25 research outputs found
FEM analysis to optimally design end mill cutters for milling of Ti-6Al-4V
No full textThis paper presents an FEM analysis conducted for optimally designing end mill cutters through verifying the cutting tool forces and stresses for milling Titanium alloy Ti-6Al-4V. Initially, the theoretical tool forces are calculated by considering the cutting edge on a cutting tool as the curve of an intersection over a spherical/flat surface based on the model developed by Lee & Altinas [1]. Considering the lowest tool forces the cutting tool parameters are taken and optimal design of end mill is decided for different sizes. Then the 3D CAD models of the end mills are developed and used for Finite Element Method to verify the cutting forces for milling Ti-6Al-4V. The cutting tool forces, stress, strain concentration (s), tool wear, and temperature of the cutting tool with the different geometric shapes are simulated considering Ti-6Al-4V as work piece material. Finally, the simulated and theoretical values are compared and the optimal design of cutting tool for different sizes are validated. The present approach considers to improve the quality of machining surface and tool life with effects of the various parameters concerning the oblique cutting process namely axial, radial and tangential forces. Various simulated test cases are pr esented to highlight the approach on optimally designing end mill cutters
Collaborative Reverse Engineering Design Experiment Using PLM Solutions
No full textThe current climate of economic competition forces businesses to adapt to the expectations of their customers. To achieve this, in spite of the increasing complexity of mechanical systems, it becomes necessary, amongst other things, to reduce design time. Faced with new challenges, practices in design training must evolve to allow students to be mindful of these evolutions as well as to be able to manage projects in these new work environments. After presenting a state of the art of collaborative tools used in product design, our paper presents an experiment focusing on the reverse engineering of a complex mechanical product. This experiment was carried out between two centers of the Arts et Métiers ParisTech School of Engineering, located in Paris and Angers.Weanalyze the results obtained in this experiment and propose a collaborative environment that is well suited to our needs for design education, based on ‘‘Product Lifecycle Managament’’ (PLM) concepts. Finally, we present some modifications in collaborative design courses for our students, and we implement network modifications in order to significantly improve the ease of use of the design environment
Smart Tightening Development for Aeronautical Bolted Assemblies in an Industry 4.0
No full textInternational audienceSmart tightening development is part of the Industry 4.0 transformation with the introduction of smart tools, and preload in bolted assemblies is of major interest in today’s aircraft manufacturing process. So far, it has been difficult to estimate the importance of each parameter for tightening process quality, mainly because of the large number of combinations and configurations that exist. The present work aims at evaluating the effects and the interactions between different parameters that have to be taken in consideration in future torquing strategy. Many experimental tests have been conducted on an Automatica test bench using a Taguchi strategy and an analysis of the first main results is now presented, highlighting the complexity of the phenomena studied. All these points will help us to better understand tightening, so as to improve performance during installation, maintenance and repair
Belief and plausibility approximation methods for multidimensional functions
No full textInternational audienc
Method for rapid characterisation of cutting forces in end milling considering runout
No full textInternational audienc
A New Approach for Optimizing a Bipolar Charge Transport Model for Dielectric Materials: Theoretical Framework
No full textInternational audienceA bipolar charge transport model with two levels of traps (shallow and deep traps) is employed to describe and investigate the dynamic behavior of the space charge in low-density polyethylene (LDPE). This kind of model requires some initial experimental conditions alongside a set of parameters. An optimization method is used in order to provide the best precision for model parameters. Furthermore, the sensitivity of these parameters has been analyzed using an approach based on Sobol's method. In essence, this paper proposes a specific protocol that contributes to producing a global set of parameters able to provide the best approximate fit between experimental and simulated results. Net charge density is measured by the pulse electro-acoustic method (PEA) along with what is known as external charging current measurements. The simulated data are obtained by a bipolar charge transport model, which is developed for low-sensity polyethylene
Characterising the behaviour of workpieces under the effect of tangential cutting force during NC turning: Application to machining of slender workpieces
No full textInternational audienceTurning slender workpieces usually means a tailstock centre has to be used to in order to achieve geometric tolerances for cylindricality. Indeed, tight tolerances mean the grinding phase can be performed quicker or even rendered superfluous. To limit use of the tailstock centre, that limits tool access when producing slender workpieces using turning, knowledge of the spindle-chuck-workpiece assembly's behaviour is essential. It is proposed to characterise this assembly's behaviour under the action of machining loads in order to introduce a method that in some cases will dispense with the need to use the tailstock centre while keeping the geometric quality of the machined workpiece
Erratum to: TDP-43 gains function due to perturbed autoregulation in a Tardbp knock-in mouse model of ALS-FTD (Nature Neuroscience, (2018), 21, 4, (552-563), 10.1038/s41593-018-0113-5)
No full textIn the version of this article initially published, the footnote number 17 was missing from the author list for the two authors who contributed equally. Also, the authors have added a middle initial for author Justin R. Fallon and an acknowledgement to the Babraham Institute Imaging Facility and Sequencing Core Facility. The errors have been corrected in the HTML and PDF versions of the article
Cite Share Publisher Correction: TDP-43 gains function due to perturbed autoregulation in a Tardbp knock-in mouse model of ALS-FTD
No full textIn the version of this article initially published, the footnote number 17 was missing from the author list for the two authors who contributed equally. Also, the authors have added a middle initial for author Justin R. Fallon and an acknowledgement to the Babraham Institute Imaging Facility and Sequencing Core Facility. The errors have been corrected in the HTML and PDF versions of the articl
