Dominion Radio Astrophysical Observatory DVA-1 Reflector Development Timeline Gary Hovey NRC-HIA Dominion Radio Astrophysical Observaotry

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 2 of 20 Contents Reflector Project Scope Project Phases and Milestones Key Objectives, Outcomes and Issues by Phase Conclusions

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 3 of 20 DVA-1 Reflector Project Scope What are the DVA-1 Goals Pertaining to the Reflector? Performance Requirement –Reflecting surface that meets maintains it shape over specified operating conditions (wind, temp, gravity). Cost Requirement –Demonstrate its affordable and has superior cost/performance. –Prototype can be built with available budget and meet performance requirement. Schedule Requirement –Built within the timeframe of PrepSKA? –Built within the timeframe agreed upon in advance? –Built roughly within the timeframe agreed upon?

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 4 of 20 Scope Issues Budget, resources and schedule are limited. Requirements are in conflict and need to be prioritized. What are we designing for? –Schedule? Which schedule? SKA, Hard or soft deadline? –Cost? –Performance?

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 5 of 20 Proposed Reflector Scope Requirements Requirements in Priority 1.Performance: Must meet SKA performance specifications 2.Cost: Must be within DVA-1 budget and demonstrate SKA cost/performance 3.Schedule: Must be adapted to fit performance and cost requirements.

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 6 of 20 Proposed Responsibilities and Tasks What does the reflector work include? Reflector performance and cost key drivers. Reflector performance and schedule dependent strongly (mainly/mostly) on back-up structure and feed. Propose reflector consists of: Surface, backup structure, feed & sub-reflector support. These need to be considered together as an integrated whole. Reflector Interfaces: indexer/receiver box, sub-reflector and turret frame.

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 7 of 20 Key Reflector Requirements/Specifications Performance –Reflector shape and feed/sub-reflector support specs –Dynamic tolerances specs as function wind, gravity and temperature. –Mount interface specs. Cost –Available budget –Available infrastructure –Available resources and definition of project scope Schedule –Clear goals and deliverables with achievable deadlines These need clarity to make progress

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 8 of 20 Proposed Reflector Project Phases Four Phase Project –Concept Design Phase -> Concept Design Review –Preliminary Design Phase -> Preliminary Design Review –Detailed Design Phase -> Critical Design Review –Fabrication Phase -> Fabrication Acceptance –Test Phase -> Project Complete Clear specifications, objectives and deliverables for each phase are needed to ensure performance, cost and schedule requirements.

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 9 of 20 Reflector Concept Design Phase Objective: Define project based on feasible design concepts. Duration: 2-3 months once requirements/specifications set. Outcomes –Concept design Based mainly on estimation, calculation and simulation Feasible design that meets overall performance, cost and schedule requirements Risk items identified –Baseline project plan including: Initial WBS, costs and schedule Risks: technical, cost, schedule Plan to address risks

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 10 of 20 Key Concept Design Issues Need to define surface shape specifications –What diameter: 12m or 15m? At CoDR? Now?? –What antenna pattern? What is optimized? Aeff Aeff/Tsys Near and far sidelobe response Symmetry, stability, uniformity –Need to understand calibration, imaging and computing impact Select or defer backup structure approach to prelim design? To what extent are PAFs considered? Need clarity on design goals: Performance, budget, schedule? Need clarity on available budget and constraints. CoDR can’t be done without these issues resolved.

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 11 of 20 Reflector Preliminary Design Phase Objectives –Sketched out design in non-risk areas –Detailed design/studies in riskier areas Duration: 2-3 months once CoDR complete Outcomes needed –Preliminary design Materials selected and their performance known Risk items addressed Based on calculation, simulation and measurement Technical risk low –Updated project plan Schedule and cost risk quantified Detailed design plan well defined Fabrication and test plan well understood.

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 12 of 20 Reflector Preliminary Design Activities Material studies/testing Finalize composite materials Select/refine backing structure Refine feed support Possibly, procure mold(s) as soon as surface defined.

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 13 of 20 Reflector Detailed Design Phase Goal: Fully specify design, as well as, fabrication and test plans Time needed: 4-6 months once PDR complete. Outcomes needed –Fully specified design. –Risks low: Costs, schedule well determined. –Detailed fabrication and acceptance plan(s) Activities, WBS, deliverables, costs and schedule –Detailed test plan

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 14 of 20 Detailed Design Issues This is mainly a fill in the blanks phase. To what extend do we validate dynamics (wind, temp, resonance)? Schedule vs cost risk How much design margin is carried? –Material cost vs performance and schedule risk Can molds be ordered before CDR? Schedule vs cost risk

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 15 of 20 Reflector Fabrication Phase Objectives: fabricate/assemble reflector, back-up structure, feed/sub support. Duration: 6-9 months (not including setup/procurement) Outcomes –Sub-assembly fabrication and acceptance complete Reflector surface Backup structure Feed/sub support –Assembly complete and ready for test on mount

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 16 of 20 Fabrication Phase: Issues Lead time for procurement of materials Lead time for preparing site for fabrication What facilities on-site can be used? Site regulation and procedure issues Schedule and cost overheads due to the location Costs magnified if project delayed Clean-up costs

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 17 of 20 Reflector Test Phase Objectives: Determine reflector assembly performance Duration: 2-4 months Outcomes Reflector metrology tests –Over gravity, temp, wind Simulated antenna pattern response Measured antenna pattern and holography measurements

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 18 of 20 Reflector Test Phase Issues Separating dynamic reflector performance from the mount. Testing over temperature extremes difficult Testing over wind conditions/requirements difficult Schedule and cost overheads due to the location

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 19 of 20 Timeline Q2Q3Q4Q1Q2Q3Q4Q1Q2 Concept Design Preliminary Design Detailed Design Fabrication Reflector Testing Buy Molds

DVA-1 Meeting Washington 15 April 2010 DVA-1 Reflector Development Timeline G. Hovey 20 of 20 Conclusions Reflector project reasonably complex. Need to better define scope and responsibilities Number of requirements/issues need to be address/resolved. Project plan, design phases and reviews needed These would inform key decisions.