WG ESS report 45 brussels - CEEES · HOLY Michel retired/SSEE ... corresponding source, to Marco ,...

15 september 2005 page 1/31

45th CEEES Meeting

Minutes of R and ESS WG

Meeting location : Hotel SCANHOTEL Brussel

Date : 16th February 2006

Attendees : see list hereafter


Name

1st

name

Company/Society phone

fax email

AXEBSSON Bengt AXEB AB [email protected]

RUDING Gunnar Ass. of Swedish Engineering

Industries /SEES

46 8 653 0418 46 8 653 0419 [email protected]

GRZESKOWIAK

Henri MBDA F /ASTE +33 1 34 88 35 23 +33 1 34 88 34 75

[email protected] office

[email protected] home

HOLY

Michel retired/SSEE +41 1 865 46 68 [email protected]

PALMEN Helge VTT Industrial Systems /SEEF +358 9 456 56 31 +358 9 456 7042

[email protected]

PEREGO Marco Angelantoni Industrie SPA +39 075 8955 213 +39 075 8955 200 [email protected]

WEETCH Colin e2v Technologies/SEE + 44 1245 453654 [email protected]


1 - ADOPTION OF THE 44rd

CONGRESS R&ESS MEETING MINUTES

The minutes are adopted.

2 - Apologies FOR ABSENCES

No.

3 - INTRODUCTION OF NEW MEMBERS

No new member.

5- ESS ACTIVITY

It was agreed that there is a need for a basic terminology of terms relative to the tests , environmental

engineering and reliability such as MTBF, MTTR, reliability test, accelerated test ….

It was proposed that all the members send a list of these terms , with the known definitions and

corresponding source, to Marco , that will arrange a digest of all these inputs for next meeting.

Michel has proposed a list ( see in attachment 1). This list has been examined during the meeting.

Durability : HG will provide next time the definition (adopt the definition of the IEC56) ; as it is related

to the cost, is it affiliated to the life cycle cost ? Refer to the IEC 56.

Michel Holy wonders if there is a Mathematical relation between Reliability and Maintnability ?

Helge will examine the compatibility between the proposed terminology and IEC one.

HG will provide return from reliability and statistician collegues on mathematical description.

Michel Holy will provide quick definitions of abbreviations. He is requesting to verify that the structure

of the terms is complying with the content of the definition of the related terms.

6- R ACTIVITY

7-

6.1 Life cycles environmental profile

It has been also decided in London to work of the product life cycles .

Extract from London meeting report : “

• The expected life profile of a product in different sectors of activity *, which is an important

issue to consider in product sustainability growth

o Output : life cycle environmental profile characterisation : climatic related parameters

such as number of cycles, temperature range , rate of change , humidity, pressure if

relevant, chemical contaminents , etc.)

or mechanical related parameters such as PSD for vibration, SRS or time histories for

shock, etc.

• Operational use :

o Dormant periods ( storage)

o Functional activation( ON/OF, junction temperature elevation, electrolytic

phenomenon,etc.)

• Identify the expected processes or modes of failure

• Assess the life duration of different type of technologies

*The sectors of acitivity covered by the current members are : mobile phones, telecommunication,

automation/robotics, nuclear power plant, control of climatic chambers, electronics in automotive

industry, missiles.”

Henri is proposing as a beginning to consider the following documents in which there are elements on life

cycle profile description:


- French CIN EG 1 “ Taking into account the Environment through a

product development ( see an English version as attached document)

- An example of life cycle description ( see a french version as attached

document )

- Hank Caruso fundamental paper on LCEP , presented at IEST ( distributed during the current

meeting) .

- Henri has evocated the Strength / Stress approach ; the general appendix of GAM EG 13 is

describing this approach in one appendix ( see annex 14 of General Appendix of GAM EG 13 in

French , attached to the meeting report , in French)

Henri has also introduced a document dedicated to program management structuration : EN 9200 .

The work will be continued on the example of life cycle description on the mobile equipment dedicated to

pollution measurement.

6.2 Different types of tests

6.2.1 List of withhold tests

Type of test In charge of

feasability , design aid Colin Done : see att.2

Development test Michel Done : see att 5

Reliability growth test (RGT) Colin

Higly accelerated tests Henri Done : see att.3

Accelerated tests Helge Under progress : see att 4

Qualification Aad *

Reliability demonstration Colin

ESS including HASS Henri

Acceptance test Bengt *

Production reliability acceptance test (PRAT) To be

determined

Pre production (zero production) Gunnar

Life duration Colin

Verification (validation) Bengt *

* to be confirmed

6.2.2 Template to apply to each of these tests

1 Test objective (purpose,definition…)

2 What is driving you for performing the test ?

3 Level of assembly of the product submitted to test

4 Number of items submitted to test

5 Type of product relevant to be submitted to the test ( mass volume low price product ,..)

6 Test duration (days, weeks, months..)

7 Separate or combined environments

8 Product strength and environment stress variabilities are or aren’t considered

( in the process of deriving the test severity)

9 Does the test bring knowledge on reliability parameters ?

10 Does the test consume totally or partially the life potential ot the equipment submitted to test ?

11 main norms , standards, technical references relative to this type of tests

For next meeting : the proposed persons will try to apply the template to the corresponding test .


Accelerated tests by Helge Palmen ( see attachment 4) Accelerated stress (Objective : identify product weaknesses by stimulation ) and accelerated life testing

(simulation of the field stresses) : the discussion arose again in order to clarify the differences between

the 2 types of tests.

The proposal of Helge is very close the above one presented within the START document established by

the RAC , organisation depending upon US DOD Air force Command.

The WG is not willing to adopt AST as part of the family of accelerated testing tests ; ALT is the

normally widely accepted accelerated testing approach ; AST is oriented precipitation latent defects (

purpose of ESS ) or design weaknesses (purpose of highly accelerated tests) : even still based on a “

workable” knowledge of the failure mechanism as RAC proposes , AST has to do either with ESS ( not a

test), or with higly accelerated tests ( not basically requesting knowledge of the physicall madel of failure)

, and not with accelerated testing. Otherwise, it would be confusing .

The lecture of the article of ISTIA sent to WG members has clarified the 3 types of accelerated tests :

- those based on acceleration by reducing the number of experiments , based on design of experiments

- the acceleration based on statistical models ,

- the acceleration by usage of physical models of failure.

Development tests by Michel Holy (see attachment 5)

Has been examined : see attachment 4

6.3 CEN WG10/EG8

Next meeting :

the § “ review and comparison of environmental management standards” page 39 and

following will be discussed

recommendation for a future work : page 29 ( to confirm)

first part of DEF STAN 0035 and CIN EG 1 ( in English) will be discussed


7- MISCELLANEOUS

Colin : has evocated last time the risk of hazardus substances ( ROHS) and the impact on the

electrnic reliability. Colin will extract articles from the site of NPL and INTEL that address the

concern of ROHS impact on product reliability and will be examined next meeting.

Marco Perego indicates that Far East countries don’t know the directive. Colin precises that

even the European companies that made an effort will not be ready for the deadline of

application : sept 2006. The Japanese have emitted the same kind of directive several years

ago.

8 TOUR OF TABLE

- Colin

o Good recruitment within SEE : 43 retiring and 27 arriving , that is considered as

encouraging

o 4 courses are organized per year : climatic, vibration,ESS and signal/modal

analysis

- Gunnar :

o interest in Environmental Engineering in the offshore and nuclear power plant

industries , with corrosion concerns : the use of non metallic materials on the

platforms is very high

o difficulty of people to participate to working groups ; the new themes are

gathering some people , the ordinary is going down ; new methods of

communication have to be found

o 30 students have been trained this year to the containt of the book on

Environmental Engineering

- Helge : Kotel has started 2 projects; prototype and industrialisation with :

o Environmental legislation

o Mechanical design

o Virtual prototyping

- Michel : a workshop is to be organised on the specification of a product LCEP ( life cycle

environmental profile)

- Marco :

o A basic course on Environmental Engineering was organized in Jan 2006

o February 2006 : course on accelerated testing with the support of University of

Perrugia

o March 2006 with ERI ( Tustin) : course on vibration and reliability

o April 2006 : advanced course on Environmental Testing

- Henri

The ASTE guide on ESS based on highly accelerated tests is finished ; see

summary in appendice 7.


List of virtual members

Current members + following list.

TOOLA Arja NOKIA +358 40 7685072 [email protected]

BODIN Hakan LabTest ? [email protected] ?

STREUBEL Reinhard BGT 49 7551896276 49 7551 892163 [email protected]

TURTOLA Antti KOTEL 358994565639 [email protected]

VAN DORP

Aad National Aerospace

Laboratory

+31-527-248457 +31-527-248210

[email protected]

TURTOLA Antti KOTEL 358994565639 35894567042 [email protected]


Definition(s) of Terms Dedicated to Availability, Reliability & Maintainability

1) Terminology-Structure

Environment Stress has direct influences on "Reliability" and "Maintainability"

2) Terms of Reliability and their abbreviations

- Reliability Function R(t)

- Failure Rate λ(t) - Mean Time Between Failures MTBF - Mean Time To Failures MTTF - Mean Time To Mission - Failures MTTFM - Lifetime TL - Life Cycle LC - Mission Profile MP - Life Environmental Cycle Profile LCEP


Durability: capacity of a functional unity to execute a function required in definite conditions of use and

of maintenance till his(its,her) end of useful life or until what it does not agree any more for economical

or technological reasons (ref: Reliability, Maintenabilité and Availability - October, 1993).

- Dependability: together capacities of a product allowing it to arrange functional specified

performances, at the deliberate moment, during duration foreseen, without damage for itself and for its

environment (ref: BNAE RG Aéro 00040).

2.1) Relations between the terms of Reliability

∞

MTTF = ∫R(t)•dt (for Lifetime = ∞)

0

for a finite Lifetime the upper limit of the integral is TL

λ(t) = d R(t) / R(t) •dt

This equation shows that the reliability function R(t) is completely defined by the failurerate λ(t) .

With R(0) = 1, the reliability function reads as follows:

t

- ∫ λ(x) dx

R(t) = e 0

For λ(t) = λ = constant it follows:

∞

R(t) = e- λt

and in this case is MTTF = ∫e- λ(t) dt =1/λ

0

2.2) Terms related to Reliability

Reliability - Analysis - Blockdiagramm - Requirements - Verification - Program - Improvement - Assurance of - Evaluation - Of mechanical Items


Failure - Failure Analysis - FMEA (Failure Mode And Effects Analysis)

- FMECA (Failure Mode, Effects and Criticality Analysis) - Failure Cause - Failure Mode - Failure Symptom - Failure Criticality - Failure Effect - Failure Detection - Failure Localisation - 8D process

Fault - Specification-fault - Engineering-fault - Manufacturing-fault - Using-fault

Reliability Improvement during

Engineering - R-Verification - R-Analysis - R-Test

- HASS (Highly Accelerated Stress Screening) - HALT (Highly Accelerated Life Testing)

- R-Demonstration

Manufacturing - ESS

- Qualifications-Tests

Product Use - Reliability Growth

3) Terms of Maintainability and their abbreviations

Is there any mathematical presentation of the following terms ?

- Maintenance

- Preventive Maintenance

- Mean Time To Preventive Maintenance MTTPM : no mathematical presentation (i.e. :

valeur moyenne observée)

- Time Between Preventive Maintenance TBPM : no mathematical presentation (i.e. : valeur

moyenne observée)

- Maintenability : Capacity of a product to be put back(handed) in a state of given functioning, in a

specified limit of time (t), when the work is made according to prescribed procedures and given

conditions. This capacity can be translated in the term of probability M (t).


- Corrective Maintenance

- Mean Time To Repair : MTTR

- Repair Rate µ(t) : Conditional probability that the repairation of a failing product is realized on

an unit of time given from moment t, knowing that it was still not it to t.

3.1) Relations between the terms of Maintainability

to be defined

- µ(t) = d M(t) / M(t) dt (M(t) = maintenability)

- MTTR = = ∫M(t)dt

3.2) Terms related to Maintainability

- Maintainability - Analysis

- Requirements - Verification - Program - Improvement - Assurance of - Evaluation

4) Definitions for Systems and/or Hardware

Functionality

[2] The capability of a product to provide the required function when it is used under specified

conditions.

Operational Availability; Point Availability

[1] Probability that a product will perform its required function under given conditions at a stated

instant of time.

Safety

[1] Ability of a product to cause neither injury to persons, nor significant material damage or other

unacceptable consequences

Remark:

Safety is subdivided into accident prevention (the product is safe working while it is operating

correctly) and technical safety ( the product has to remain safe even if a failure occurs)


[3] State in which the risk of harm (to persons) or damage is limited to an

acceptable level

Note 1: Safety is one of the aspects of Quality

Note 2: The above definition is valid for the purposes of quality standards. the term "safety" is

defined differently in ISO/IEC Guide 2

Usability

[2] The capability of a product to be understood, learned, used and efficient for the user, when used

under specified conditions.

Operational Effectiveness

Logistical Support

[1] All activities undertaken to provide effective and economical use of an product during ist

operating phase.

Maintainability

[1] Probability that preventive maintenance or repair of an item will be performed within a stated

time interval for given procedures and resources.

Remark:

A qualitative definition is:

Ability of a product to be retained in or restored to the ability to perform its required function in a

given time interval under stated procedures and resources.

Maintainability is subdivided in serviceability (preventive maintenance) and reparability (corrective

maintenance or repair)

Useful Life

[1] Total operating time of a product, ending for a nonrepairable product when the failure probability

becomes too high or the product functionality is obsolete, and for a repairable product when the

intensity of failures becomes unacceptable or when after a failure the product is considered to

be no longer repairable.

Remark:

The term "Life Time" is only used for nonrepairable products. It is the time span between initial

operation and failure of a nonrepairable item.


Reliability

[1] Probability that a product will perform is required function under given conditions for a stated

time interval.

Remark:

This does not mean that redundant parts may not fail. Such parts can fail and be repaired.

Defect (only used for software)

[1] Nonfulfillment of an intended usage requirement or reasonable expectation, essentially present

at t=0

Remark:

From a technical point of view, a defect is similar to a nonconformity, however not necessarily

from a legal point of view. Defects do not need to influence the item's functionality. They are

caused by flaws (errors, mistakes) during design, production, or installation. Unlike failures,

which always appear in time (generally randomly distributed), defects are present at t=0.

However, some defects can only be detected when the item is operating and are referred to as

"dynamic defects". Similar to defects, with regard to the cause, are systematic failures; they are

not necessarily present at t=0

[3] Nonfulfillment of an intended usage requirement or reasonable expectation, including one

concerned with safety

Note: The expectation must be reasonable under the existing circumstances.

Defect- Immunity) (only used for software)

[2] The capability of the Software product to maintain a level of performance when used under

specified conditions

Note:

Wear or ageing does not occur in software. Limitations in "reliability" are due to faults in

requirements, design, and implementation. "Failures" due to these faults depend on the way the

software product is used and the program options selected rather than on elapsed time.

Supportability, Maintainability ( for software)

[2] The capability of the software product to be modified. Modifications may include corrections,

improvements or adaptation of the software to change in environment, and requirements and

functional specifications.


Security

[2] The capability of the Software product to protect information and data so that unauthorised

person or systems cannot read or modify them and autorised persons or systems are not

denied access to them.

Failure

[1] Termination of the ability of an item to perform a required function under specified conditions.

Dependability

[1] Collective term used to describe the availability performance and its influencing factors, such as

reliability performance, maintainability performance, and logistical support performance

[3] Collective term used to describe the availability performance and its influencing factors, such as

reliability performance, maintainability performance, and logistical support performance

Note 1: Dependability is used only for general descriptions in non-qualitative terms

Note 2: Dependability is one of the time-related aspects of quality

Note 3: the definition of dependability and note 1 given above are taken from IEC 50(191),

which also includes related terms and definitions.

Functionality ( Capability, Technical Performance)

(1) Ability of an item to meet a service demand of stated quantitative characteristics under given

conditions

(2) The capability of a product to provide the required function when it is used under specified

conditions.

Referenced Documents

[1] A. Birolini, Quality and Reliability of Technical Systems

Springer- Verlag

[2] ISO/IEC 9126-1, Software Engineering - Product Quality Part 1

[3] EN ISO 8402 Quality management and quality assurance - Vocabulary


1.0 What is a Feasibility Study?

A feasibility study is designed to provide an overview of the primary issues related to

a technical and business idea. The purpose is to identify any "make or break" issues

that would prevent the test from being successful. In other words, a feasibility study

determines whether the technical issues make sense, as well as the business issues

but I am concerned with technical issues here.

A thorough feasibility analysis provides a lot of information necessary for the

technical plan. For example, a good market analysis is necessary in order to

determine whether the project is feasibility. This information provides the basis for the

market section of the business plan.

Because putting together a technical and business plan is a significant investment of

time and money, you want to make sure that there are no major roadblocks facing

you when the test plan is finalized and you make the investment in time and

equipment. Identifying such roadblocks is the purpose of a feasibility study.

A feasibility study looks at three major areas:

1. Market issues (Not dealt with)

2. Organizational/technical issues

3. Financial issues (Not dealt with)

Again, this is meant to be a "first cut" look at these issues. For example, a feasibility

study should not do in-depth long-term financial projections, but it should do a basic

break-even analysis to see how much revenue would be necessary to meet your

operating expenses.

The purpose of the business plan is to minimize the risk associated with a new

business and maximizes the chances of success through research and maximizes

the chances for success through research and planning.

(cf. University of California)

Technological Issues

The cost and availability of technology may be of critical importance to the feasibility

of a project, or it may not be an issue at all.

For example, a service organization, such as a childcare centre, will have a few

equipment and other technology- related issues to address. A manufacturing


enterprise, on the other hand, may have a number of complex technology questions

to analyze in order to determine whether or not the business is feasible.

Key questions to answer include:

a. What are the technology needs for the proposed business?

b. What other equipment does your proposed business need?

c. Where will you obtain this technology and equipment?

d. When can you get the necessary equipment?

How does your ability to obtain this technology and equipment affect your start-up

timeline?

e. How much will the equipment and technology cost?

Keeping in mind that technology doesn't necessarily mean complex machinery; if

your business simply needs a personal computer, printer, and fax machine, those are

your technological needs.

However, making wise decisions on even simple purchases such as office machines

may require some research. Obviously there are numerous types of personal

computers on the market. You many want to check Consumer Reports for their

recommendations, do some comparative shopping, and ask acquaintances about

their experiences with different companies. Your cost estimates will get plugged into

your financial projections.

Naturally, the more complex the technology you need, the more research that will be

required to make good decisions about it. This is important and should not be looked

at trivially.

Feasible:

“an examination of a situation to decide whether a suggested method, plan or piece

of work is possible or reasonable”.

Feasibility: noun {U}

Whether something is feasible:

"People who consider only price, and not value, are the lawful prey of those who

purvey shoddy goods" John Ruskin (1819 - 1900)

2.0 The Technical Issues to Look at During the Feasibility Study


In the commercial market we have to decide what we trying to achieve

with a certain test. The main thrust is always the reliability of the

product being manufactured.

The product life cycle begins at the component level and continues through assembly

level; the life cycle includes exposure to the following environments

Assembly/process

Testing

Storage

Transportation

Operating

Servicing ( preventive and corrective maintenance)

2.1.1 Assembly/Process

During processing and assembly of electronic assemblies, temperature excursions

take place, e.g. soldering including reflow, cleaning or imposed thermal cycling tests.

These temperature excursions can be damaging to some parts of the assembly and

consume some part of the available life. This damage should be minimized by

keeping the number of excursions to a minimum and the damage needs to be

considered in the overall reliability estimates.

2.1.2 Testing

When devising the overall reliability test plan the frequency of applied test to the

device and the fatigue that the testing induces into the product will be identified.

2.1.3 Storage

Storage tests will be defined by the product specification. The storage life of the

product will be identified which may range from a few months to many years. A

storage life cycle may include storage in a mobile unit to storage in a temperature-

controlled warehouse.

2.1.4 Transportation

Transportation is not a single event that is simply defined. Each vehicle type may

impose unique environmental loads. Each may also provide protection from certain

environmental conditions. Duration and frequency of occurrence will influence how


environmental effects are accumulated over time. The

transportation configuration and degree of loading can also

affect the loads imposed on the product.

2.1.5 Operating

It is assumed that the operational characteristics will not affect the reliability test as

the unit is a low power device and operational tests.

2.1.6 Environmental Stress Screening (ESS)

ESS has the potential to identify latent defects that may cause early failures in a

product. ESS needs to be specifically designed to accelerate the failure of 'weak'

elements in the assembly. ESS does not add to the number of such failures but

causes them to occur in a significantly shorter period of time.

Effective ESS programmes should be supported by well planned `Root Cause

Analysis' (RCA) and corrective action resources. These enable timely corrective

actions, elimination of latent defects and ultimate removal of the ESS process subject

to continued monitoring and control of the manufacturing process.

3.0 Conclusion

All the above tests will be scrutinized during a feasibility study, equipment,

infrastructure human resource and all the associated cost that go with these

requirements.

This is the first part in looking at a reliability test programme.

Colin Weetch

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l th

e e

xis

tence o

f th

e r

ele

vant

cause o

f defe

ct

and p

ow

er

so

to c

orr

ect

it.

- 2

-nd c

ase:

the r

ele

va

nt ca

uses o

f fa

ilin

g

pre

sum

ed c

an a

ffect a p

riori o

nly

a w

eak f

raction o

f

the c

om

ple

te p

op

ula

tion o

f th

e p

roduct (f

or

exam

ple

:

less tha

n 5

% o

f th

e p

op

ula

tion).

In t

hat case,

it is n

ot

very

pro

bab

le t

hat

a lim

ited

num

ber

of

HIG

LY

AC

CE

LE

RA

TE

D T

ES

TS

allo

ws to r

evea

l th

is r

ele

vant

cause. A

s e

xam

ple

, th

e u

se o

f th

e m

odel bin

om

ial

ind

icate

us tha

t if o

ne h

ope

s to r

eveal an r

ele

va

nt

cause o

f fa

iling a

ffecting o

nly

5 %

of

the p

opu

lation

with a

pro

bab

ility

of

the

success o

f 80 %

, it w

ou

ld b

e

necessary

to

subje

ct a

bout

30 c

op

ies to

the

test of

HIG

LY

AC

CE

LE

RA

TE

D T

ES

TS

. S

uch

qu

antity

is

tota

lly incom

patible

with t

he

im

pera

tive

manufa

ctu

rers

. C

onsequen

tly,

the H

IGL

Y

AC

CE

LE

RA

TE

D T

ES

TS

re

aliz

ed in th

e p

hase o

f

conception /

de

ve

lopm

ent on a

n a

lwa

ys v

ery

lim

ited

num

ber

of

copie

s c

an n

ot h

ave

a g

reat eff

icie

ncy

tow

ard

the r

eve

alin

g o

f th

is t

yp

e o

f defe

cts

. O

nly

, h

igly

accele

rate

d E

SS

(H

AS

S)

in the p

hase o

f pro

duction

will

be s

usceptible

to r

eveal, in a

dd

itio

n t

o t

he

manufa

ctu

ring d

efe

cts

, th

ese d

efe

cts

of

the

conception w

hic

h w

ou

ld a

ffect on

ly a

we

ak fra

ction o

f

the p

roducts

during

the

ir p

rofile

of

life.

With r

egard

to

the

obta

inin

g the

lim

its o

f fu

nction

ing

and /

or

of

destr

uction o

f th

e p

rod

uct, th

e m

ajo

r

difficulty p

laces its

elf in th

e s

tatistica

l chara

cte

r

associa

ted

to t

hese s

izes.

So, th

e o

bta

inin

g in a

diffe

rent w

ay g

iven v

alu

e o

n the

lim

it o

f fu

nctionin

g th

e

sin

gle

cop

y d

oes n

ot re

vea

l in

evitab

ly th

e c

entr

al

va

lue o

f th

e s

tatistica

l d

istr

ibution o

f th

is lim

it w

hic

h

could

be a

ssocia

ted to a

n im

port

ant popu

latio

n o

f th

e

teste

d p

roduct. I

n p

art

icu

lar,

this

unit e

xperi

menta

l

15

se

pte

mb

er

20

05

pa

ge

21

/31

5

Typ

e o

f pro

duct re

leva

nt to

be s

ubm

itte

d t

o th

e test (

mass v

olu

me lo

w p

rice p

roduct ,..)

1.

Facto

rs b

ou

nd

in

co

sts

an

d in

th

e s

trate

gic

co

nte

xt

"

Str

ate

gic

aspects

bo

und(c

onnecte

d)

to t

he

mark

et (e

x: an

y ri

gh

t fo

r th

e e

rror

from

the lau

nch o

f

the f

irst copie

s o

n t

he m

ark

et, m

atu

rity

of

the p

roduct

from

the s

tart

ing,

…)

"

The im

pera

tives o

f re

ducin

g the

costs

of

resum

ption o

f th

e d

efe

cts

of

conception

"

The im

pera

tives o

f re

ducin

g the

tim

es o

f

develo

pm

ent

"

The im

pera

tives o

f re

ducin

g the

dura

tio

ns o

f

ES

S

"

Als

o a

pp

lica

ble

in c

ase o

f chang

e o

f

techno

log

ies if

conditio

ns o

f use a

re c

orr

espond

ing to

a lig

ht

en

vir

onm

ent

"

Hig

h m

ass p

roduction w

ith

weak e

nvironm

enta

l

conditio

ns

"

off

the s

helf e

qu

ipm

ent sub

mitte

to lig

ht

environm

ent in

op

era

tion

2.

bo

un

d(c

on

necte

d)

Facto

rs o

n t

he r

etu

rn t

o

exp

eri

en

ce

(R

EX

)

"

The insuff

icie

nt o

pera

tion

al re

liab

ility

of

sim

ilar

pro

ducts

alread

y d

eve

lop

ed a

nd p

roduced b

y t

he

com

pan

y (

RE

X in

op

era

tion

)

"

Num

ero

us p

roble

ms g

enera

ted in p

rod

uctio

n

on s

imila

r pro

ducts

of

the p

revio

us g

enera

tio

n (

RE

X in

pro

duction)

3.

Facto

rs b

ou

nd

to

th

e u

nc

ert

ain

tie

s

"

The u

se o

f te

chno

logie

s in v

ery

in

no

vative

chara

cte

r or

of

the n

ew

str

ate

gie

s o

f im

pla

nting

of

constitu

ents

"

Use o

f ne

w p

rocesses in p

roductio

n

15

se

pte

mb

er

20

05

pa

ge

22

/31

6

Test dura

tion

(da

ys,

we

eks, m

onth

s..)

"

The d

ura

tion o

f a h

igly

accele

rate

d t

ests

cam

paig

n is v

ery

brief

: of

the o

rder

of

5 d

ays o

n

avera

ge

7

Sep

ara

te o

r com

bin

ed e

nvir

onm

ents

C

om

bin

ed e

nvironm

ents

are

not

a c

on

ditio

n b

ut can

be e

mplo

yed if

necessary

to d

isclo

se a

failu

re.

For

exam

ple

, w

e c

an g

rad

ually

incre

ase t

he v

ibra

tion

level fo

r a g

ive

n r

ate

of

tem

pera

ture

variatio

n o

r b

y

incre

asin

g g

radu

ally

this

rate

for

a g

ive

n level of

vib

ration.

8

Pro

duct str

ength

an

d e

nvironm

ent str

ess v

aria

bili

ties

are

or

are

n’t c

onsid

ere

d

( in

th

e p

rocess o

f deri

vin

g t

he t

est severity

)

no

9

Does th

e test

brin

g k

now

ledge o

n r

elia

bili

ty

para

mete

rs ?

no

10

D

oes th

e test co

nsum

e tota

lly o

r p

art

ially

the life

pote

ntial ot th

e e

quip

ment subm

itte

d to t

est ?

Yes , t

he p

roduct

und

er

test is

norm

ally

destr

oye

d

11

m

ain

norm

s , s

tandard

s, te

chnic

al re

fere

nces r

ela

tive

to th

is t

yp

e o

f te

sts

no

15

se

pte

mb

er

20

05

pa

ge

23

/31

D

e v e l o p m e n t T e s t

1

Test obje

ctive

(purp

ose,d

efinitio

n…

) O

bje

ctive

: to

make q

uic

ker

investigations in r

educin

g t

he test

dura

tio

n.

Princip

le: th

e p

roduct

is s

ubje

cte

d to

cond

itio

ns of

use o

r to

co

nstr

ain

ts o

f en

viro

nm

ent am

plif

ied in o

rder

to a

ccele

rate

th

e

mechanis

ms o

f fa

ilure

an

d t

o r

educe t

he n

ecessary

dura

tio

n to

estim

ate

som

e b

eh

avio

ral chara

cte

ristics o

f th

e p

rod

uct in

th

e n

orm

al

conditio

ns o

f em

plo

yment

Don’t m

ake the c

onfu

sio

n b

etw

ee

n th

e “

accele

rate

testing”

with

“h

igh

ly a

ccele

rate

testing”

wh

ose a

im is v

ery

diffe

rent (

see §

XX

).

The a

ccele

rate

testing h

as n

oth

ing

to d

o w

ith E

SS

or

hig

hly

accele

rate

d tstin

g.

Cond

itio

ns o

f ap

plic

ation :

K

no

w t

he

anal

yti

cal

mo

del

makin

g t

he

rela

tio

n b

etw

een

the

dam

age

wit

h t

he

am

pli

tud

e an

d d

ura

tio

n o

f th

e ap

pli

ed c

ond

itio

ns

.

Kno

w t

he

val

ue

of

the

par

am

ete

rs i

nvo

lve

in t

hese

mo

del

s

The

pro

vo

ked

mec

hanis

ms

of

fail

ure

have

to b

e re

pre

senta

tive

of

tho

se a

risi

ng

in t

he

no

rmal

co

nd

itio

ns

of

em

plo

ym

ent

The

phen

om

ena

of

inte

ract

ion

s b

etw

een s

ever

al c

onst

rain

ts o

f em

plo

ym

ent

or

of

envir

on

men

t m

ust

be

taken

into

acc

ou

nt.

Testing is d

one u

ntil fa

ilure

s take p

lace a

nd t

he k

ey is t

o u

nders

tan

d th

e f

ailu

res a

nd th

eir r

ela

tionsh

ip to t

he a

pp

lied s

tresses.

Accele

rate

d life testing

is p

erf

orm

ed to o

bta

in info

rmation o

n th

e p

roduct (c

om

ponent, m

odule

, syste

m e

tc.)

lifetim

e d

istr

ibution o

r a

part

icu

lar

relia

bili

ty p

ara

mete

r in

a tim

ely

manner.

This

can b

e d

on

e in t

wo d

iffe

rent w

ays

or

in a

com

bin

ation

of

them

:

- usin

g t

ime c

om

pre

ssio

n, fo

r exam

ple

by c

han

gin

g th

e length

of

on a

nd o

ff c

ycle

s

- accele

rating

the

lo

ad

ing c

onditio

ns

The p

urp

ose o

f lif

e t

estin

g i

s t

o i

dentify

the r

ele

vant

failu

re m

echanis

ms t

hat

would

occur,

and c

orr

ela

te t

hese w

ith t

he p

oin

t in

th

e

pro

duct’s l

ife t

he f

ailu

re w

ould

occur.

All

the s

tresses d

urin

g t

he p

roduct’s w

hole

life c

ycle

need t

o b

e a

ddre

ssed –

e.g

. tr

ansp

ort

ation,

sto

rage a

nd t

he a

ctu

al

use c

onditio

ns.

These c

onditio

ns u

sually

inclu

de d

iffe

rent

and c

hang

ing t

em

pera

ture

s,

hum

idity,

mechanic

al

str

esses (

vib

rations, sh

ock, bum

ps e

tc.)

, ele

ctr

ica

l a

nd e

lectr

om

agnetic p

henom

ena e

tc.

2

What is

drivin

g y

ou

for

choosin

g t

he t

est?

To b

e g

en

era

lised

- tim

e to m

ark

et of

the p

roduct

AT

TA

CH

ME

NT

4 a

cce

lera

ted

te

sts

; p

rop

osa

l :

He

lge

Pa

lmen

15

se

pte

mb

er

20

05

pa

ge

24

/31

3

Le

ve

l o

f a

ssem

bly

of th

e p

rod

uct

su

bm

itte

d t

o t

est

Qu

ite

ofte

n th

e g

rea

test b

en

efit

of

accele

rate

d te

sts

( in

term

of

kno

wle

dg

e a

cq

uis

itio

n)

is a

ch

ieve

d b

y p

erf

orm

ing

tests

at

the

lo

we

st le

ve

l

of

assem

bly

. T

est sh

ou

ld a

lso

be

ma

de

ea

rly in t

he p

rodu

ct de

ve

lop

me

nt p

roce

ss.

Ho

we

ve

r, t

estin

g s

ho

uld

be

co

ntin

ue

d d

uri

ng

th

e

diffe

ren

t ph

ase

s o

f th

e p

rod

uct d

eve

lopm

en

t –

fro

m d

esig

n p

ha

se (

testing

don

e o

n e

arly p

roto

typ

es)

to m

anu

factu

rin

g q

ua

lific

atio

n a

nd

/or

to p

erio

dic

qu

alif

ica

tio

n te

sts

.

4

Nu

mb

er

of

ite

ms s

ubm

itte

d t

o te

st

Fo

r sta

tistica

l co

nfide

nce

th

e n

ee

d is o

fte

n h

igh

er

tha

n w

ha

t is

pra

ctica

lly p

ossib

le ; a

bo

ut

five

be

ing a

min

imum

bu

t fe

w t

en

s w

ou

ld b

e

ne

ed

ed

.

In g

ene

ral o

ne ;

the

app

lica

tion

on

hig

he

r am

ou

nt

mig

ht b

e a

re

spo

nse

fo

r p

rodu

ct

va

ria

bili

ty c

on

sid

era

tion

s :

see

fo

llow

ing

§ 8

5

Typ

e o

f p

rod

uct

rele

va

nt

to b

e

su

bm

itte

d t

o t

he

te

st

( m

ass

vo

lum

e lo

w p

rice p

rodu

ct ,.

.)

ST

OP

All

typ

es.

6

Te

st

du

ratio

n (

da

ys,

we

eks,

mo

nth

s..

)

Accele

rate

d s

tress te

st can

be m

ade

va

ria

bly

in

da

ys o

r fe

w w

ee

ks.

Life

testin

g t

yp

ically

req

uir

es s

eve

ral w

ee

ks,

eve

n s

om

e m

on

ths.

7

Se

pa

rate

or

com

bin

ed

en

vir

onm

en

ts

Diffe

rent

typ

es o

f str

esses a

re n

ee

ded

to

pre

cip

ita

te t

he

diffe

ren

t fa

ilure

me

cha

nis

ms.

Pro

per

co

mb

ina

tion

of str

esse

s m

ay b

e u

se

d to

rea

lise

syn

erg

istic e

ffe

cts

– f

or

exa

mp

le t

he

rmal cyclin

g a

nd

vib

ratio

n.

Hu

mid

ity is a

lso

usua

lly a

pplie

d w

ith

hig

he

r o

r va

ryin

g te

mpe

ratu

re.

8

Pro

du

ct

str

en

gth

and

en

viro

nm

en

t

str

ess v

aria

bili

tie

s a

re o

r a

ren’t

co

nsid

ere

d

( in

the

pro

cess o

f de

rivin

g th

e t

est

se

ve

rity

)

Ye

s.

9

Do

es th

e t

est b

rin

g k

no

wle

dg

e o

n

relia

bili

ty p

ara

me

ters

?

Life

te

stin

g a

ims a

t g

ett

ing

an

estim

ate

of

for

exa

mp

le o

f th

e fa

ilure

ra

te (

or

MT

TF

, M

TB

F)

or

the

on

-set

of

we

ar-

out

me

chan

ism

s (

life t

ime

)

or

at

lea

st

the

re

leva

nt

failu

re m

ech

an

ism

s.

10

Do

es th

e t

est co

nsum

e t

ota

lly o

r

pa

rtia

lly t

he life

pote

ntia

l o

f th

e

eq

uip

men

t su

bm

itte

d t

o te

st

?

Accele

rate

d s

tress te

sts

an

d life

te

sts

are

de

str

uctive

.

11

ma

in n

orm

s , s

tan

dard

s, te

ch

nic

al

refe

rences r

ela

tive

to

this

typ

e o

f

tests

- E

nvir

on

men

tal te

sting

, acce

lera

ted

str

ess te

sts

: IE

C 6

00

68

-2 –

sta

nd

ard

se

ries

- M

ech

an

ical a

nd

clim

atic t

est m

eth

ods (

se

mic

on

ducto

r d

evic

es):

IE

C 6

07

49 s

tan

da

rd s

eri

es

15

se

pte

mb

er

20

05

pa

ge

25

/31

d

eve

lop

me

nt te

st

1)

Test

ob

jecti

ve

Develo

pm

ent

tests

are

use

d t

o d

ete

rmin

e t

he

aptitu

de

of

com

ponents

, m

ate

rials

and/o

r desig

ns t

o m

eet

the

requ

irem

ents

(fu

nctiona

l a

nd o

pera

tio

nal) o

f a

giv

en s

pecific

ation .

These

tests

ma

y pre

pare

for

the q

ualif

icatio

n,

or

the R

DG

T o

r re

liab

ility

dem

onstr

ation ,

but

not

only

: t

he

y a

lso c

an c

ontr

ibute

to

pre

pare

R&

D d

ecis

ions.

Outg

oin

g f

rom

the s

pecifie

d e

nvir

onm

enta

l re

qu

irem

ents

rela

tin

g t

o o

pera

tion,

tra

nsport

ation

an

d s

tora

ge,

the a

ppro

pri

ate

test

pro

ce

dure

s,

the s

tress levels

and t

he t

est dura

tion s

ha

ll be c

hose

n, consid

eri

ng t

he e

xperie

nces w

ith e

arlie

r de

ve

lopm

ent an

d th

e k

now

-ho

w o

f th

e t

est specia

lists

.

The t

est

results a

re u

sed t

o m

ake d

esig

n d

ecis

ions a

s w

ell

as t

o e

valu

ate

th

e "

Re

liab

ility

" and

/or

the "

Life T

ime"

of

a p

roduct

and

to p

rove t

he

rig

htn

ess o

f a

desig

n.

There

for

the t

est

results,

meth

ods,

too

ls a

nd c

ond

itio

ns s

ha

ll b

e d

ocum

ente

d a

nd s

tore

d o

n s

uch

a w

ay,

that

the p

roba

bili

ty o

f lo

osin

g o

r dis

tracting

then is v

ery

lo

w.

3)

Wh

at

is d

riv

ing

yo

u f

or

pe

rfo

rmin

g t

he t

est

?

The tests

are

do

ne d

urin

g t

he d

evelo

pm

ent and d

esig

n p

hase o

f a p

roje

ct

with

tw

o a

ims:

- to

de

term

ine the a

bili

ty o

f m

ate

rials

, com

ponents

an

d/o

r desig

ns to r

esis

t on

eff

ects

of

specifie

d e

nviro

nm

enta

l co

nditio

ns,

wh

ere

exp

eri

ence is m

issin

g

and/o

r calc

ula

tion o

r virtu

al sim

ula

tion is n

ot possib

le o

r not e

nou

gh a

ccura

te.

- to

de

term

ine the a

bili

ty o

f a

desig

n s

olu

tion t

o m

eet th

e f

unctiona

l re

quirem

ents

of

a g

ive

n s

pecific

atio

n.

While

bein

g a

n s

ubsta

ntia

l part

of

de

velo

pm

ent

costs

and

an i

mport

ant

desig

n t

ool,

it i

s n

ecessary

to

pla

n a

nd t

o b

udg

et

it a

t th

e v

ery

beg

inn

ing o

f a

develo

pm

ent pro

ject. T

he p

rincip

al in

put fo

r th

is p

lann

ing a

ctivity is t

he p

roduct sp

ecific

atio

n

3-

“L

ev

el o

f ass

em

bly

of

the p

rod

uct

su

bm

itte

d t

o t

est

Mate

rial, c

om

ponent

and s

ub a

ssem

blie

s.

4-N

um

ber

of

item

s s

ub

mit

ted

to

test

15

se

pte

mb

er

20

05

pa

ge

26

/31

In

gen

era

l on

e .

But

seve

ral

ma

y be r

eta

ine

d f

or

qualif

ication i

n o

rder

to r

edu

ce t

he d

ura

tion o

f it :

t

he

sequence

of

tests

app

lied t

o e

ach o

f th

em

must be in r

ela

tio

n w

ith t

he r

eal se

que

nce e

xpecte

d in

the

fie

ld

5-T

yp

e o

f p

rod

uct

rele

van

t to

be s

ub

mit

ted

to

th

e t

est

( m

ass v

olu

me l

ow

pri

ce p

rod

uct

,..)

:

Not re

levant fo

r th

ose c

onstr

ain

s c

overe

d b

y o

ther

spe

cifie

d te

sts

( w

hic

h m

ust be s

tate

d in th

e test

pla

n)

su

ch a

s h

igly

accele

rate

d tests

, …

;

6-

Test

du

rati

on

(d

ays, w

eeks, m

on

ths..

) :

D

ep

end

ing o

f :

• w

hat

is the

go

al of

the s

pecific

develo

pm

ent te

st

• t

he t

yp

e o

f te

st : e

nd

ura

nce

( s

evera

l h

ours

or

da

ys)

, re

liab

ility

( in

ge

nera

l 10

tim

es the s

pecifie

d M

TB

F f

or

one e

quip

ment or

10/n

for

n e

qu

ipm

ents

)

7-S

ep

ara

te o

r co

mb

ined

en

vir

on

men

ts

As m

uch a

s p

ossib

le :

to b

e

sep

ara

ted ;

not

possib

le i

n s

om

me s

pecific

cases :

pre

sence o

f poly

mer

mate

ria

l in

a s

uspe

nsio

n (

req

uires v

ibra

tio

n a

nd

tem

pera

ture

) …

To a

llow

to d

ete

rmin

e t

he e

ffect

of

sin

gle

str

ess f

acto

rs o

n a

mate

rial

or

item

respective

ly t

o a

vo

id t

he r

ecip

rocal

influe

nce o

f severa

l str

esses,

the t

est

conditio

ns a

re u

su

ally

specia

l la

b c

ond

itio

ns, n

ot e

qua

l to

th

e r

ea

l en

vironm

enta

l cond

itio

ns o

f th

e p

rod

uct.

Rem

ark

: C

om

bin

ed t

ests

(H

um

idity/T

em

pera

ture

; V

ibra

tio

n/T

em

pera

ture

etc

.) a

re a

lso o

ften u

sed,

but

norm

ally

ap

plie

d o

n t

he f

ina

l pro

duct

and n

ot

for

the

purp

ose s

tate

d o

ut

un

der

poin

t 1).

8-P

rod

uct

str

en

gth

an

d e

nv

iro

nm

en

t str

es

s v

ari

ab

ilit

ies a

re o

r a

ren

’t c

on

sid

ere

d (

in

th

e p

roce

ss o

f d

eri

vin

g t

he t

est

sev

eri

ty)

To b

e s

een n

ext tim

e

9 -

Do

es t

he t

est

bri

ng

kn

ow

led

ge o

n r

eliab

ilit

y p

ara

mete

rs ?

Yes if

the

test

is d

ed

icate

d t

o R

elia

bili

ty g

row

th

15

se

pte

mb

er

20

05

pa

ge

27

/31

10-D

oes t

he

test

co

nsu

me t

ota

lly o

r p

art

iall

y t

he l

ife p

ote

nti

al o

f th

e e

qu

ipm

en

t su

bm

itte

d t

o t

est

?

The s

ub a

ssem

blie

s , c

om

ponen

t …

…..subm

itte

d t

o te

st are

no m

ore

ente

rin

g in t

he d

eliv

ery

for

the

custo

mer

. T

he

y m

ight be

used f

or

mock u

p, stu

dy o

r pro

toty

pe p

urp

oses,

11 -

main

no

rms ,

sta

nd

ard

s, te

ch

nic

al re

fere

nce

s r

ela

tiv

e t

o t

his

typ

e o

f te

sts

The r

esults o

f th

ese

tests

are

norm

ally

on

ly f

or

inte

rna

l use (

in g

en

era

l n

ot g

iven t

o th

e c

usto

mer)

. S

o t

he

re

fere

nce to t

he s

tandard

s is n

ot m

andato

ry .

No

know

n s

tandard

s a

re r

ela

ted to t

he d

evelo

pm

ent te

sts

.

15

se

pte

mb

er

20

05

pa

ge

28

/31

Ac

ce

lera

ted

te

sts

pro

po

sa

l b

y H

en

ri G

rze

sko

wia

k

prin

cip

e

Co

nd

itio

ns o

f a

pp

lica

tio

n

Exp

ecte

d r

esu

lts

Ob

jective

: re

du

ce

th

e te

st

du

ratio

n

Prin

cip

le:

the

p

rod

uct

is su

bje

cte

d to

co

nd

itio

ns

of

use o

r to

co

nstr

ain

ts o

f

en

viro

nm

ent

am

plif

ied

in

o

rde

r to

acce

lera

te

the

m

ech

an

ism

s

of

failu

re

an

d t

o r

ed

uce

th

e n

ece

ssa

ry d

ura

tion

to

estim

ate

som

e

beh

avio

ral

ch

ara

cte

ristics

of

the

pro

du

ct

in

the

no

rma

l co

nd

itio

ns o

f em

plo

ym

en

t

Kn

ow

th

e

an

aly

tica

l m

ode

l m

akin

g

the

re

latio

n b

etw

ee

n th

e sp

ee

d of

da

ma

ge

w

ith

th

e

am

plit

ud

e

of

the

ap

plie

d c

ond

itio

ns

Kn

ow

th

e

va

lue

of

the

pa

ram

ete

rs

invo

lve

in

th

ese

mo

de

ls

The

pro

vo

ke

d m

ech

anis

ms o

f fa

ilure

ha

ve

to

b

e

rep

rese

nta

tive

of

tho

se

arisin

g in

th

e no

rma

l co

nd

itio

ns of

em

plo

ym

en

t

The

p

hen

om

en

a

of

inte

ractio

ns

be

twe

en

se

ve

ral

co

nstr

ain

ts

of

em

plo

ym

en

t o

r of

en

viro

nm

en

t m

ust

be

ta

ke

n in

to a

ccou

nt.

Eva

lua

tio

n

of

the

be

ha

vio

ral

ch

ara

cte

ristics of

a pro

du

ct

in

the

no

rma

l co

nd

itio

ns

of

em

plo

ym

en

t,

it

for

the

co

mpa

tib

le

pe

rio

ds

with

th

e

ca

len

da

r co

nstr

ain

ts a

sso

cia

ted

to t

he

ph

ase

of

de

ve

lop

men

t of

the

pro

du

ct

15

se

pte

mb

er

20

05

pa

ge

29

/31

__

___

__

__

___

__

__

__

__

___

__

__

__

__

___

__

__

__

__

GU

IDE

En

vir

on

men

tal

Str

ess S

cre

en

ing

fo

r E

lectr

on

ic E

qu

ipm

en

t

usin

g H

igh

ly A

cc

ele

rate

d T

ests

__

___

__

__

___

__

__

__

__

___

__

__

__

__

___

__

__

__

__

January

20

06 E

ditio

n

Mem

bers

of

the A

ST

E E

nvir

onm

enta

l S

tress S

cre

en

ing C

om

mitte

e

havin

g p

art

icip

ate

d in th

e im

ple

menta

tio

n o

f th

is D

ocu

ment

Com

mitte

e P

resid

ent :

Danie

l G

OU

LE

T

T

hale

s D

ivis

ion A

éro

sp

ace

C

om

mitte

e m

em

bers

:

Serg

e B

LA

ZE

JE

WS

KI

Johnson C

ontr

ol

Vin

ce

nt D

ER

OU

ET

F

lextr

on

ics

Fra

ncis

DU

PO

UY

Serm

a T

echnolo

gie

s

Joëlle

DU

SS

AU

LT

A

irb

us

Cla

ude G

IGO

UX

Im

dR

-SD

F

Fabrice G

UE

RIN

IS

TIA

P

hili

pp

e J

EA

NP

IER

RE

E

mitech

Phili

pp

e P

OU

GN

ET

V

alé

o V

EM

S

Jacques R

ING

LE

R

Rin

gle

r C

onsu

ltin

g

Jean M

arie R

OU

RE

V

alé

o V

EC

S / C

EE

Lio

nel S

IMO

N

S

ole

ctr

on

F

rédéric T

RE

NIT

EC

ET

15

se

pte

mb

er

20

05

pa

ge

30

/31

Co

nte

nts

1 ..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

In

tro

du

cti

on

an

d h

isto

rical b

ackg

rou

nd

5

2 ..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

...

Ob

ject

6

3 ..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. D

om

ain

of

ap

plicati

on

6

4 ..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. T

erm

ino

log

y

6

5 ..

....

.. R

em

ind

er

of

the e

nvir

on

men

tal

str

ess s

cre

en

ing

ob

jecti

ves a

nd

pri

ncip

les

7

6 ..

....

....

....

....

....

....

....

....

....

....

....

. T

he E

SS

op

era

tio

ns a

t vari

ou

s s

tep

s o

f *a

ssem

bly

*

9

6.1

The n

otions o

f hom

og

eneous / h

ete

rog

eneous p

roducts

in fro

nt of

resis

tance t

o c

onstr

ain

ts

9

6.2

....

....

....

....

....

....

....

....

....

....

....

....

...

Incid

ence o

n the testing m

eans s

pecific

ation:

11

7 ..

....

....

. Ju

sti

ficati

on

of

the “

Hig

hly

accele

rate

d e

nvir

on

men

tal

str

ess s

cre

en

ing

” 1

3

7.1

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

... C

om

parison o

f th

e tw

o m

eth

ods

13

7.1

.1 ..

....

....

....

....

....

....

.. “

Conventional environm

enta

l str

ess s

cre

enin

g”

meth

od

14

7.1

.2 ..

....

....

....

....

. “H

ighly

accele

rate

d e

nvironm

enta

l str

ess s

cre

enin

g”

meth

od

16

7.2

....

....

....

....

....

....

....

...

Com

parison o

f th

e e

nvironm

ent str

ess s

cre

enin

g m

eth

ods

18

7.3

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. O

ther

advanta

ges

19

7.4

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. P

ote

ntial pro

ble

ms a

nd p

recautions:

19

8 ..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

.. I

nit

ial E

SS

pro

file

set

up

20

8.1

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

...

ES

S p

rofile

phases 2

0

8.2

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. S

ele

ction o

f th

e a

pplic

able

constr

ain

ts:

21

8.3

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

Choic

e o

f th

e E

SS

constr

ain

ts levels

21

8.3

.1 ..

....

....

....

....

....

....

....

....

....

....

....

...

Fix

ed t

em

pera

ture

s c

ases (

warm

or

cold

)

22

8.3

.2 ..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. T

herm

al cycle

s c

ases

24

15

se

pte

mb

er

20

05

pa

ge

31

/31

8.3

.3

Pseudo-u

npre

dic

table

vib

rations c

ases (

3 a

xes, 6 d

eg

rees o

f fr

eedom

) ..

...

27

8.3

.4

Therm

al cycle

s c

om

bin

ed w

ith v

ibra

tions 3

axes 6

deg

rees o

f fr

eedom

: ..

...

28

8.4

....

....

....

....

....

....

....

....

....

....

....

....

.. C

onstr

ain

ts h

arm

lessness o

n s

ound p

roducts

2

9

9 ..

....

....

....

....

....

....

....

....

....

....

....

...

Ch

ara

cte

risti

cs o

f th

e in

terf

aces u

sed

fo

r th

e E

SS

32

10 ..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

.. I

nit

ial p

rofi

le a

nd

testi

ng

mean

s v

ali

dati

on

3

3

10.1

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

...

Valid

ation o

f th

e E

SS

harm

lessness

34

10.2

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

.. V

alid

ation o

f th

e E

SS

effic

iency

36

11 ..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

...

Man

ag

em

en

t o

f th

e E

SS

op

era

tio

n

39

11.1

....

....

....

....

....

....

....

.. R

ealis

ation a

nd m

onitoring o

f th

e t

ests

, fa

ilure

s d

ete

ction

39

11.2

....

....

....

....

....

....

....

....

....

....

....

....

....

....

Applic

able

pro

cedure

s in c

ase o

f fa

ilure

s

40

11.3

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. C

apitalis

ation o

f th

e r

esults

40

11.4

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. T

he E

SS

optim

isation

42

12 ..

....

....

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lien

t /

su

pp

lier

inte

rface

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. R

esponsib

ilities a

nd c

ontr

actu

al m

odalit

ies

43

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. E

SS

pro

file

valid

ation t

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lio

gra

ph

ical re

fere

nces

45

Ap

pen

dix

es

Appendix

A:

E

SS

by s

am

plin

g

Appendix

B:

S

om

e o

rders

of m

ag

nitude

WG ESS report 45 brussels - CEEES · HOLY Michel retired/SSEE ... corresponding source, to Marco ,...

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Transcript of WG ESS report 45 brussels - CEEES · HOLY Michel retired/SSEE ... corresponding source, to Marco ,...