1 PFP Peer iCDR 2011/5/11 Particles and Fields Package (PFP) Peer Instrument Critical Design Review STATIC Mechanical Gregory Dalton Gregory Johnson UCB-SSL 2 PFP Peer iCDR 2011/5/11 STATIC Mechanical Overview Assemblies and Features Materials Analyzer Construction Attenuator Construction Time of Flight Section MCP Construction Purge Construction HV Tower Electronics Board Stackup Electronics Box Construction Mounting and Interconnects Analysis Mass Future testing 3 PFP Peer iCDR 2011/5/11 STATIC Status Drawings 100% complete Fabrication in process Testing Preliminary Acoustics, Vibration on TOF and Electronics Box All PDR RFAs addressed 4 PFP Peer iCDR 2011/5/11 STATIC Assemblies and Features Analyzer Anode/MCP Electronics Attenuator/ Cover Release PFDPU/S-C Connectors Mounting Feet Time of Flight HV Tower Connector Access Panel 5 PFP Peer iCDR 2011/5/11 STATIC Materials and Construction Standard UCB Construction: Machined/Etched Parts 6061-T6 Aluminum 2024-T8 Aluminum 544 Bronze 303 Stainless Steel Delrin AF, PEEK 450G, Vespel SP-1/3 (high voltage isolation materials) BeCu springs Finishes Alodine Anodized Gold Plating Ebonol C, Black Chrome, DAG-213, Black Electroless Nickel with Teflon Thermal Treatments Blankets (LM supplied) Thermal Taping (LM supplied) Long lead Items MCP Carbon Foils/Carriers TiNi P5 Pin Pullers 6 PFP Peer iCDR 2011/5/11 STATIC Analyzer Construction Inner Hemisphere Outer Hemisphere Deflectors Aperture Ring Dome Mount Bottom Deflector Mount Upper Deflector Mount Spider Plate & Exit Grids Release Housing Cover Release Mechanism Attenuator Mechanism Hemisphere Cover Attenuator 7 PFP Peer iCDR 2011/5/11 Cover Release Mechanism Cover Closed Cover Open TiNi P5 Pin Puller Inner Slide Spring Plunger Burp Spring Retraction Spring Attenuator Latch Cover Seal Burp Spring: designed to relieve N2 at 5psi. Holds cover closed during vibration Safety Switch 8 PFP Peer iCDR 2011/5/11 Attenuator Cover Closed Cover Open, Attenuator Down Cover Open Switch Cover Open, Attenuator Up Cover Stroke: 0.220 Aperture stroke: 0.225 9 PFP Peer iCDR 2011/5/11 Attenuator Attenuator Slide SMA Spring Block Switch Assembly Attenuator Down Attenuator Up Attenuator Design: 30g moving mass 2.17 N per wire, redundant wires in both directions Must overcome 0.51 N switch spring force to actuate attenuator (in 1G) 8x SMA force margin 25% SMA wire over travel to ensure actuation 10 PFP Peer iCDR 2011/5/11 STATIC Purge Operation N2N2 5psi N 2 purge pressure N 2 purge path 1/8 NPT Cole Palmer compression fitting and right angle purge block. Viton O-Rings 11 PFP Peer iCDR 2011/5/11 STATIC MCP Assembly No significant design changes since PDR ItemValue Measured Force/Leaf (lb)0.22 Number of Leaves200 Total Spring Force (lb)44 Clamped Mass (g)43 Required Clamping Force (lbs, 100g loading, =0.2) 23.7 Force Margin1.86 Force Margin, MCP Springs 12 PFP Peer iCDR 2011/5/11 STATIC Electronics Board Stackup LVPS Anode Preamp TDC 15kV Sweep/ Deflector Digital MCP Cover Digital pigtails to MDM on Preamplifier Pulse to Anode FPGA 13 PFP Peer iCDR 2011/5/11 STATIC Electronics Box Construction HV Enable LVPS to PFDPU Digital to PFDPU HV to Deflectors Airborne WTAX Huber MMBX Coax Sweep HV 14 PFP Peer iCDR 2011/5/11 STATIC Mounting, Harness, and Purge N 2 Purge Connection Harness Connectors 15 PFP Peer iCDR 2011/5/11 STATIC TOF Acoustic Testing Tested 3 Time of Flight Units at Wiley Labs (El Segundo, CA) Configuration included: E-Box with Preamp and TDC Boards HV Tower, MCP Stack with Dummy MCPs, Dummy Analyzer Closeout Ran proto-flight levels for 90s each No mechanical damage found during post-acoustics inspection Frequency (Hz)Protoflight SPL (dB) One start frame slipped during acoustics. This issue has been addressed by redesigning the start frame. 16 PFP Peer iCDR 2011/5/11 STATIC TOF Vibration Testing Tested 3 Time of Flight Units Tested Z and Y Axes random vibration, 1/4G pre and post sine surveys Configuration included: E-Box with Preamp and TDC Boards HV Tower, MCP Stack with Dummy MCPs, Dummy Analyzer Closeout Unit IDFn,z (Hz)QzFn,y (Hz)Qy SN SN SN Pre-Random 1/4G Sine Sweep Response: Freq (Hz)Protoflight Level (g^2/Hz) GRMS9.59 Random Vibration Spec: 17 PFP Peer iCDR 2011/5/11 STATIC TOF Vibration Testing Post-Vibration Inspection: One unit had damage to HV Connection Tabs, which will be addressed with tab redesign No frame slippage seen. 18 PFP Peer iCDR 2011/5/11 ItemOldNewComments Start Foil Frame Better Clamping Design Easier Handling for Assembly High Voltage Tab Lower Stress Concentration Improved Compliance Improved Assembly Order STATIC TOF Design Changes New position of HV Tab allows tab to be added as final assembly step. 19 PFP Peer iCDR 2011/5/11 STATIC ESA Middle Grid Assembly Middle grid ground strip Electrical isolation via clearance slots Final assembly with outer grid 20 PFP Peer iCDR 2011/5/11 STATIC Mechanical Analysis Aperture Modal Analysis Assumptions: Remote mass to simulate Attenuator, TOF, and Electronics Fixed interface at mounting feet Results: 217 Hz First Mode 14% Mass Participation Electronic Box Wall Stress: Required shielding of 0.1 Low resulting stress in E-box parts Aperture is stress limiting part 70G static loading 21 PFP Peer iCDR 2011/5/11 STATIC Mechanical Analysis Aperture Static Load Analysis Assumptions: 350g remote mass to simulate attenuator Fixed interface to Time of Flight Housing 70G static load (Miles Equation Fn=221Hz & Q=20) 8 Lb load from cover mechanism Results: 22 PFP Peer iCDR 2011/5/11 Cover Deflection and Load Burp Spring Plunger Cover Clamp Radially constrained, 0.010 gap Aperture under 70G radial load 8 lbf preload on Analyzer Cover 23 PFP Peer iCDR 2011/5/11 STATIC Mass Budget Electrostatic Analyzer Assembly Anode Assembly Time of Flight Assembly Electronics (Including Boards) Mechanical Misc. (Housing, Fasteners) CBE STATIC Instrument Mass Allocation from MAVEN_PF_SYS_002V Resources MARGIN35%13% CBE mass based on a combination of: Solid model with realistic mass properties Measured STATIC prototype board mass Measured mass of heritage parts and boards 24 PFP Peer iCDR 2011/5/11 Future Plan Carbon Foil vibration test End of June Attenuator Life Test End of June Concurrent assembly of detector for Calibration Chamber Testing End of June N2 Purge Test Exercise Manipulator Vibration test for final frame design and structural verification with electronic mass dummies Mid July ETU Testing Beyond ETU Flight fabrication in August Black Nickel coating vendor Issues