TIPS - October 18 2007 Updates on ACS-R Marco Sirianni October 18, 2007

TIPS - October 18 2007

Updates on ACS-R

Marco SirianniOctober 18, 2007


Agenda

• ACS Status

• ACS-R– Concept– Schedule– EVA activities– Role of STScI


Status of ACSo ACS Side 1 Failed on June 19, 2006

• The ARB identified a most probable candidate for the failure, an Interpoint DC-DC Converter on LVPS 3 board in MEB1

• Precluded all WFC and HRC CCD imaging.• Operations started on side-2 electronics on Jul 4 2006.

o ACS Side 2 failed on January 27, 2007 • Short likely in the Hold Bus • Side-2 is completely inoperable• Side-2 is inaccessible to astronauts for repair• Side 2 is not part of repair mission

o ACS was configured for Side-1 SBC operations only on February 15, 2007


ACS-R• Immediately after the failure of Jan 2007 the HST project

assembled a team for the repair of ACS.

• At the end of February a specific option was select for further study.

• On October 3 & 4 the ACS-R project passed the critical design review.


ACS-R CDRName Affiliation Primary Disciplines

Dennis Dillman NASA/NESC Review Team Chair

Tom Akers Consultant EVA

John Grunsfeld JSC Crew Office STS-125 Crew

Richard Harms HST SM4 SRB Instrument Systems

Denny Holt Consultant Shuttle Mission Mgmt

Chris Iannello KSC Engineering Power Systems

Wes Ousley GSFC AETD Thermal Engineering

Joe Pellicciotti GSFC AETD Mechanical Systems

Pete Salerno GSFC SRO Electrical Systems

Steve Scott GSFC Chief Engineer Systems, C&DH, SW

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.




ACS-R TeamACS Repair Mgr

Peter Alea(ATK)

Mission Assurance

Carl Powell(HTSI )

System Safety

Willian Hill(SRS)

Contamination

Radford Perry(SGT)

ACS Repair PIEd Cheng

(Conceptual Analytics )

Sy s t e msKe vin Bo yce ( G SFC )Be cky Em e r le ( Ba ll )

M e c ha nic a l D e v M grM a r k Tu r czyn

( G SFC )

The rma lJe ff L a sco

( Ba ll)

Flight Sof t w a reBa r b a r a Sco tt

( G SFC )

D C LAu g u styn W a czyn ski

( G ST)

I& TEd Sh a d e

( L M TO )

Ele c t ric a l Le a dIke O r lo w ski

( J& T)

C C D Emula t orM a tt O w e n s

( M EI )

EG SEM a r k Be lz

( J &T )

G SE Sof t w a reKa th le e n M il

( J &T )

Yitin g W e n( M EI )M e c ha nic a l

Greg Waligroski (Ball )Drew Brown (Ball )

St ruc t ura l A na ly s isM ike Be d a ( Ba ll )

Jo h n L e a h e y ( Ba ll)

ToolsTo r ch ia Ke lly

(ATK )

EVAEd R e za c( L M TO )

STSc iM a r co Sir ia n n i

Ala n W e lty

C a rrie rsM in a l Ka sh ka r i

( L M TO )

LVPSL a r r y Tr u b e ll

( Ba ll)

Pa rt s Engine e ringN o m a n Sid d iq i

( G SFC )

C loc k B oa rdsKe n Alb in

( Ba ll )

SID EC A R A SICM a r ku s L o o seR a p h a e l R ica r

FPG AEd C h e u n g

( J& T)

C EB- R Te a m

O pe ra t ions / FSWSteve Arsianian (HTSI )Randy Stevens (LMTO)

SI FSWBe v Se r r a n o( R a yth e o n )

SID EC A R A s y C odeR a p h a e l R ica n d o

M a r ku s L o o se( Te le d yn e )

SID EC A R V &VR o b L a m p e r e u r ( Ba ll)

C h r is D o r a to ( Ba ll )


LVPS H

MEB

Side 1

APB

LVPS O

LVPS H

MEB

Side 2

APB

LVPS O

HOLD Bus

OPERATE BusFailed Element

Suspect Element

PDU 20 Amp Fuse

OPERATE Bus

HOLD Bus

PDU 20 Amp Fuse

Side 1 is fully operational except for the LVPS power to the CEBs.

Currently running on Side 1.

Side 1 is fully operational except for the LVPS power to the CEBs.

Currently running on Side 1. Side 2 is inoperable. Side 2 is inoperable.

+15, -15, +35

+5

+15, -15, +35

+5

WFC CEB

WFC CCD

HRC CEB

HRC CCD

ACS Current state simplified Electrical Block Diagram


ACS-R concept

Restore WFC functionality under side-1 (LVPS failed on 6/2006) by replacing the WFC CEB cards with a new module (CEB-R) powered by a new LVPS (LVPS-R)

Restore HRC functionality by backpowering the existing HRC CEB (the success depends on the status of the existing wire harness within ACS)

Requirement: do not harm SBC


ACS-R simplified Electrical Block Diagram

LVPS H

MEB

Side 1

APB

LVPS O

LVPS H

MEB

Side 2

APB

LVPS O

HOLD Bus

OPERATE BusFailed Element

Suspect Element

PDU 20 Amp Fuse

OPERATE Bus

HOLD Bus

PDU 20 Amp Fuse

Side 1 used to operate the entire instrument except for the CEBs which are

replaced/powered by a new box.Side 2 is inoperable.

+15, -15, +35

+5

+15, -15, +35

+5

New CEB

WFC CCD

HRC CEB

HRC CCD

New Element

New Power Supply


ACS-R Design Concept

PIE = Power Intercept ElementCEB-R = CCD Electronic Box - RepairLVPS-R= Low Voltage Power Supply - RepairPOE = Power Output Element

PIE = Power Intercept ElementCEB-R = CCD Electronic Box - RepairLVPS-R= Low Voltage Power Supply - RepairPOE = Power Output Element

PIEPIE

LVPS-RLVPS-R POEPOE

CEB-RCEB-R


CEB

Astronaut Handrail

Electrical Interface Conector


CEB-R

Replace the original 4 boards with a new element which contains 4 replacement boards

Backplane

Timing Board

Clock B/Y Board

Clock A/X Board

ASPC/Bias Board

Motherboard Mating Connectors


LVPS-R

LVPS-R

ACS HandrailHandrail Post

Post Attachment Clamp

Tether Ring

Grounding Plug

PIE Connector Cover with Tether Ring

POE

Cable Stowing


HRC Backpowering• The ACS-R design provides the option of

backpowering the existing HRC CEB through the existing harness within the instrument.

• One of the main issue is the supply of the +35V. If it can be provided by the original LVPS than it will be sincronized (-> lower noise), but it must be provided by the LVPS-R HRC could be noisier.

• Preliminary tests with flight spare HRC CEB and CCD show no difference


ACS-R TestingBesides the single component testing the full ACS-R system will be

tested with:

• Flight spare HRC CEB (backpowering testing)• Flight spare build for HRC and WFC

– Cannot be cooled as on-orbit– Used for testing with hi-I preamp and detector– Functional testing when lowest noise is not needed

• WFC SITE spare CCDs (+custom cryostat)– Can be cooled to -80 C, crosstalk testing

• CCD emulator– allows readout of a complete 4Kx4K image– adjustable noise level:

• Match on-orbit detector level to determine expected performance• Set noise level very low to verify noise contribution of CEB-R• Set noise level high to optimize timing pattern and CDS for best results.


Schedule Highlights

• Testing with the first engineering module of CEB-R and ACS flight

spare CCDs will start on Oct 25th.

• Flight LVPS ready Mid Jan

• Flight CEB-R ready early March

• Servicing Mission Ground Testing (SMGT) End of February (possibly

a second campaign with complete flight-hardware)

• TV testing - April

• Shipment to KSC - Jun 9

• Launch - August 8


Current Timeline




EVA Tasks• All ACS Repair EVA tasks have been evaluated by suited SM4 crew

•ACS Prep 00:05•Install Guide Studs 00:20•Remove the EMI Grid 00:10

Install grid cutter, actuate, remove grid cutter w/grid•Remove WFC Access Cover Plate and CEB Top Plate 00:45

Install FCP, release fasteners, remove FCP•Remove 4 WFC CEB electronic boards 01:00•Install WFC CEB Replacement Module 00:10•Install Power Supply Module to ACS handrail, mate PIE connector to LVPS-R and POE connector to CEB-R 00:10•ACS worksite clean-up 00:20

Total (w/o door operations) 03:00

•The EVA timeline will continue to be refined through upcoming scheduled NBLcrew training and test runs as well as 1-G activities to address open issues on tool stowage, tool design, fastener access, etc.


EVA Tools

Screen Grid Cutter

Fastener Capture Plate

Card Extraction Tool


The role of STScI

• Support ground calibration to identify areas where science operations may need modification (commanding, proposal preparation, data processing)

• Support IPT in the definition of the ACS-R AT/FT• Support the scientific evaluation of the FT• SMOV planning and on-orbit re-commissioning


ACS-R in SMOV• ACS-06 CCD Functional Test\• ACS-08 WFC CCD Cross Talk

• SMOV WFC and HRC observations will be kept in separate proposals/visits to facilitate operations in case of unforeseen problems with the HRC backpowering.

• Cycle 17 calibration programs will overlap with SMOV and will provide further characterization of the instrument.

• We will include, as part of cycle 17 calibration plan, a “CCD optimization” program to investigate the benefits of operating the CCDs with a reduced clocking rate and clamp and sample scheme. The full impact on science operation (read noise, CTE, dynamic range, readout time) will be evaluated before making new options available for GO science.

• This program will be executed promptly if the noise characteristics of the default configuration are not satisfactory.


Conclusion• ACS-R successfully passed CDR• More integrated testing will start soon• STScI will be more involved in the future starting with the

ground testing

-----Original Message-----From: Weiss, Mike Sent: Thursday, October 04, 2007 10:33 PMTo: Smith, HsiaoSubject: Way to Go!

The ACS Repair just pulled off a miracle! You should all feelextremely proud of what you just accomplished, and I'm sure that you do.Please pass on to Ed, Pete and the entire team gratitude from not onlythe HST Program Office but from anyone in our Agency who may feel thatNASA no longer has the "Right Stuff." ACS Repair has just proved themwrong.

Superb effort on the part of all!

Mike

Documents

TIPS - October 18 2007 Updates on ACS-R Marco Sirianni October 18, 2007