Solar Probe Plus FIELDS V1234 Mechanical Pre-Ship Review May 26, 2017 David Glaser FIELDS Mechanical Engineer Space Sciences Lab University of California, Berkeley dglaser@ssl.berkeley.edu

Evidence of Acceptance by Developer QA Assembly of V1, V2, V3, and V4 Flight instruments completed See As-Built Flight Assembly Procedures V1234 passed Acceptance Vibration Tests – See SPF_ANT_070_RevE_V12_FM_Vibe_As-Run_Signed.pdf See SPF_ANT_070_RevF_V34_FM_Vibe As-Run_Signed.pdf

1. Storage and Integration Requirements Storage of the V1234 instruments requires ESD safety precautions. A connector saver will be on the preamp harness connector. The end of the whip clamp will have a short length of whip tubing, which must be grounded at all times. The instrument does not require purging or an inert atmosphere. The reference document SPF-ANT-PRC-021 V1234 Integration Procedure contains instructions for integration (incorporated into APL integration procedure) The reference documents SPF-ANT-ICD-001 V1 Antenna MICD, SPF-ANT-ICD-002 V2 Antenna MICD, SPF-ANT-ICD-003 V3 Antenna MICD, SPF-ANT-ICD-004 V4 Antenna MICD contains all relevant mechanical interface data. The most vulnerable parts of the V1234 instruments are the two small antennas are the thermal shield, the white painted areas, which are no-touch surfaces, and the whip end of the stub, which must be grounded at all times. Prior to I&T, the instrument will be stored mounted to bench fixtures, on a flow bench in the clean room. During I&T, when on the spacecraft, the V1234 instruments will almost always have their covers on. During I&T, red tag covers will only be removed for deployment tests and for observatory TVAC and EMC tests.

V1234 PSR Reference Documents (PDF) T8itle Document Number 1 V1234 Indentured Drawings List SPF_ANT_IDL_ 001 Rev E 2 All drawings from IDL V1234 FM Part Drawings 3 As-Built Assembly Procedures SPF_ANT_PRC_001-015, 017, 019, 020, 021 4 V12 FM Vibe Test Procedure As-Run SPF ANT 070 Rev E As-Run 5 V34 FM Vibe Test Procedure As-Run SPF ANT 070 Rev F As-Run 6 V1234 Integration Procedure SPF_ANT_PRC_021 7 V1234 MICD SPF_ANT_ICD_001, 002, 003, 004

Final Configuration Photographs Additional Photographs of the flight hardware are located at: https://spp.ssl.berkeley.edu/svn/FIELDS/05_Instruments/08_Preamp_Antennas/FIELDS%20Mechanical/Photos/Flight/V5/

V1 Final Configuration Photographs Additional Photographs of the flight hardware are located at: https://spp.ssl.berkeley.edu/svn/FIELDS/05_Instruments/08_Preamp_Antennas/FIELDS%20Mechanical/Photos/Flight/V5/

V2 Final Configuration Photographs Additional Photographs of the flight hardware are located at: https://spp.ssl.berkeley.edu/svn/FIELDS/05_Instruments/08_Preamp_Antennas/FIELDS%20Mechanical/Photos/Flight/V5/

V3 Final Configuration Photographs Additional Photographs of the flight hardware are located at: https://spp.ssl.berkeley.edu/svn/FIELDS/05_Instruments/08_Preamp_Antennas/FIELDS%20Mechanical/Photos/Flight/V5/

V4 Final Configuration Photographs Additional Photographs of the flight hardware are located at: https://spp.ssl.berkeley.edu/svn/FIELDS/05_Instruments/08_Preamp_Antennas/FIELDS%20Mechanical/Photos/Flight/V5/

Final Configuration Photographs – Red Tag Cover Additional Photographs of the flight hardware are located at: https://spp.ssl.berkeley.edu/svn/FIELDS/05_Instruments/08_Preamp_Antennas/FIELDS%20Mechanical/Photos/Flight/V5/

Final Configuration Photographs - Underside Additional Photographs of the flight hardware are located at: https://spp.ssl.berkeley.edu/svn/FIELDS/05_Instruments/08_Preamp_Antennas/FIELDS%20Mechanical/Photos/Flight/V5/

V1234 Acceptance Vibration Testing Note: There are 30 test graphs in the report. Only a representative sample of the data is presented here

Testing Summary Acceptance vibration tests performed per the requirements of 7434-9039_Rev_D_EDTRD_1108_Clean Addendum emails from Shelly Conkey Two antennas were tested at a time Random tests were notched around the first 3-4 modes of the thermal shields Triaxial Accelerometers were mounted as shown (selective channels used) Input Grms not to be more than 10% below un-notched spectrum Minimum acceleration (G2/Hz) not to be more than 14 dB below un-notched spectrum Pre- and post-test sine surveys performed Comparison Plots Generated to identify structural changes There were three testing anomalies, but they did not affect the final outcome of the test. All four antennas passed the acceptance vibration test

Accelerometers Principal Concern: Shield behavior Radiator Underside Stub Clamp Shield Principal Concern: Shield behavior All triax, but only selective channels used – focused on X and Y axes X-axis test Shield accel removed for 0 dB Random Stub accel proxy for shield accel Y and Z axes Shield accel left on Radiator accel provided indication of overall antenna integrity

FIELDS Acceptance Sine Vibration EDTRD Test Levels FIELDS Acceptance Sine Vibration Frequency X , Y, and Z Axes   (Hz) (g) 5 1.0 37 47 20.1 50 60 100 Sweep Rate: 4 oct/min Sine Test Levels FREQ(Hz) ASD(G2/Hz) 20.00 0.0028 35.00 0.15 60.00 70.00 0.023 200.00 250.00 0.23 600.00 2000.00 0.0062 12.49 Grms 1 min/axis Random Test Levels

Testing Anomalies In the X-axis ,V1 and V2 were slightly over tested in random vibration because the -6 dB and -3 dB tests were run without notching. Inspection showed no damage to the shields and APL (Shelly Conkey) reviewed the input levels and agreed that the amount of over testing was not concerning. In the Z-axis, V1 and V2 were slightly over tested, in random vibration, because of a loose accelerometer connector. Inspection showed no damage to the shields and APL (Shelly Conkey) reviewed the input levels and agreed that the amount of overtesting was not concerning. In the Y-axis, V3 was vibrated, in sine and random, with a missing Shield Isolator. No anomalies were seen in the sine signature, nor was damage found during inspection. The problem was identified following the 50% level sine test in the Z-axis. Testing was halted, the part was inserted into the antenna, and testing was resumed and completed.

Missing Shield Isolator Structurally, the isolator is required to help stiffen the shield against twisting

X-axis Configuration

Y-axis Configuration

Z-axis Configuration

V2 X-axis Sine Signature Pre and Post-Sine V2 Pre-Sine Changes in amplitude, and sometimes frequency, of the shield-stub, are normal Overlaying pre-and post- graphs is not too useful V2 Post-Sine

V1 & V2 X-Axis Notching Frequencies V1 Post-Sine Notching frequencies chosen from the combined min and max of both antennas V2 Post-Sine Notch 93-153Hz

Notching Frequencies Summary (All Antennas) V1 & V2 V3 & V4 X notch 93-153 Hz 107-159 Hz Y notch 93-125 Hz 100-140 Hz Z notch 108-153 Hz 111-153 Hz

V1 & V2 X-axis Random Notching from 93-153 Hz Input Grms -14 dB Line

V2 X-axis Sine Signature Pre & Post-Random No shield accelerometer

V2 Sine Signature Modes Summary

Random Input Grms Summary Un-notched input spectrum: 12.49 Grms Requirement: No more than 10% less: >11.24 Grms All inputs well within requirement Axis Prescribed Input with notch (Grms) As-Run Input with notch (Grms) Difference from un-notched input Notch > -14 dB? V12 X 12.42 12.29 -2% Yes V12 Y 12.44 12.36 -1% V12 Z 12.43 12.35 V34 X V34 Y 12.38 (V3) 12.44 (V4) 0% V34 Z 12.40 -<1%

Post-Test Hardware Inspections Accessible Screws Tight No discernible damage to instrument No cracks seen in bulkhead welds Passed Inspection V1 Yes V2 V3 V4

V1234 Acceptance Vibration Conclusions Pre- and post- frequency shifts meet requirements Random input levels meet requirements Post-inspection revealed no loose hardware, no damaged hardware, or any other anomalies All antennas passed the acceptance vibration test