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Meyer Y.,Higher Institute of Mechanical Engineering, Paris | Collet M.,FEMTO ST Institute
Mechanical Systems and Signal Processing | Year: 2011

The sensitive electronic components used in military and aerospace applications endure some intense vibrations. These vibrations have some disturbing effects on the stability and on the service life of these devices. So, protecting these elements becomes a major economic and strategic stake. Vibration isolation can be applied to different levels of the on-board systems. Indeed, it is advisable to isolate electronic components either at the rack level or at the board level or at the component level. In this paper, the last solution is chosen because of low moving masses which imply low control energies. An active suspension system is located between the host board and the sensitive element to be isolated. This designed control system uses a simple Integral Force Feedback strategy. This vibration isolation control is stable for its collocated version and does not need a numerical model of the system to be controlled. Robustness of the system is asymptotically guaranteed. The proposed isolation device, made of alumina for passive structure and made of PZT and PVDF for transducing layers, is experimentally tested. Experimental performances are compared with theoretical performances. © 2010 Elsevier Ltd. All rights reserved.

Jaballi K.,University of Sfax | Jaballi K.,Higher Institute of Mechanical Engineering, Paris | Bellacicco A.,Higher Institute of Mechanical Engineering, Paris | Louati J.,University of Sfax | And 2 more authors.
Computers in Industry | Year: 2011

During the production of new part in an industrial environment, it results in a high percentage of scrap if manufacturing planning is not carried out properly. One of the major factors responsible for this phenomenon is tolerance synthesis. In this paper, we deal with tolerance synthesis, and especially tolerance type identified after transfer. An algorithmic Rational method for 3D Manufacturing Tolerancing Synthesis (R3DMTSyn), which is based on the use of the Technologically and Topologically Related Surface (TTRS) rules, is developed. The TTRS concept helps to generate only the necessary manufacturing specification needed to guarantee the respect of the functional specification studied. The manufacturing project is modeled by a graphical representation called the SPIDER GRAPH. With the SPIDER GRAPH, all active surfaces can be detected (machined and positioning surfaces), so it is possible to identify the location of the functional surfaces used in each functional specification. The construction or the determination of the tolerancing torsor, belonging to each active surface, contributes to the selection of the adequate case of associations. A semantic study is already done to identify all possible combinations or associations needed to locate surfaces during each phases. Finally, referring to the developed TTRS-Cars-Process and in every phase, one or more manufacturing specifications are generated until finishing the treatment of all surfaces (surface belonging to the functional condition, or intermediate surfaces). © 2011 Elsevier B.V. All rights reserved.

Canbaz B.,École Centrale Paris | Yannou B.,École Centrale Paris | Yvars P.-A.,Higher Institute of Mechanical Engineering, Paris
Proceedings of the ASME Design Engineering Technical Conference | Year: 2013

In distributed design systems, designers are related to each other through couplings, however they have limited control over the design variables. Any inconsistency in the design system can result in design conflicts through these couplings. Modeling designer attitudes can help to understand inconsistencies and manage conflicts in design processes. We expand the bottom-up design approach through agent-based modeling techniques to another level where designers can make decisions directly on their wellbeing values that represent how their desires are satisfied. Set-based design and constraint programming techniques are used to explore the imprecision of the design activities. Monte Carlo simulations are performed to evaluate the performance of our approach. The results show that the number of design conflicts and their harshness can be lowered when the design process is defined with our approach. Copyright © 2013 by ASME.

Berik P.,Johannes Kepler University | Benjeddou A.,Higher Institute of Mechanical Engineering, Paris
International Journal of Smart and Nano Materials | Year: 2010

An experimental benchmark is proposed for piezoelectric, direct-torsion actuation using mono-morph piezoceramic d15 shear patches. This is reached by designing and assembling an adaptive plate having two identical composite faces sandwiching a core made of connected six oppositely polarized (OP) piezoceramic d15 shear patches along the length. An electronic speckle pattern interferometry system was used to measure the static tip deflection of the adaptive sandwich composite plate that was mounted in a cantilever configuration and actuated in torsion by progressively applied voltages on the piezoceramic shear core electroded major surfaces. Then, the effective rate of twist was post-processed and proposed as an evaluation criterion for smart composites under piezoelectric torsion actuation. For verification of the experimental results, the proposed experimental benchmark was simulated using three-dimensional piezoelectric finite elements (FE) within ABAQUS® commercial software. The comparison of the obtained experimental and simulation results showed reasonable agreement, but the slight nonlinear experimental response was not confirmed by the linear FE analysis. The experimentally proved torsion actuation mechanism, produced by OP piezoceramic d15 shear patches, can be applied actively to prevent torsion in many applications, such as in wind turbines, helicopter blades, robot arms, flexible space structures, etc. © 2010.

Canbaz B.,École Centrale Paris | Yannou B.,École Centrale Paris | Yvars P.-A.,Higher Institute of Mechanical Engineering, Paris
Proceedings of the ASME Design Engineering Technical Conference | Year: 2011

In the New Product Development processes, there are usually interacting multiple actors with multiple design objectives. Design objectives of the actors can be contradictorily related and design modifications related to some objectives may generate negative impacts on the other actors. Therefore conflicts may occur. We present a multi-actor design platform that is capable of preventing potential conflicts with ensuring the satisfaction and progress of the actors at a certain level. An indicator of wellbeing is developed in order to indentify the satisfaction and progress states of the actors. We use Setbased design approach and Constraint Satisfaction Problem solving techniques to deal with the multi-actor, multi-objective design problem. We apply our collaborative design approach to a multi-actor multiobjective engineering design problem of a hollow cylindrical cantilever beam with a load applied at the unsupported end. Copyright © 2011 by ASME.

Berik P.,Johannes Kepler University | Benjeddou A.,Higher Institute of Mechanical Engineering, Paris
International Journal of Smart and Nano Materials | Year: 2011

Static d 15-shear actuated smart composites consisting of glass fiber/epoxy layers sandwiching piezoceramic shear patches-assembled cores were investigated experimentally and numerically. The piezoceramic cores were formed by connecting two or three patches with the same or opposite polarization directions. For each cantilevered benchmark the shear-induced transverse tip deflection, under increasing actuation voltage, ranging from 61.5 V to 198 V, was measured by an electronic speckle pattern interferometer system. The performance of the shear actuated smart composites was characterized by their shear-induced transverse deflection per length per voltage. It was found that this performance is much better at high voltages for which the response becomes nonlinear. For verification of the experimental results the proposed benchmarks were simulated within ABAQUS ® commercial code using three-dimensional piezoelectric finite elements. The comparison of the obtained experimental and simulation results show a nonlinear dependence of the transverse deflection for voltages higher than around 92 V. © 2011 Copyright Taylor and Francis Group, LLC.

Francois A.,Higher Institute of Mechanical Engineering, Paris | Lanthony A.,Higher Institute of Mechanical Engineering, Paris
Proceedings of 2014 International Conference on Interactive Collaborative Learning, ICL 2014 | Year: 2015

Collaborative Platform for Systems Engineering is a project funded by the French National Agency for Research under 'Investments for the future' program. PLACIS is the French acronym for this project and this is the official name of this project. It started in September 2012 and is managed by the Collegium Ile-de-France (composed of three engineering schools). This large-scale project promotes active learning and teaching through industrial, international and at-A-distance collaborative projects, carried out by engineer students. Since its beginning, it has gained in maturity: new students' projects, new partners, but also development of new tools like a future learning platform: a distributed learning environment adaptive, collaborative, semantic and social web 3.0 and an implementation of a toolbox for teachers to assess skills and knowledge in project-based learning with an Erasmus+ project in parallel. The objective is to develop or create the involvement of teachers and students into new teaching practices (project-based learning, problem-based learning; small private online courses) necessary for the implementation of an alternative to the traditional configuration courses / supervised work / practical classes. All these aspects enable us to see the first achievements of what is the main goal of the project: to train students not only to become classic engineers, but also to be able to understand multidisciplinary and industrial issues, to work in teams, with people from different cultures and, more generally, to be actors of their curricula and to move easily in today's and tomorrow's industrial world. © 2014 IEEE.

Benjeddou A.,Higher Institute of Mechanical Engineering, Paris
European Journal of Computational Mechanics | Year: 2011

An experimentally proved smart concept for piezoceramic direct torsion actuation is here numerically assessed with regards to the bonding and segmentation influence on its behavior and performance. The TRESCA and deflection criteria analysis indicates that the actuator sandwiching with composites contributes to its integrity enhancement, but in the cost of its performance reduction. It is also found that modeling the core inter-rows and composites inter-layers bonding is more influential than that of the core rows segmentation. The conducted open-circuit modal analysis confirms that the inter-rows adhesive softens the actuator, while the inter-layers one stiffens it. Besides, the conducted adhesive parametric analysis indicates that, as expected, the most influential bonding parameters are its thickness and shear modulus. © 2011 Lavoisier, Paris.

Yvars P.-A.,Higher Institute of Mechanical Engineering, Paris
ICED 11 - 18th International Conference on Engineering Design - Impacting Society Through Engineering Design | Year: 2011

In this paper we are studying a deterministic constraint based approach to solve Pareto bi-criterion optimization problems in design. After presenting the use of multi-objective optimization methods in design, the CSP method and the several ways to solve it is introduced. A quick overview of CSP application in product engineering is given too. Moreover, we introduce an optimization point of view for CSP and we propose a deterministic alternative to stochastic methods for solving Pareto biobjective system sizing problems. An example in mechanical system optimization is given via the case study of the Pareto bi-criterion optimal design of a bolt coupling. The case is modeled as a Constraint Satisfaction Problem on both discrete and real variables. Finally, the numerical results and the Pareto frontier are exposed.

Meftah R.,Higher Institute of Mechanical Engineering, Paris | Meyer Y.,Higher Institute of Mechanical Engineering, Paris
Mechanics of Advanced Materials and Structures | Year: 2013

In radar equipments and communication systems, quartz resonators are key components. So as to enhance the resonator performances, the development of accurate modelings taking into account the environment interaction (temperature, acceleration, magnetism,.) is one of the major economic and strategic stakes. The main idea is to produce a realistic modeling. In literature, a lot of modelings are based on finite element analysis. But, for industrial applications, it is essential to link these accurate modelings to electric simulation softwares, such as Spice. Moreover, it is necessary to develop a simple computation method in order to answer the industrial time constraints. The idea is to use a Butterworth-Van Dyke (BVD) model based on an electrical equivalent circuit with, as input data, the studied natural frequency and the antiresonance frequency of an accurate finite element modeling. For the numerical example, a SC-cut (Stress-Compensated cut) quartz resonator is studied in this article for its fundamental thickness-shear resonance, the third and the fifth overtone. The influence of the model mesh quality, the electrode mass-loading, and the acceleration sensitivity on the motional parameters are analyzed. First, the choice of the finite element number along the thickness axis is crucial for the computation accuracy of the motional parameters. Then, the more the electrode material has a high density, the more the mass loading has a strong influence of the motional parameter values. Finally, the motional parameters are not really influenced by the acceleration field. © 2013 Taylor & Francis Group, LLC.

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