1. Solar Probe Plus FIELDS Mechanical Pre-Environmental Review
David Glaser
Jose Fermin
Gayle Martin
Paul Turin
April 26, 2017

2. Attached Documents Vibration Test Plan SPF_AMT_070_V1234_FM_Vibe
All V1234 Antenna Assembly Procedures
References for those needing a design overview
SPP Fields ICDR Follow-On ANT Mech Design Final.pptx
FIELDS Final Peer Review Aug 2016.pptx

3. Agenda Engineering Overview Changes since CDR RFA summary Test Matrix?
Previous tests
Interface Verification
EM Qualification Test Results
I&T Flow
Contamination Control
Vibration Test Plan
Vibration Test Facilities
GSE
List
Special Test Requirements
Fixtures
Shipping Containers

4. Design Changes Since Aug. 2016 Peer Review
Stiffening Retrofits
Thermal Shield
Safety wire on outboard flexures
Welding protocol
Spacer and Shim Design
Whip Lead/Whip Clamp Joint
Conductive White Paint
Material changes (spring bushings, struts)
Preamp Harness Construction & Routing
Thermal Pigtail and Harness
Deployment Pinpuller Pigtail
GSE
Red/Green Tag Items

5. Retrofits to increase first mode
EM vibration tests with the larger radiator showed first mode ~85 Hz
Two gussets were added to make the structure stiffer
The first mode is now Hz, depending on the axis
Saddle-Preamp Box Gusset
Arm-Radiator Gusset

6. Thermal Shield Structural design has not changed
Safety wire
Structural design has not changed
Welding process has changed in the following ways:
Parts to be welded are sanded, and stored in dry nitrogen. They are exposed to air for the shortest time possible before welding.
Welding energy increased
Argon is flowed over the welding area, instead of just welding in air
Shields passed welding inspection by GSFC and APL inspectors
New Welds
Old Welds
Safety wire

7. Antenna Spacers Final Spacer Heights (Inches) Larger mounting feet
Oversized mounting hole for clocking adjustment
Spacer with 0.050” shim at nominal radial location
Shims in 0.025” increments
Hinge base now mounted to spacer with A bolts, each with R0.013” removed from the base of the threads (to allow for CTE slip)
4X A286 Bolts
Final Spacer Heights (Inches)
Description
Spacer Height
With 0.050” Shim V1
Min Shift
2.759
2.809 V2
Nominal
1.581
1.631 V3
0.638
0.688 V4
2.000
2.050
Sub-Spacer (APL)
Shim
TSA Mounting Pad

8. Whip Clamp-Whip Lead Joint
Crack
Moly-Nb Weld
Whip Clamp
Old Design with Moly TZM to Nb-C103 weld developed cracks
Whip Lead
New design has Nb-Nb weld and a screw joint
Nb-Nb Weld

9. Pinpuller Pigtail Copper tape electrical closeout on pinpuller
Power resistor on each pinpuller circuit
Electrical closeout on cabling and back of connector
White Painted Cover

10. Pinpuller Harness Each pinpuller in series with a power resistor,
Mounted in a box under the radiator arm

11. Thermal Pigtail B A Pigtail A – Heater to thermostat to pins
Pigtail B – RTD to pins
Pins located on bottom surface of radiator
Harness comes out of spacer loop, loops on underside of radiator, mates with pins B A

12. AZ-2000 White Painting Pin puller cover Preamp Radiator Support Arm
Four Parts have AZ-2000 Paint
All painted surfaces are flat areas, with some mild sheet metal bends included
Support Arm
Preamp Radiator
Arm Radiator
Pinpuller Cover
Painting was performed by GSFC, with a process approved by SPP management
Coupon Results:
a/e = .27/.88
Adhesion: Passed
Conductivity: Passed
Experience to Date
No cracking or chipping observed
Very small particles are being shed
Appear to be caused by incidental contact with parts
Will experiment with paint coupons and contact GSFC before the PER
Pin puller cover
Preamp Radiator
Support Arm
Support Arm Radiator

13. White Paint Particles Worst Case So Far
What we are typically seeing now

14. Deployment Spring Rollers
Material Changes
Changed from PEEK to Vespel SP1
Stub Lead Isolator Cap
Deployment Spring Rollers

15. List of GSE Items Name Description 1 Whip Clamp Interface Box
Grounding and signal injection into whip clamp, mounted to red tag box 2
Partial Deployment Tool
Thumb screw control of stub angle 3
Anti-Deployment Tool
Safety tool that prevents deployment latch from opening 4
Alignment laser (APL)
Inserts into whip clamp for I&T alignment 5
Whip simulator
~2 inch whip segment with wire from interface box 6
Short Test Whip
~2 ft whip segment for full deployment tests and pointing metrology 7
Long Test Whip
Full length, non-flight whip for clamshell alignment and partial deployment tests 8
Whip guide pin
1/16” dowel pin for alignment of whip and whip clamp safety wire holes 9
Pinpuller power supply
Power for pinpuller actuation 10
Pinpuller switch box
Control interface between power supply and pinpuller 11
Pinpuller reset tool
Reset pinpullers after actuation tests 12
IPA dropper bottle
For applying small amounts of IPA for lubrication of moly screws and sapphire parts

16. List of Red and Green Tag Items
Name
Description
Red Tag Cover
Protects entire instrument, has carrying handle; Removed for environmental and deployment tests
Red Tag Cover Mounting Blow
Mounted to instrument for entire I&T, allows easy installation and removal of cover
Red Tag Anti-Deployment Tool
Safety tool that prevents deployment latch from opening
Red Tag Flight Whip Serial Number Tags
Tied through the pin hole at the base of each whip
Green Tag – Flight Whips
Integrated very late in SC I&T

17. Red Tag Cover Carrying Handle Grounding Contacts
Electronics Interface Box

18. Acceptance Vibration Test
Test Procedure Document: SPF_ANT_070_V1234_FM_Vibe.pdf
Acceptance vibration tests will be performed at UCB/SSL per the requirements in _Rev_D_EDTRD_161108_clean and addendums provided by APL in messages
With manual notching around the first three vibration modes, to protect the thermal shields (suggested and approved by APL)
Two antennas will be vibrated at once
Accelerometers to be mounted as shown in next slide
Shield accelerometer will be used for mode characterization and removed for full level vibration
Pre-and post-test sine survey before and after sine strength and random tests
Comparison plots will be generated to identify any mode changes.

19. Test Procedure
Written by UCB/SSL (Document SPF_ANT_070_V1234_FM_Vibe)
Consistent with SPP EDTRD ( _Rev_D_EDTRD_161108_clean) and addendums provided by APL in messages
Acceptance Levels and Durations
Sine survey/Sine strength/Random
All 3 Axes
Unit unpowered during testing
Electrical Functional Test before and after test
Vibration Fixture
Designed and built by UCB/SSL
Simple Plate
SSL Vibration Facility
No technical problems
Facility Ready for use
Personnel able to support test
Cleanliness
Vibration Facility in-house at UCB/SSL (no transportation required)
Antennas to be bagged during testing
Overtest Precautions
Manual notching of first three modes (random only)
2 control inputs (averaging inputs)

20. All resources ready Summary Concerns
Test Specifications, Procedure, Vibration Fixture, Vibration Facility, Personnel
Test procedure in signature cycle at UCB/SSL
Concerns
None

21. Vibration Test Configuration
Accelerometer Locations

22. Sine Strength Test Levels
Frequency (Hz)
Level (G) 5
1.0 37 47
20.1 50 60
100
Sweep Rate
2 oct/min

23. Acceptance Random Test Levels
FREQ (Hz)
ASC (G2/Hz)
20.00
0.0028
35.00
0.15
60.00
70.00
0.023
XX-YY-ZZ
.023
0.001
200.00
250.00
0.23
600.00
0.0062
XX-YY-ZZ Grms
1 min/axis
EDTRD Spectrum
Notched Spectrum -14 dB
Notch shall not go below -14 dB from EDTRD Spectrum
Overall Grms shall not go >10% below EDTRD Spectrum

24. Manual Notching for Shield Modes
Pre-random sine signature to ID first three modes (tailored to each axis)
Program notching (-14 dB)
Low level random tests to verify/adjust notching
Remove shield accel and full level test with notching

25. Notching Example from EM Vibe – Protoflight Levels
Notching Spectrum
EDTRD Spectrum
FREQ (Hz)
ASC (G2/Hz) 20
0.0055 35
0.300 60 70
0.045
X-Y-Z
.045
0.002
200
250
0.450
600
2000
0.0123
X,Y,Z Grms
1 min/axis
FREQ(Hz)
ASD(G2/Hz)
20.00
0.0055
35.00
0.30
60.00
70.00
0.045
200.00
250.00
0.45
600.00
0.0123
17.49 Grms OA
1 min/axis

26. Manual Notching for Shield Modes (EM Test)
Requirements
Notching effectively reduces shield modes
Notch not less than -14 dB
Total Grms not more than 10% less than EDTRD specification

27. Flight Hardware PhotosV1 V1 V4 V4