on the drawings.
3. SSD Procurement (R. Bellazzini)
a. The order for the last 2000 wafers is on the President’s desk in Italy awaiting signature. Receipt is expected by the end of the month.
4. Ladder Assembly and Test (A. Brez)
a. 834 ladders have been assembled
b. 16 ladders were rejected
5. Bottom Tray Closeouts and Assembly (J. Martin)
a. The second phase at COI, final machining, is still on hold.
b. Martin Nordby and Mike Menning are reviewing and correcting the drawings and will continue with this through the weekend.
c. We hope to have the drawings ready for signature next week, to release COI to start machining.
d. The bottom tray assembly drawing is also being reworked and will be reviewed with the Pisa group next week.
6. Bottom Tray Titanium Parts and Flexures (M. Menning)
a. As of Thursday morning Feb 5, review of the drawings for the corner brackets, corner flexures, and side flexures for the bottom tray are complete and corrections are being incorporated. The first set of check prints will be complete by noon on the 6 th. A copy will be sent to Erik Swensen for review and Martin and Mike will take a set of prints with them to Piza.
7. Bottom Tray Static Test (E. Swensen)
a. Hytec is currently working towards a ship date to SLAC of Monday, February 9, 2004. At the present, there may be a slip of 1-2 days due to scheduling issues at Hytec, but they are working hard to meet the Monday ship date.
b. M. Menning at SLAC has taken an action to design and build a new part for the fixture to hold the bottom tray with the new flexure/Grid interface. Hytec will send him the drawings for the existing parts and assembly.
c. The fixture will go from SLAC to Italy. Initial trials and training with the EM bottom tray will take place immediately following the EM T/V test.
8. Bias Circuit Fabrication (R. Johnson)
a. The complete flight lot of circuits has been delivered. They were built to a redlined version Rev-4 version. The redlines are incorporated in the Rev-5 that is out for release. It looks like as of today all issues are resolved with this drawing and inspection of the bias circuits at SLAC can proceed.
b. SLAC has to add serial numbers to a small fraction of the circuits. The goal is to get them all inspected and shipped out by Feb 23.
c. CMM measurements came in from Italy just today indicating a 0.2 mm error in the positioning of the alignment holes. Work is starting at SLAC to verify this and determine whether it is a drawing error or manufacturing error (so far it looks like the latter).
9. Bottom Tray Panel Assembly Tooling (R. Bagagli)
a. Riccardo finished the 3D drawings and is now completing the 2D drawings with tolerances.
b. Drafts were sent to SLAC for Martin and Mike to review before the meetings in Italy next week.
10. Honeycomb Cores (J. Tice)
a. The shipment of cores is in the customs office in Pisa.
11. Mid Tray Panel Fabrication
a. Plyform is ready to start assembling face sheets to cores.
b. The procedure document is ready to go out for final release.
c. The drawing set for the thin-converter trays is complete and released. Some review of heavy tray drawings is still in progress.
12. Tray Panel Bakeout (F. Belli)
a. For the bakeout system the Roma-II group is now purchasing:
i. 10 new Dallas DS18S20 digital thermistors, in order to monitor temperatures at the center of any tray.
ii. 1 analog precision thermal probe with calibration certificate to be used as reference.
b. They are building a readout board in order to record the pressure values read by vacuum sensor together with temperatures.
c. T. Venator still has an action to review the requirements for this process.
13. PWB Machining and Inspection (D. Rich)
a. 80 short/20 tall TMCM PWBs have been machined and inspected. TMCM height dimension passes for all units. Approx. 10% exceed the parallelism requirement: parallel to bottom edge (datum B) within 0.050 mm. All violations to this requirement fall within 0.050-0.070 mm. An NCR will be generated and dispositioned for these units.
b. 118 more TMCMs that have coupon testing completed will be delivered to Holt machine today.
c. SLAC established panel coupon testing priorities and coordinated with GSFC to conduct coupon testing in a prescribed order. We have prioritized coupon testing based on which panels will yield the highest number of PWBs (max 5, min. 1 PWBs per panel).
14. Pitch Adapter Receiving and Inspection (D. Rich)
a. The Pitch Adaptor Inspection Fixture was designed and fabricated. First article set-up is to be conducted today by T. Nakashima (Richard Gobin LAT QA is supporting this effort).
b. We are looking at the cycle time to conduct screening and determine the rate that can be achieved. Once the Pitch Adaptor yield is determined, we will re-order and attempt to have the supplier compensate for the Pitch Adaptor shrinkage.
15. Nano-Connector Fabrication (J. Tice)
a. Due date for the first shipment of male connectors is planned for Feb. 9, pending results from Omnetics on the bonding process (high priority).
16. ASIC Fabrication, test, and dicing (R. Johnson)
a. Several GTRC-V7 wafers were probe tested. The chips function as intended with >90% yield.
b. One wafer is being diced, so chips will be available for testing on MCMs and for inserting into the Teledyne pre-production Monday or Tuesday.
17. Polyswitches (H. Sadrozinski)
a. Polyswitches are in hand at Teledyne with about 100% spares, tested, and approved by the PCB.
b. UCSC confirmed by direct tests that when an MCM short circuits the polyswitches protect the system and allow all MCMs lower in the stack and on other sides of the tower to continue functioning (this did require adding current limiting resistors on the cables on the GTRC address lines).
18. MCM Test System (R. Johnson)
a. The software is being updated to incorporate additional tests with just a single connector attached, repeated for each side, to verify better the redundancy.
b. The two documents, numbers 249 and 1971, were finalized and submitted for release.
19. MCM Assembly and Test (D. Rich)
a. MCM Preproduction Status:
i. 10 completed and shipped to Italy.
ii. 4 completed and in storage; will go to UCSC next week for pitch-adapter continuity tests
iii. 14 received by SLAC, thermal cycled, and presently in burn-in
iv. 8 completed electrical testing at Teledyne and are in encapsulation
v. 5 are in earlier stages of assembly at Teledyne
vi. 10 tall boards are starting production, using the new GTRC-V7 chip that is available starting this week.
b. The flight-production PRR will be held Feb 10 at Teledyne.
20. MCM Burn-In and Acceptance Test System (R. Johnson)
a. The procedure document is still out for release.
b. 14 preproduction boards are in burn-in at UCSC. The move of the system to the SLAC cleanroom is pending receipt of a new TEM/PS.
21. Tray Assembly Tooling for Integration of Ladders and MCMs at G&A (A. Brez)
a. A draft drawing for tooling for installation of ladders on bottom trays is ready and was sent to SLAC.
b. Machining has started for mockup trays for testing MCM mounting and wire bonding.
22. Tray Thermal Cycle (N. Mazziotta and C. Cecchi)
a. We have tested the two climatic chambers. We have in Terni one of 1 m2 and one of 2 m2; everything is working.
b. The test plan and procedure are still in progress. The test levels and the number of cycles need to be discussed and defined.
c. Next week the Bari group is going to Terni in order to establish the set up of the boxes in the climatic chamber. The Bari and Pisa climatic chambers have been checked and approved and will be delivered by Angelantoni mid February.
d. We have ordered the temperature sensors, enough to test a complete tower, plus 2 calibrated sensors to be used as calibration for the others. The plan is to have a cycle only for the calibration of the sensors before and after the cycle of the trays.
e. We have also ordered some grids to be put inside the climatic chamber in order to have 20 tray at once divided in the two chambers. Thus we will beable to cycle one tower in one go.
23. Sidewall Manufacture (A. Brez)
a. Rodini drafted prepreg specifications for procurement and submitted to COI for review.
b. EM thermal and joint coupons are ready to ship to SLAC for testing.
24. Flex Circuit Fabrication and Test (H. Sadrozinki)
a. Mech systems is working hard on resolving minor interference issues.
b. Had a first meeting between mech systems and elec layout persons. We will introduce additional "slack" in the area of the grid flange to allow for CTE mismatch between the Grid and Tracker. This extends the cable length by about 5 mm.
c. We expect for Friday either a final layout for C0 or at least a good idea how soon we will have them.
d. A scramble is in progress to get a PO in place.
e. We have a new proposal to fab the first 12 C-0 cables as non-flight (for EGSE) asap, and then 28 (+4 blank) complete sets of flight cables, after going though the PRR. Note that unlike the flight cables, the EGSE does not have any strict dimensional requirements.
25. Mini-Tower Testing (H. Tajima)
a. New TKR scripts are tested with mini-tower. Detailed checks are in progress.
b. New TKR scripts are being tested with a new LATTE, which requires several modifications. The modifications are still in progress.