Document # Date Effective

INFN-XXX-01 Jan 04 2008

Author: Supersedes

Alessandro Brez

Massimo Minuti

Michele Pinchera

None

Subsystem/Office

Document Title

INFN-XXX-01 XPOL Environmental Test Report

INFN-XXX-01 XPOL Environmental Test

Report

ISSUED BY: A. Brez, M. Minuti, M. Pinchera _______________________

CHECKED BY: A. Brez _______________________

APPROVED BY: R. Bellazzini _______________________

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Change History Log

Revision Effective Date Description of Changes

01 Jan 04, 2008 Initial Release

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Table of contents

INFN-XXX-01 XPOL Environmental Test Report ..........................................................................1

Change History Log ..........................................................................................................................2

Table of contents ...............................................................................................................................3

1. Purpose.....................................................................................................................................4

2. Acronyms and Definitions .......................................................................................................4

3. Applicable Documents.............................................................................................................4

4. General Information.................................................................................................................5

5. CU POST-SHIP RECEIVING INSPECTION AND TESTS Error! Bookmark not defined.

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1. Purpose

The present document reports the results of the XPOL prototype environmental test.

2. Acronyms and Definitions

CG – Center of Gravity

TBD – To Be Determined

DOF – Degree Of Freedom

3. Applicable Documents

Documents relevant to the development of this procedure include:

[1] NASA-GSFC-STD-7000 General Environmental Verification Standard (Gevs)

[2] NASA-MSFC-HDBK-670 General Environmental Testing Guidelines

[3] ORBITAL Pegasus® User’s Guide June 2007, Release 6.0

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4. General Information

Start of the Test: December 21th, 2007

End of the Test: January 04th, 2008

Facility: INFN (Pisa, Italy)

Test Shaker : TYRA-TV5220

Shaker controller: DATA PHYSICS – Signal Star Vector

Accelerometer: PCB Piezotronics – 352A24 ICP accelerometer

5. XPOL CAD/FEM models and analyses

Preliminary structural and modal FEM analyses have been performed to design the XPOL board

interface frame and the vibration vertical fixture (the plate fixture was supplied with the test

equipment).

CAD software: UGS I-Deas NX12

FEM software: ANSYS V11

The results, see below, show that neither the equipment nor the board with the interface frame have

frequency modes below 2000Hz. This results have been confirmed by the vibration tests.

NOTE:

The Beryllium window of this XPOL prototype is 50µm thick. During the Thermal vacuum test the

window load = 1bar. The design/analysis factors of safety for the Beryllium must be 1.4 yield and

1.6 ultimate (as per NASA-GSFC-STD-7000). These factors are not satisfied by a conservative

FEM analysis, however the window has been already verified with a leak test (load=1bar)

performed prior the prototype delivery by the manufacturer.

The space version of XPOL will have a Beryllium window 200µm thick and the conservative FEM

analysis resulting factors of safety (1.6 yield and 2.5 ultimate) satisfy the above requirements (see

Fig. 1).

Fig. 1 XPOL Beryllium window 200µm thick FEM analysis

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5.1. XPOL Board And Interface Frame Analysis

The interface frame has been designed to simulate the structural/thermal interface frame that will be

part of the space version of XPOL

Fig. 2 XPOL Board and Interface Frame Assembly

Fig. 3 XPOL Board and Interface Frame Assembly - Modal Analysis, 1st Mode

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Mesh data:

Nodes=17557

Tetrahedral Elements=6738

Modal analys results:

Modes Frequence [Hz]

1. 2838.7

2. 3268.2

3. 3817.6

4. 3899.

5. 4090.4

6. 4296.5

5.2. XPOL Vertical Fixture Analysis

Fig. 4 XPOL Vertical Fixture - Modal Analysis, 1st Mode

Mesh data:

Nodes=22350

Tetrahedral Elements=10776

Modal analys results: Modi Frequenza [Hz]

1. 2028.7

2. 2831.

3. 3055.6

4. 4500.5

5. 6606.1

6. 7387.6

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5.3. XPOL Board and Vertical Fixture Analysis

Fig. 5 Vibration Test XPOL Board and Fixture Assembly 3D model

Fig. 6 XPOL Board bolted to the Vertical Fixture - Modal Analysis, 1st Mode

Mesh data:

Nodes=43700

Tetrahedral Elements=17658

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Modal analys results: Modi Frequenza [Hz]

1. 2336,5

2. 2971,3

3. 3078,4

4. 3159,7

5. 3305

6. 3793

6. Experimental setup and results.

In Fig. 7 the three axes setups are shown. For each axis we have performed a sine sweep between

20 and 2000Hz at 2oct/min and a random test 3dB for 75s over the predicted random vibration

environment of the Pegasus rocket. In all the random tests the item was vibrated to an overall 3grms

In Fig. 8 are shown the sine sweep and the random test results. As foreseen by the FEM no

resonances are present in the 20-2000Hz range. The detector was tested with a Fe55

source at the

usual voltages after the random test showing the same stable performance as before the vibe test

Fig. 7 Vibe test experimental setup. a) X axis b) Y axis c) Z axis

a b

c

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Fig. 8 The sine sweep spectra and the random tests results for the three axes. As foreseen by he FEM no

resonances are present in the 20-2000Hz range