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Tolerance verification permits to check the product conformity and to verify assumptions made by the designer. For conformity assessment, the uncertainty associated with the values of the measurands must be known. In fact, to evaluate form characteristics of large aircraft structure workpieces, sampling is required, so a measurement error is present: exact estimation of form characteristics would require complete knowledge of the surface. To minimise this measurement error, this paper presents a Krigingbased procedure to identify the minimum of measured points to check the conformity with a given confidence level. The proposed method is validated on a simple example of orientation tolerance and then performed to inspect the form defect on three large aircraft workpieces.

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Adhesives are being increasingly used in structural applications, especially in aerospace, automotive and naval structures, making their structural integrity an important issue. In-service loading histories of such structures usually contain low-energy impacts, repetition of which can significantly affect their performance. This paper deals with the behaviour of the toughened epoxy adhesive FM73 under repeated impacts, known as impact fatigue. Izod impact fatigue tests were performed on FM73 specimens in order to study the evolution of damage and to characterise this via measurable parameters, such as the maximum force and the contact time. A finite element model was developed to simulate the impact tests and this was used to calculate the dynamic strain energy release rate, which was compared with that determined using a simple analytical method. A relationship between the maximum dynamic strain energy release rate and impact fatigue crack growth rate was established that was used as the basis of an impact fatigue crack growth law.

Dans l'industrie automobile, la maîtrise de la fiabilité constitue un enjeu majeur sur le plan financier et sur l'image de marque. Des méthodes éprouvées existent pour estimer la probabilité de défaillance et valider expérimentalement les objectifs de fiabilité. Elles sont toutefois rarement utilisées de manière efficace car les acteurs du secteur ont du mal à comprendre les attentes de chacun et méconnaissent ces méthodes fondamentales. A la suite de ce constat, la Société des Ingénieurs de l'Automobile (SIA) a mandaté un groupe d'experts fiabilistes des sociétés AB VOLVO, HUTCHINSON, PSA, RENAULT, SECTOR et VALEO pour élaborer un guide d'aide à l'estimation et la validation de la fiabilité automobile. Ce guide propose une trame méthodologique illustrée par des exemples d'applications, des fiches pratiques et un glossaire définissant un vocabulaire de référence pour la fiabilité. Accessible à un large public, il s'adresse aux bureaux d'études, spécialistes essais, ingénieurs calculs, spécialistes SDF, managers et responsables qualité. Son ambition est d'être une référence pour la filière automobile afin que les acteurs précités puissent concevoir et valider de façon collective et efficace des produits fiables.

The digitalization of the economy in the past decades has made data availability grow and become more important. From the maintenance point of view, clients are more demanding, wanting systems that will not have breakdowns while reducing exploitation costs. This challenging scenario has pushed companies in the direction of more intelligent maintenance solutions that involve choosing the best course of action in terms of system availability. Nowadays, these solutions are usually called prescriptive maintenance. This term is vaguely defined and its use is often unjustified. In this article we will discuss what really characterizes prescriptive maintenance, review some of the work published with this term and propose a generic framework to guide the development of such solutions. In the end, we will illustrate the use of the generic framework in a practical case.