PACS IBDR 27/28 Feb 2002 PACS PI Summary1 Where we are and where to go… A. Poglitsch MPE

PACS IBDR 27/28 Feb 2002 PACS PI Summary2 PI’s Survey – neither complete nor unbiased What have we achieved? Where do we see our problems/shortcomings? How should we move on?

PACS IBDR 27/28 Feb 2002 PACS PI Summary3 Achievements Stable instrument design –design of and interfaces between all subunits consistent optics incl. alignment structure (mechanical incl. transfer loads, thermal) electrical (warm electronics units + cryogenic electronics) on-board software architecture –interfaces with S/C interfaces and requirements defined from PACS side agreement on science data rate, in line with PACS needs

PACS IBDR 27/28 Feb 2002 PACS PI Summary4 Achievements System engineering –communication/interaction between system engineers and subunit engineers systematically improved since IIDR regular update on design, development, interfaces active participation in subunit reviews dedicated working groups for critical developments –interaction with S/C contractor through technical meetings discussion of interfaces, budgets, system test plan possible basis for rapid, non-bureaucratic problem solving

PACS IBDR 27/28 Feb 2002 PACS PI Summary5 Achievements Demonstration of critical technical developments –photoconductor arrays work – as far as tested – to spec –CREs are operating ~ to spec with prototypes of cryoharness and DEC –grating actuation and position readout tested to spec –manufacture of grating in time shown feasible –bolometer array and cryogenic multiplexer/buffer are operational –0.3 K cooler operates with high cooling power margin –on-board signal processing achieves compression of (simulated) raw detector data into available TM bandwidth

PACS IBDR 27/28 Feb 2002 PACS PI Summary6 Achievements Schedule –consistent schedule for subunit and instrument manufacture, assembly, and tests –reasonable margin for most activities –~ compatible with latest schedule “goal” from Project –critical path identified

PACS IBDR 27/28 Feb 2002 PACS PI Summary7 Problems Schedule –bolometers on critical path (for QM) –margin for photoconductors small –margin for PACS test cryostat small –margin in test schedule small, QM test plan already at the minimum acceptable level –delay of QM programme would delay FM programme

PACS IBDR 27/28 Feb 2002 PACS PI Summary8 Problems Technical (potential) –quantitative optical measurement of bolometers outstanding –operation of photoconductors with CREs not demonstrated –grating drive bearings are SPF for spectroscopy, full qualification outstanding –operation of BOLA JFETs at 60 K to be demonstrated

PACS IBDR 27/28 Feb 2002 PACS PI Summary9 Problems Interfaces with S/C –missing input on telescope/cryostat straylight –missing thermal analysis at system level –alarming state of requirements implementation by S/C (cryoharness, 2 K straps for 0.3 K cooler) Communication –communication between “triangle” PACS/Project/Prime not efficient –communication within Alcatel/Astrium/Alenia consortium not efficient

PACS IBDR 27/28 Feb 2002 PACS PI Summary10 Problems Excessive workload from non-essential tasks –system and subunit engineers see a tendency to get overloaded with “formal” documentation writing (“Do you want bolometers, or do you want paper?”) –with upcoming hardware phase and a tight schedule the PACS consortium cannot afford to waste resources on non- productive work

PACS IBDR 27/28 Feb 2002 PACS PI Summary11 Suggestions for the Future Communication between PACS, Project, Prime –we can only be successful if we all work together –we have to establish procedures for non-bureaucratic interaction of the technically competent persons on technical problems/issues with rapid top-level authorisation such that agreements are binding for all parties –technical or managerial meetings make sense, but only if they are properly prepared by all participants –to limit the workload, critically review the documentation requirements from Project side and reduce them to the technically necessary

PACS IBDR 27/28 Feb 2002 PACS PI Summary12 Suggestions for the Future Communication within the PACS consortium –we have to continue and finish what we started to improve after the IIDR, i.e. bring everyone (e.g. IAC/CRISA) to the same level as reached for some (e.g. IFSI/Gavazzi) –strengthen and support the interaction of our new electronics system engineer with all subunit engineers –support of PA/QA activities by all partners –extend the interaction between instrument people and ICC people, particularly for on-board S/W design (AOT design, on-board data processing)

PACS IBDR 27/28 Feb 2002 PACS PI Summary13 Suggestions for the Future Schedule –with a tight schedule and a not fully demonstrated, but essential component (bolometer) on the critical path and another one (photoconductor/CRE) not too far from it, we need to look into alternative scenarios to ensure the instrument delivery date –prioritise instrument test sequences (which to sacrifice first, if necessary) –consider start of instrument tests with bolometer STM and integration of bolometer QM immediately before cryovibration at CSL to reduce delay

PACS IBDR 27/28 Feb 2002 PACS PI Summary14 Final Words “Problems? I don’t call that problems, I call it tasks!” (M. v. Berg)