SIST-TP CEN/TR 17603-32-25:2022

Space engineering - Mechanical shock design and verification handbook

The intended users of the “Mechanical shock design and verification handbook” are engineers involved in design, analysis and verification in relation to shock environment in spacecraft. The current know-how relevant to mechanical shock design and verification is documented in this handbook in order to make this expertise available to all European spacecraft and payload developers.
The handbook provides adequate guidelines for shock design and verification; therefore it includes advisory information, recommendations and good practices, rather than requirements.
The handbook covers the shock in its globally, from the derivation of shock input to equipment and sub-systems inside a satellite structure, until its verification to ensure a successful qualification, and including its consequences on equipment and sub-systems. However the following aspects are not treated herein:
- No internal launcher shock is treated in the frame of this handbook even if some aspects are common to those presented hereafter. They are just considered as a shock source (after propagation in the launcher structure) at launcher/spacecraft interface.
- Shocks due to fall of structure or equipment are not taken into account as they are not in the frame of normal development of a spacecraft.

Raumfahrttechnik - Handbuch zu mechanischem Design und Verifikation für Stöße

Ingénierie spatiale - Chocs mécaniques: Manuel de conception et de vérification

Vesoljska tehnika - Priročnik za načrtovanje in preverjanje mehanskih udarcev

Predvideni uporabniki »Priročnika za načrtovanje in preverjanje mehanskih udarcev« so inženirji, ki se ukvarjajo s projektiranjem, analiziranjem ali preverjanjem v zvezi z udarci v okolju uporabe vesoljskih plovil. Ta priročnik dokumentira dosedanje strokovno znanje v zvezi z načrtovanjem in preverjanjem mehanskih udarcev, da se dostop do njega omogoči vsem evropskim razvijalcem vesoljskih plovil in nosilnih raket.
Priročnik zagotavlja ustrezne smernice za načrtovanje in preverjanje mehanskih udarcev; kot tak vsebuje informacije svetovalne narave, priporočila ter dobre prakse in ne podaja zahtev.
Priročnik obravnava celoten potek udarca, od vira udarca v opremo in podsisteme znotraj satelitske strukture do njegovega preverjanja, da se zagotovi uspešna kvalifikacija, vključuje pa tudi posledice udarca na opremo in podsisteme. Ne obravnava pa naslednjih vidikov:
– v okviru tega priročnika niso obravnavani udarci v notranjosti lansirnika, čeprav so nekateri vidiki skupni tistim, ki so predstavljeni v nadaljevanju. Obravnavani so le kot vir udarcev (po širjenju skozi konstrukcijo lansirnika) na vmesniku med lansirnikom in vesoljskim plovilom;
– udarci zaradi padca konstrukcije ali opreme niso upoštevani, saj ne sodijo v okvir običajnega razvoja vesoljskega plovila.

General Information

• Status: Published
• Publication Date: 29-Jun-2022
• ICS: 49.140 - Space systems and operations
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 20-Jun-2022
• Due Date: 25-Aug-2022
• Completion Date: 30-Jun-2022
• Ref Project: CEN/TR 17603-32-25:2022 - Space engineering - Mechanical shock design and verification handbook

Standards Content (Sample)

SLOVENSKI STANDARD
SIST-TP CEN/TR 17603-32-25:2022
01-september-2022
Vesoljska tehnika - Priročnik za načrtovanje in preverjanje mehanskih udarcev
Space engineering - Mechanical shock design and verification handbook
Raumfahrttechnik - Handbuch zu mechanischem Design und Verifikation für Stöße
Ingénierie spatiale - Chocs mécaniques: Manuel de conception et de vérification
Ta slovenski standard je istoveten z: CEN/TR 17603-32-25:2022
ICS:
49.140 Vesoljski sistemi in operacije Space systems and
operations
SIST-TP CEN/TR 17603-32-25:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST-TP CEN/TR 17603-32-25:2022

---------------------- Page: 2 ----------------------
SIST-TP CEN/TR 17603-32-25:2022


TECHNICAL REPORT CEN/TR 17603-32-25

RAPPORT TECHNIQUE

TECHNISCHER BERICHT
June 2022
ICS 49.035; 49.140

English version

Space engineering - Mechanical shock design and
verification handbook
Ingénierie spatiale - Chocs mécaniques: Manuel de Raumfahrttechnik - Handbuch zu mechanischem
conception et de vérification Design und Verifikation für Stöße


This Technical Report was approved by CEN on 13 April 2022. It has been drawn up by the Technical Committee CEN/CLC/JTC 5.

CEN and CENELEC members are the national standards bodies and national electrotechnical committees of Austria, Belgium,
Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia,
Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
























CEN-CENELEC Management Centre:
Rue de la Science 23, B-1040 Brussels
© 2022 CEN/CENELEC All rights of exploitation in any form and by any means Ref. No. CEN/TR 17603-32-25:2022 E
reserved worldwide for CEN national Members and for
CENELEC Members.

---------------------- Page: 3 ----------------------
SIST-TP CEN/TR 17603-32-25:2022
CEN/TR 17603-32-25:2022 (E)
Table of contents
European Foreword . 9
Introduction . 10
1 Scope . 11
2 References. 12
2.1 References of Part 1 . 12
2.2 References of Part 2 . 12
2.3 References of Part 3 . 14
2.4 References of Part 4 . 16
3 Terms, definitions and abbreviated terms . 19
3.1 Terms and definitions from other documents . 19
3.2 Terms and definitions specific to the present document . 19
3.3 Abbreviated terms. 20
4 Background – Shock environment description . 24
4.1 Shock definition and main characteristics . 24
4.1.1 Shock definition . 24
4.1.2 Physical aspects of shocks . 25
4.1.3 Main shock effects . 25
4.1.4 Shock response spectra (SRS) . 26
5 Shock events . 31
5.1 Shock occurrence . 31
5.2 Shock environmental categories . 31
6 Introduction to shock design and verification process . 34
6.1 Presentation of the global process . 34
6.2 Means to conduct an evaluation of shock environment and criticality. 36
7 Shocks in spacecraft . 38
7.1 Overview . 38
7.2 Potential shock sources for spacecraft . 38
7.3 Shocks devices description . 39
2

---------------------- Page: 4 ----------------------
SIST-TP CEN/TR 17603-32-25:2022
CEN/TR 17603-32-25:2022 (E)
7.4 Detailed information on specific shock events . 42
7.4.1 Overview . 42
7.4.2 Launcher induced shocks. 42
7.4.3 Clampband release . 49
7.4.4 Other S/C separation systems. 56
7.4.5 Internal shock sources . 64
7.4.6 Landing and splashdown. 69
7.5 Conclusion . 72
8 Shock inputs derivation by similarity-heritage-extrapolation . 73
8.1 Overview . 73
8.2 Similarity-heritage-extrapolation methods principle . 74
8.2.1 Overview . 74
8.2.2 Use of database . 74
8.2.3 Zoning procedure . 78
8.2.4 SRS ratio as approximation of transfer functions . 79
8.2.5 Difference between structural model and flight model . 82
8.2.6 Statistical methods to derive maximum expected environment. 83
8.3 Similarity-heritage-extrapolation methods in practice . 92
8.3.1 Method A – Point source excitation . 93
8.3.2 Method B – Clampband excitation . 99
8.3.3 Method C – Launcher induced shock . 105
8.3.4 Method D – Unified approach and practical implementation of
attenuation rules for typical spacecraft shock generated environments . 114
8.3.5 Additional attenuation factors . 121
8.3.6 Method E – Shock responses in instruments. 122
9 Shock inputs derivation by numerical analysis . 126
9.1 Numerical simulation principles . 126
9.1.1 Rationale and limitations . 126
9.2 Finite Element Analysis (FEA) Numerical methods . 127
9.2.1 Comparison of explicit and implicit methods . 127
9.2.2 Explicit and implicit integration schemes . 129
9.2.3 Example of simulation codes (implicit and explicit) . 129
9.2.4 Modelling aspects . 131
9.3 Statistical Energy Analysis (SEA) Numerical Methods . 152
9.3.1 The classical SEA approach . 152
9.3.2 The Transient SEA formulation . 153
9.3.3 Prediction of shock response by Local Modal Phase Reconstruction
(LMPR) . 153
3

---------------------- Page: 5 ----------------------
SIST-TP CEN/TR 17603-32-25:2022
CEN/TR 17603-32-25:2022 (E)
9.3.4 Virtual SEA modelling for robust SEA modelling in the mid-frequency. 155
9.4 Best practices for shock derivation by simulation . 157
9.5 Examples of methodology for numerical simulation . 158
9.5.1 Numerical simulation for clampband release . 158
9.5.2 Numerical simulation for Shogun . 161
9.5.3 Numerical simulation for launcher induced shock . 165
9.5.4 Implicit vs. explicit method: Example of a shock prediction on a
complex structure . 174
9.5.5 Shock prediction analysis examples using SEA-Shock module of
SEA+ software . 176
10 Deriving a specification from a shock environment . 180
10.1 Specification tool . 180
10.2 Deriving the qualification environment – MEE and qualification margin . 183
10.3 From level derivation/Measure to specification . 183
11 Shock attenuation . 185
11.1 Definitions . 185
11.1.1 History of shock attenuation . 185
11.1.2 Impedance breakdown . 186
11.1.3 Shock and vibration Isolator . 187
11.1.4 Damper . 189
11.1.5 Shock absorber . 190
11.2 Theoretical background . 191
11.2.1 Shock attenuation problematic approach . 191
11.2.2 Shock isolator device features . 193
11.2.3 Rubber and damping effect . 193
11.2.4 Elastomer type selection . 199
11.3 Attenuator device development. 202
11.3.1 Overview . 202
11.3.2 Attenuator requirement definition . 202
11.3.3 Attenuator device development logic . 205
11.4 Attenuator device manufacturing . 210
11.4.1 Overview . 210
11.4.2 Manufacturing process . 210
11.4.3 Moulding technology . 211
11.4.4 Manufacturing limitations. 213
11.5 Product assurance logic. 213
11.6 Existing attenuator products . 214
11.6.1 Overview . 214
4

---------------------- Page: 6 ----------------------
SIST-TP CEN/TR 17603-32-25:2022
CEN/TR 17603-32-25:2022 (E)
11.6.2 Compact shock attenuators for electronic equipment . 214
11.6.3 SASSA (shock attenuator system for spacecraft and adaptor) . 216
11.6.4 Shock isolators for EXPERT on-board equipment . 221
12 General approach to shock verification . 226
12.1 Rationale for shock verification . 226
12.2 Test rationale and model philosophy . 229
12.2.1 Qualification test . 229
12.2.2 Acceptance test . 231
12.2.3 System / subsystem distinction . 231
12.2.4 Model philosophy . 231
12.3 Environmental test categories . 233
12.3.1 Combination or separation of sources . 233
12.3.2 Pyroshock environmental categories . 233
12.4 Shock sensitive equipment and severity criteria . 235
12.4.1 Identification of shock sensitive equipment . 235
12.4.2 Severity criteria . 235
12.4.3 Synthesis . 247
12.5 Equivalence between shock and other mechanical environment . 248
12.5.1 Quasi static equivalence – effective mass method . 248
12.5.2 Use of sine vibration test data . 251
12.5.3 Use of random vibration test data . 252
12.6 Similarity between equipment – Verification by similarity . 257
12.6.1 Introduction . 257
12.6.2 Similarity criteria for shock . 257
12.6.3 Example of process for verification by similarity . 259
12.7 Specific guidelines for shock verification . 263
12.7.1 Optical instrument . 263
12.7.2 Propulsion sub system . 270
13 Shock testing . 283
13.1 Shock test specifications. 283
13.1.1 Test levels and forcing function . 283
13.1.2 Number of applications . 283
13.1.3 Mounting conditions . 284
13.1.4 Test article operation . 284
13.1.5 Safety and cleanliness . 285
13.1.6 Instrumentation . 285
13.1.7 Test tolerances . 285
5

---------------------- Page: 7 ----------------------
SIST-TP CEN/TR 17603-32-25:2022
CEN/TR 17603-32-25:2022 (E)
13.1.8 Test success criteria . 286
13.2 Criteria for test facility selection . 287
13.3 Test methods and facilities . 288
13.3.1 Basis . 288
13.3.2 Procedure I – System level shock test . 288
13.3.3 Procedure II – Equipment shock test by pyrotechnic device (explosive
detonation) . 302
13.3.4 Procedure III – Equipment shock test by mechanical impact (metal-
metal impact) . 308
13.3.5 Procedure IV – Equipment shock test with an electrodynamic shaker . 320
13.4 Test monitoring . 336
13.4.1 Accelerometers . 336
13.4.2 Strain gauges . 351
13.4.3 Load cells . 356
13.4.4 Laser vibrometer . 359
13.4.5 Acquisition systems . 366
13.5 In-flight shock monitoring . 380
13.5.1 Overview . 380
13.5.2 VEGA in-flight acquisition systems . 380
14 Data analysis tools for shock . 383
14.1 Introduction . 383
14.2 Shock Response Spectra (SRS) . 383
14.2.1 Basis . 383
14.2.2 Definition . 383
14.2.3 SRS properties . 385
14.2.4 SRS algorithm . 388
14.2.5 Recommendations on SRS computation . 389
14.2.6 Q-factor . 390
14.2.7 SRS limitations . 392
14.3 Fast Fourier Transform (FFT) . 393
14.3.1 FFT definition . 393
14.3.2 Precautions . 393
14.4 Time-Frequency Analysis (TFA) . 393
14.4.1 General . 393
14.4.2 Linear Time-Frequency Transform (TFT) . 394
14.4.3 Quadratic Time-Frequency Transform. 397
14.4.4 Interpretation and precautions . 401
14.5 Prony decomposition . 401
6

---------------------- Page: 8 ----------------------
SIST-TP CEN/TR 17603-32-25:2022
CEN/TR 17603-32-25:2022 (E)
14.5.1 Definition . 401
14.5.2 Basic scheme . 401
14.5.3 Advanced scheme. 403
14.5.4 Use and limitation . 404
14.6 Digital filters . 406
14.6.1 Basis . 406
14.6.2 Definition and parameters . 406
14.6.3 FIR filters . 407
14.6.4 IIR filters . 408
14.6.5 Precautions . 409
15 Shock data validation . 410
15.1 Overview . 410
15.2 Visual inspection . 410
15.3 Data analysis – simplified criteria . 413
15.3.1 Duration analysis . 413
15.3.2 Validity frequency range . 413
15.3.3 Final validity criteria - Positive versus negative SRS . 415
15.4 Data analysis – refined criteria – Velocity validation . 415
15.5 Corrections for anomalies . 416
15.5.1 Overview . 416
15.5.2 Correction for zeroshift . 416
15.5.3 Correction for power line pickup . 420
16 Introduction to shock damage risk assessment and objective . 424
16.1 Overview . 424
16.2 Assessment context . 424
16.3 Outputs of SDRA and associated limitations . 425
17 Unit susceptibility with respect to shock. 426
17.1 Overview . 426
17.2 Derivation of qualification shock levels at unit interface . 428
17.3 Identification of critical frequency ranges . 428
17.4 Considerations related to life duration and mission . 431
17.5 List of shock sensitive components/units . 431
17.5.1 Overview . 431
17.5.2 Electronic components and associated degradation modes . 432
17.5.3 Functional mechanical assemblies . 456
17.5.4 Mechanisms and associated degradation modes . 459
7

---------------------- Page: 9 ----------------------
SIST-TP CEN/TR 17603-32-25:2022
CEN/TR 17603-32-25:2022 (E)
18 Shock damage risk analysis . 460
18.1 Required inputs for detailed SDRA . 460
18.2 Evaluation of transmissibility between equipment and sensitive components
interfaces . 461
18.2.1 Overview . 461
18.2.2 Derivation by extrapolation from test data . 461
18.2.3 Shock response prediction based on transmissibility . 465
18.2.4 Guideline for equipment shock analysis . 466
18.3 Verification method per type of components and/or units . 480
18.3.1 Electronic equipment . 480
18.3.2 Mechanisms – Ball bearings . 502
18.3.3 Valves . 526
18.3.4 Optical components . 533


8

---------------------- Page: 10 ----------------------
SIST-TP CEN/TR 17603-32-25:2022
CEN/TR 17603-32-25:2022 (E)
European Foreword
This document (CEN/TR 17603-32-25:2022) has been prepared by Technical Committee
CEN/CLC/JTC 5 “Space”, the secretariat of which is held by DIN.
It is highlighted that this technical report does not contain any requirement but only collection of data
or descriptions and guidelines about how to organize and perform the work in support of EN 16603-
32.
This Technical report (CEN/TR 17603-32-25:2022) originates from ECSS-E-HB-32-25A.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such
patent rights.
This document has been prepared under a mandate given to CEN by the European Commission and
the European Free Trade Association.
This document has been developed to cover specifically space systems and has therefore precedence
over any TR covering the same scope but with a wider domain of applicability (e.g.: aerospace).
9

---------------------- Page: 11 ----------------------
SIST-TP CEN/TR 17603-32-25:2022
CEN/TR 17603-32-25:2022 (E)
Introduction
In recent years, discussions concerning “what to do about shock” in relation to spacecraft have taken
more importance. During launch and deployment operations, a spacecraft can be exposed to energetic
shock environments. As spacecraft have become more capable, more equipment can be flown, and
components are closer together. In addition, more sophisticated and delicate instruments are flown to
maximize mission results.
As such, the shock environment has become a sou
...