pacs ihdr mpe 12/13 november 2003 system engineering 1 pacs ihdr model philosophy, budgets,...

System Engineering 1

PACS IHDR MPE 12/13 November 2003

PACS IHDR

Model Philosophy, Budgets, Interfaces and

IID-B

Reinhard Katterloher



Configuration and Development of PACS Instrument Models

• Flight Instrument consists of 1 cryogenic FPU, 4 electronics boxes (units) at ambient temperature, 1 set of WIH

• CQM+AVM Instrument consists of 1 cryogenic FPU, 4 electronics boxes (units) at ambient temperature, 1 set of WIH

• Flight Spare philosophy demands 1 cryogenic FPU (which is the refurbished CQM unit), and electronics spare kits

• Development program, performance verification and environmental qualification of Units is taken care by the individual manufacturers

• For each Unit a dedicated Development and Test Plan (covering all AIV activities on Unit level) is issued and enforced

• AIV of the different models on instrument level starts after delivery of the Units to MPE



Model Philosophy (deliverables to ESA are marked in blue)

Models/ Units

AVM CQM PFM FS QM

FPU STM CQM PFM CQM

refurb. -

DPU AVM AVM PFM spare

kit QM

SPU AVM AVM PFM spare

kit EM

DECMEC AVM EM PFM spare

kit QM+

BOLC BOLCSIM QM1 PFM spare

kit QM2

WIH AVM AVM PFM - QM

EGSE AVM AVM FM FM -



CQM-FPU and AVM-WE characteristics compared to PFM

• FPU CQM is a nearly FM representative FPU Unit Complete optics, all mechanisms, all sensors Blue spectrometer array: 12 modules instead of 25 Red spectrometer array: 11 modules instead of 25 Blue photometer array: 8 sub-arrays (2 near perfo.) of 8 Red photometer array: 2 sub-arrays (1 near perfo.) of 2• AVM electronics is built with commercial grade components, no

redundancy, DECMEC, BOLC and SPU are not form fit with FM

• CQM wavelength calibration program cannot be executed to the same accuracy as planned for FM due to schedule limitations

• EMC tests during CQM ILT and on system level (EQM) planned



Functional Properties of Units (deliverables to MPE)

Unit Model status

FPU STM (mass, size, thermal, ext. alignm.)CQM (full repres. of FM, 50% Ge-arrays)PFM (full flight representative)

delivered

DPU AVM (functional repres. of FM, FFF)PFM (nom and red part)QM (functional repres. of FM, for ILT FS)

delivered

SPU AVM (functional repres. of FM)EM (functional repres. of FM, for ILT FS)PFM (2 identical boxes nom/red)

delivered

DECMEC

AVM Simulator (supports electrical + S/W performance verification)EM (1MEC+2DEC)QM (1MEC+1DEC, upgrd. requ. for ILT FS)PFM (2MEC+2DEC in 1 unit)

delivered

BOLC BOLC Simulator (supports electr.+S/W ver.)QM1 (supports FPU ILT performance verif.)QM2 (full QM, for initial FM, for ILT FS)PFM (full flight representative)

delivered



Combination of Units during ILT Phases

ILT phase

AVM CQM PFM FS

FPU STM CQM PFM CQM refurb.

DPU AVM AVM PFM QM

SPU AVM AVM PFM EM

DECMEC AVM EM PFM QM+

BOLC BOLCSIM QM1 QM2

(PFM) QM2

WIH AVM AVM PFM QM

EGSE ILT ILT ILT ILT



FPU Schematic and Interfaces

2 bolometer arrays at 0.3K

Electrical I/F

optics

structure

int. harness

FPU

\m soffice\grafiken\IID R \PAC S-FPU -schem e-IH D R .cdr

Optical I/F to Telescope Beam

ThermaI I/F toCooling Syst.S/C

Mechanical I/Fto Optical Bench

temperaturesensors

1.7K Level 0

2 filter wheeldrives and

position sensors

chopper drive and

position sensor

2 calibrationsources

heater/sensor

distributionboards

connectors

2 photoconductor arrays

CRE

grating drive,grating position sensor,

launch lock device

3He sorption cooler and

cryo electronics

Electrical I/F

Optical I/F Alignment Cubeto outside CVVAlignment Tool

InstrumentWarm

Electronics

Spacecraft

Mechanical I/FSVM Panel

2 bolometer arrays at 0.3K

Electrical I/F

optics

structure

int. harness

FPU

\m soffice\grafiken\IID R \PAC S-FPU -schem e-IH D R .cdr

Optical I/F to Telescope Beam

ThermaI I/F toCooling Syst.S/C

Mechanical I/Fto Optical Bench

temperaturesensors

1.7K Level 0

2 filter wheeldrives and

position sensors

chopper drive and

position sensor

2 calibrationsources

heater/sensor

distributionboards

connectors

2 photoconductor arrays

CRE

grating drive,grating position sensor,

launch lock device

3He sorption cooler and

cryo electronics

Electrical I/F

Optical I/F Alignment Cubeto outside CVVAlignment Tool

InstrumentWarm

Electronics

Spacecraft



Mechanical interfaces of FPU – OB and WE – SVM

• The PACS FPU is mounted on the OB with 3 CFRP feet• The mechanical Interface is fully described in the drawing “PACS-KT-ICD-0000W1 issue 27 draft dated 04-07-2003”• The FPU ICD drawing is annex to IID-B

• The bolting scheme of BOLC QM to SVM is not identical with FM

• The mechanical interfaces of other WE FM boxes to SVM are given in the relevant PACS Interface Control Drawings

• WE FM ICDs are annex to IID-B• Change requests are issued for WE AVM boxes



Thermal Budget and Interface FPU - S/C cryostat

• FPU requires two temperature levels- level 0 at nominal 1.7K (max. 1.75 K accepted)- level 1 around 4K (max. 5.0 K accepted)

• Other temperatures inside the FPU are produced autonomously (2.2K blue array/ 0.3K bolometers)

• Thermal coupling to cooling level 0 via 4 heat straps• Thermal coupling to cooling level 1 via 3 heat straps• FPU is thermally decoupled from OB by CFRP feet• Thermal loads and final heat fluxes are calculated

using the PACS TMM combined with the cryostat TMM



Steady State Heat Dissipation (table from PACS TMM)



Harness Interface FPU–WE–S/C and Electrical Budget

• Harness is specified in PACS-MA-SP-001-V3.2, annex to IID-B It consists of

- total inside CVV: 1060 wires + 255 shields

- total outside CVV: 1060 wires + 255 shields + 15 overshields

- Warm Interconnect Harness (specs. given in PACS-CL-RS-010)

• Power consumption of WE see separate table

• Science data rate in PACS prime mode is 130 kbps max (120 kbps average per day)



Power Consumption on SVM (present allocation is 120 W, CR-0033_V3 pending, demand for LCL class

III)

Table of maximum average power and short and long peak power demand is provided in IID-B CR-0033_V3



Mass and Size of Instrument Units

Project code Instrument unit Dimensions (mm)length x width x

height

Nominal mass (kg)

FPFPU Cold focal plane unit See configuration drawings annex IID-B

73.6

FPDECMEC Detector control and mechanism control unit

EM 560x318x304FM 560x318x305

TBC23 (TBC)

FPBOLC Bolometer and cooler control unit

QM 328.5x300.2x314.3FM 382.5x289x333.5incl. connect. backshell 499.5x289x376.9

TBC15.35

FPDPU Digital processing unit 274x258x197 including fixation feet240x258x197 exclud.f.f.

6.62

FPSPUnom.+redu. stacked

Signal processing unit AVM 280x240.5x350FM 270x221x186

TBC7.0

FPWIH Warm interconnect harness

Length AVM 2000Length FM 1300/1500

1.5TBC

Total mass FM (allocation 130 kg) 127



Current IID-B Status

• Status of open CRs submitted or still to be written will be given under topic PA/QA

• Status of open RFWs submitted or still to be written will be given under topic PA/QA

• Lot of figures and few tables need to be replaced according to progress in instrument development and have to be included in the very next version of IID-B (many of the figures are ready for submission)

• Missing figures, drawings and all text additions can be expected from PACS within the next two weeks



Urgent Pending Activities w.r.t. Documentation

• Update of IID-B has highest priority• Next issues of AIV Plan and Test Plan are due (PCD draft 7 up to date)• Definition of the optimized ILT test sequence and consolidation of

test steps need further technical discussions• Definition of detailed test procedure for the CQM+AVM ILT in

progress already, issueing of the document Test Plan will be started immediately after AIV Plan is completed

• Selection of „building blocks“ out of the ILT program for the EQM test program has to be started soon (test steps adapted to EQM constraints)

• Approval of RFW0003 expected soon, qualification program of black paint needs to be finished because manufacture of FM structure has started

pacs ihdr mpe 12/13 november 2003 system engineering 1 pacs ihdr model philosophy, budgets,...

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