SSPP-TEV-035 HITCHHIKER ADVANCED CARRIER EQUIPMENT RANDOM VIBRATION TEST PLAN BASIC RELEASE MARCH 1997 GODDARD SPACE FLIGHT CENTER GREENBELT, MARYLAND

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1 HITCHHIKER ADVANCED CARRIER EQUIPMENT RANDOM VIBRATION TEST PLAN SSPP-TEV-035 BASIC RELEASE MARCH 1997 GODDARD SPACE FLIGHT CENTER GREENBELT, MARYLAND PREPARED BY: 5050 POWDER MILL ROAD BELTSVILLE, MD 20705

3 REVISION LOG REV DESCRIPTION INITIATED BY APPROVAL

4 1.0 SCOPE This test describes the materials and procedures needed to perform the system level workmanship acceptance vibration testing for the Hitchhiker Advanced Carrier Equipment (ACE). 2.0 APPLICABLE DOCUMENTS HHG GEVS-SE Hitchhiker Customer Accommodations & Requirements Specification (CARS) General Environmental Verification Specification for STS & ELV Payloads, Subsystems and Components 3.0 TEST ARTICLE DESCRIPTION The test article is the HH ACE (Figure 1.0) which consists of the following components: Component Weight (lbs) LAP LAP Beam Brackets HRIU Subassembly 66.0 PDU 45.0 HCU # HCU Featherweight Box 5.0 DSU Featherweight Box 3.0 Cabling 20.0 Cable Support Brackets 2.0 Total About 250 lbs 4.0 OBJECTIVE The objective of this test is to subject the ACE to a random vibration test at flight acceptance levels to verify the hardware s reliability in the space flight environment. In addition, sine sweeps are to be performed to obtain data on the resonant frequency of the assembly. 5.0 TEST DESCRIPTION Sine Sweep: In order to obtain data on the resonant frequency of the ACE, seven (7) triaxial accelerometers are required to be mounted in the locations described in Figure 1.0. In addition, a facility control accelerometer shall be mounted on the vibration table near the XYZ LAP Beam Bracket. Transfer function plots are required for all test channels and the in-axis control channel. 1

5 Random Vibration: This test satisfies the flight workmanship acceptance requirements. The testing levels are shown in Table 1. This test uses the same instrumentation as defined for the sine sweep. Acceleration spectral density plots are required for all test channels and the in-axis control channel. Vibration cross-talk shall be measured and out of axis levels shall not exceed peak ASD requirements. The test tolerances are presented in Table 2. ACE Test Article and Accelerometer Locations Figure 1.0 2

6 Table 1 Acceptance Random Vibration Specification from HH CARS For a 250 lb Component Frequency ASD Level (G 2 /Hz) (Hz) Acceptance db/oct db/oct Overall G rms Note: Test duration is 60 seconds for each axis. Table 2 Test Tolerances Sinusoidal Vibration Amplitude ± 10% Frequency ± 2% Random Vibration RMS Level ± 10% Power Spectral Density ± 3 db 5.1 TEST FACILITY The test will be conducted in the GSFC Engineering Services Division (ESD) Vibration Facility. 5.2 TEST APPARATUS CONFIGURATION Figure 1.0 shows the test article and its associated axes. The interface plate to attach the test article to the shaker table will be the Hitchhiker Adapter Beam vibration fixture and provided by Code 740/NSI. The triaxial accelerometers will be provided by NSI. Tests in the X axis will be conducted on the vertical (thrust) shaker table. Tests in the Y and Z axes will be conducted on the lateral shaker table. 5.3 TEST ARTICLE HANDLING The test article is to be handled under normal laboratory procedures. All handling of white painted surfaces shall use latex gloves. Because of ESD sensitive components, ESD handling procedures must be used. Llumalloy shall be used to protect the ACE during overnight hours. The handling of the test article will be done by overhead crane using GSFC Code 740 provided lifting equipment. There are no unusual temperature, humidity, or cleanliness requirements for this test. An acceptable laboratory environment is sufficient. 3

7 5.4 FUNCTIONAL TESTING At the conclusion of each vibration test, the ACE avionics will undergo a short functional test prior to removal from the vibration table. The test will take approximately 90 minutes. 6.0 TEST PROCEDURE 6.1 RANDOM VIBRATION, X AXIS Perform a short functional test after installation to the table Conduct a 1/4 G sine sweep, Hz at 2 oct/min. Review real-time plot. Approval of test engineer required to continue Conduct a 1 G sine sweep, Hz at 2 oct/min. Review real-time plot. Approval of test engineer required to continue Conduct a random vibration run at full level per Table Conduct a post sine sweep at 1 G, Hz at 2 oct/min. Review real-time plot. Approval of test engineer required to continue Perform a short functional test prior to removal from the table. 6.2 RANDOM VIBRATION, Y AXIS Conduct a 1/4 G sine sweep, Hz at 2 oct/min. Review real-time plot. Approval of test engineer required to continue Conduct a 1 G sine sweep, Hz at 2 oct/min. Review real-time plot. Approval of test engineer required to continue Conduct a random vibration run at full level per Table Conduct a post sine sweep at 1 G, Hz at 2 oct/min. Review real-time plot. Approval of test engineer required to continue Perform a short functional test prior to removal from the table. 6.3 RANDOM VIBRATION, Z AXIS 4

8 6.3.1 Conduct a 1/4 G sine sweep, Hz at 2 oct/min. Review real-time plot. Approval of test engineer required to continue Conduct a 1 G sine sweep, Hz at 2 oct/min. Review real-time plot. Approval of test engineer required to continue Conduct a random vibration run at full level per Table Conduct a post sine sweep at 1 G, Hz at 2 oct/min. Review real-time plot. Approval of test engineer required to continue Perform a short functional test prior to removal from the table. At the completion of all testing, the test article will be removed from the shaker table. The test article will be returned to Code 740 for a thorough visual inspection and functional testing. 7.0 TEST ORGANIZATION The test will be conducted with support from GSFC Code 754 and NSI personnel. 8.0 TEST SAFETY All tests shall be conducted in accordance with the GSFC Standard Safety and Environmental Procedures and with no unacceptable risks or hazards to the personnel or test article. Note that crane operation safety procedures will be in effect. 9.0 TEST HALT/FAILURE CRITERIA In the event of a hardware failure during a test run, testing will be stopped immediately. If the failure is directly related to the structural integrity of the test article itself, or it affects the qualification test objectives, the testing will not continue and the customer will be notified immediately. If the failure occurs in test fixturing hardware or equipment, the Code 740 test engineer will make the decision whether or not to continue testing. If testing continues after such a failure, it will be fully documented in the test report and the customer will be notified as soon as possible. In addition, anyone witnessing a situation that could prove to be unsafe to the personnel or hardware may call a halt to the testing. A failure is considered to have occurred and testing shall be interrupted for any of the following reasons: 1. Damage to the test article. This will be based upon visual inspection. A shift in natural frequencies between the pre and post sine sweep test signatures of more than 5% will require evaluation. 2. Operation of the facility or support equipment such that the test article is endangered. 3. Input testing levels are not in accordance with specifications. 5

CHAPTER 5 RANDOM VIBRATION TESTS ON DIP-PCB ASSEMBLY

117 CHAPTER 5 RANDOM VIBRATION TESTS ON DIP-PCB ASSEMBLY 5.1 INTRODUCTION Random vibration tests are usually specified as acceptance, screening and qualification tests by commercial, industrial, and military