Minutes of the Tracker Meeting
February 13, 2003
Action Items:
Action items from last week were
reviewed. All were addressed, except
that Tom is still waiting for the composites specification example from Nick.
BJ said that a local Silicon-Valley vendor
can make bias circuit with covers, as requested by Sandro.
Thick tungsten order: Althouse signed the
purchase requisition. It is a $100,000
order. The foils are $10 more than
before, because the vendor said they lost money the last time. There was a bit of an issue with Althouse as
to how was this traded with Sandro, as the foils had been an Italian
commitment. Robert asked if we should
lower the tolerance further to get the price down. Gary is rechecking the thickness specification
Luca Latronico said that he will update the
web page at Pisa on the MCM testing.
They raised VDD and then the register readout worked on the module that
they had problems with last week. Six
MCMs were mounted onto mini-tower trays and retested with no change found. They are now at G&A for tray
assembly.
G&A has assembled 4 trays with ladders
and MCMs. One will return tomorrow
already wire bonded and ready for testing.
Sandro had problem with the pitch adapter on one MCM. The glue was not holding, so he will try to
repair it at Pisa. Tom apologized that
this was a known problem that he forgot to fix before shipping them to
Pisa. Alignment of the ladders in xy is
good. The maximum displacement is 12
microns.
G&A had problems with the non-conducting
Nusil glue for ladder attachment.
Initially they had a 400 micron vertical displacement instead of 150
microns. The reduced the glue volume
and went down to 300 microns. Then they
reduced more and will test again.
Riccardo is in Rome testing the holographic
system. They tested several trays and
found the same results as in the shake test.
Erik reported that the modeling is done on
the bottom tray. There are a couple of
hot spots still at the sidewall attachment, but he is waiting for new
allowables for the sidewall attachments.
The allowables in the model do not reflect the new insert design, so he
believes that it will be okay without change. Hytec is testing sidewalls of
YS90 to get the needed allowables.
Tom said that he has another set of coupon
drawings from COI that he is struggling to open. He will send the info to Erik.
Erik reported an issue with the corner
flexure: in the titanium blade there is a margin of only 10% at 45g random-vibe
accelerations, instead of the desired 12%.
On the other hand, new numbers from Martin on the interface loads look
good and are no problem. They are
equivalent to only about 22g. The tower
lateral resonance frequency is now up to around 160Hz.
Tom said that he would like BJ to start
working on updating the bottom tray drawings. He needs to get something to COI to start bidding for the closeout
material layup.
March 14 is the date to get the reduced model
to Martin for coupled loads analysis.
Erik will try to get it there earlier, even.
Erik said to BJ that the core thickness of
the bottom tray is unchanged.
Tom will talk to BJ about mass estimates for
Martin.
Tom noted that there is a telecon tomorrow on
connectors. The MCM PWB layout update
is pending a final choice of the connector.
Since Sandro was not able to be present, Tom
and Robert will call him tomorrow to try to finish the agenda.
Tracker Peer Review Agenda
(draft)
|
Section |
Title |
Presenter |
Time allocation |
|
1 |
Introduction, Overview, & Status |
R. Johnson |
|
|
|
Schedule Summary & Critical Paths, Risk |
T. Borden |
|
|
|
Performance predictions vs requirements |
W. Atwood |
|
|
2 |
Electronics Design and Status |
R. Johnson |
|
|
|
Mechanical Design and Status |
T. Borden |
|
|
3 |
Engineering Model Tower Status |
|
|
|
|
EM Mini-Tower Status and Results |
|
|
|
4 |
Safety and Mission Assurance |
Johnson/Virmani |
|
|
5 |
Parts and materials procurement overview |
N. Virmani |
|
|
|
Electronics parts and materials |
N. Virmani |
|
|
|
Mechanical parts and materials |
|
|
|
6 |
Fabrication Overview |
|
|
|
|
SSD production, receiving, inspection |
|
|
|
|
Ladder fabrication |
|
|
|
|
Tray panel fabrication |
|
|
|
|
MCM fabrication |
|
|
|
|
Tray assembly |
|
|
|
|
Tower module assembly |
|
|
|
|
Product shipping and storage |
|
|
|
7 |
Test Plan Overview |
|
|
|
|
EGSE and MGSE |
|
|
|
|
Electronics Module Testing |
|
|
|
|
Panel and Tray Testing |
Mazziotta? |
|
|
|
Tower Testing |
Mazziotta? |
|
|
|
I&T Support |
|
|
|
|
On-orbit calibration and test |
|
|