Fixator : Dispositif d'aide à la montée et/ou à la descente de personne

Fixator : Dispositif d'aide à la montée et/ou à la descente de personne

Fixator : Dispositif d'aide à la montée et/ou à la descente de personne

Fixator : Dispositif d'aide à la montée et/ou à la descente de personne

A design methodology for parts using additive manufacturing

Additive Manufacturing (AM) allows designer to sidestep several design requirements and to create free forms, hollow parts or direct assemblies. This process also allows direct recycling of plastic into new parts, which eases the raw material supply. However, although several methodologies are used to redes-ign products and parts, none is dedicated to a real design of parts and products in AM. At first, we will sug-gest the base of a new design methodology for an end-user who wants to create a product or a part in AM. Then, we will show an example of using our methodology. Finally, we will conclude on the limits of this methodology and on our next work to validate our methodology

Méthodologie de conception pour la réalisation de pièce en Fabrication Additive

La Fabrication Additive (FA) permet de se libérer d’un grand nombre de contraintes de conception concernant les formes libres, les formes creuses ou encore les assemblages. Ce procédé permet également le recyclage direct de certaines matières plastique, ce qui facilite l’approvisionnement en matière première. Cependant, bien que certaines méthodologies permettent de reconcevoir une pièce pour la réaliser en FA, il n’existe pas encore de véritable méthodologie de conception dédiée à la FA. Dans un premier temps, nous proposerons un travail prospectif sur les bases d'une méthodologie pour un utilisateur final souhaitant concevoir des pièces visant à être réalisée en Fabrication Additive. Nous exposerons ensuite un cas d’utilisation permettant d’illustrer nos propos. Enfin, nous conclurons sur les limites de cette méthodologie et sur les travaux à venir permettant de valider notre méthodologie

Méthodologie de conception pour la réalisation de pièce en Fabrication Additive

La Fabrication Additive (FA) permet de se libérer d’un grand nombre de contraintes de conception concernant les formes libres, les formes creuses ou encore les assemblages. Ce procédé permet également le recyclage direct de certaines matières plastique, ce qui facilite l’approvisionnement en matière première. Cependant, bien que certaines méthodologies permettent de reconcevoir une pièce pour la réaliser en FA, il n’existe pas encore de véritable méthodologie de conception dédiée à la FA. Dans un premier temps, nous proposerons un travail prospectif sur les bases d'une méthodologie pour un utilisateur final souhaitant concevoir des pièces visant à être réalisée en Fabrication Additive. Nous exposerons ensuite un cas d’utilisation permettant d’illustrer nos propos. Enfin, nous conclurons sur les limites de cette méthodologie et sur les travaux à venir permettant de valider notre méthodologie

Support optimization for additive manufacturing: application to FDM

Purpose This paper aims to present a new methodology to optimize the support generation within the FDM process. Design/methodology/approach Different methods of support generation exist, but they are limited with regards to complex parts. This paper proposes a method dedicated to support generation, integrated into CAD software. The objective is to minimize the volume of support and its impact on a part’s surface finish. Two case studies illustrate the methodology. The support generation is based on an octree’s discretization of the part. Findings The method represents a first solid step in the support optimization for a reasonable calculation time. It has the advantage of being virtually automatic. The only tasks to be performed by the designer are to place the part to be studied with respect to the CAD reference and to give the ratio between the desired support volume and the maximum volume of support. Research limitations/implications In the case studies, a low gain in manufacturing time was observed. This is explained by the honeycomb structure of the support generated by a common slicing software whilst the proposed method uses a “full” structure. It would be interesting to study the feasibility of an optimized support, with a honeycomb structure but with a preservation of the surface which is in contact with the part. Originality/value This solution best fits the needs of the designer and manufacturer already taking advantage of existing solutions. It is adaptable to any part if the withdrawal of support is taken into account. It also allows the designer to validate the generation of support throughout the CAD without breaking the digital chain

Additive manufacturing technology: the status, applications, and prospects

Additive manufacturing (AM) has first emerged in 1987 with the invention of stereolithography. The AM is an important, rapidly emerging, manufacturing technology that takes the information from a computer-aided design (CAD) and builds parts in a layer-by-layer style. As this technology offers many advantages such as manufacturing of complex geometries, reducing manufacturing cost and energy consumption, it has transformed manufacturing from the mass production to the mass customization. Also, it has found wide applications in several fields although some drawbacks. This paper presents the state of the art of the different AM processes, the material processing issues, and the post-processing operations. A comparison between AM and conventional processes is presented as well. We finish by presenting some prospects of this technology such as hybrid manufacturing and 4D printing

Integrated design-oriented framework for Resource Selection in Additive Manufacturing

Resource selection (RS) is one of the prime phases of product design that have substantiating impact on the manufacturing of products. Material and manufacturing process selection are considered an important ingredient of RS and must be dealt with in early stages of design. Since, emerging technologies such as Additive Manufacturing (AM) have re-defined the potentials of manufacturing by re-orienting market drivers such as high part-complexity needs, individualization, shorter product development cycles, abundant materials and manufacturing processes, diverse streams of applications, etc., it is imperative to select the right compromise of materials, manufacturing processes and associated machines in early stages of design considering the Design for Additive Manufacturing guidelines. As several criteria, material attributes and process functionality requirements are involved for decision making in the industries today, an integrated design-oriented framework is proposed in this paper for RS in AM to structure design knowledge pertaining to each stage of design process; conceptual, embodiment and detail designs. However, more focus will be kept on the conceptual and embodiment design phases. Moreover, axioms are defined to aid in decision making and help in extracting the rules associated with each of the design criteria. The framework is aimed to act as a guideline for designers in the AM industry to provide design oriented and feasible material-machine-process combinations

Geometrical deviation identification and prediction method for additive manufacturing

This work is supported in part by the scholarship from CSC under the Grant CSC N°201406020103.Purpose – One major problem preventing further application and benefits from additive manufacturing (AM) nowadays is that AM build parts always end up with poor geometrical quality. To help improving geometrical quality for AM, this study aims to propose geometrical deviation identification and prediction method for AM, which could be used for identifying the factors, forms and values of geometrical deviation of AM parts. Design/methodology/approach – This paper applied the skin model-based modal decomposition approach to describe the geometrical déviations of AM and decompose them into different defect modes. On that basis, the approach to propose and extend defect modes was developed. Identification and prediction of the geometrical deviations were then carried out with this method. Finally, a case study with cylinders manufactured by fused deposition modeling was introduced. Two coordinate measuring machine (CMM) machines with different measure methods were used to verify the effectiveness of the methods and modes proposed. Findings – The case study results with two different CMM machines are very close, which shows that the method and modes proposed by this paper are very effective. Also, the results indicate that the main geometrical defects are caused by the shrinkage and machine inaccuracy-induced errors which have not been studied enough. Originality/value – This work could be used for identifying and predicting the forms and values of AM geometrical deviation, which could help realize the improvement of AM part geometrical quality in design phase more purposefully

Integrated product-process design: Material and manufacturing process selection for additive manufacturing using multi-criteria decision making

Market dynamics of today are constantly evolving in the presence of emerging technologies such as Additive Manufacturing (AM). Drivers such as mass customization strategies, high part-complexity needs, shorter prod- uct development cycles, a large pool of materials to choose from, abundant manufacturing processes, diverse streams of applications (e.g. aerospace, motor vehicles, and health care) and high cost incurred due to manufac- turability of the part have made it essential to choose the right compromise of materials, manufacturing processes and associated machines in early stages of design considering the Design for Additive Manufacturing guidelines. There exists a complex relationship between AM products and their process data. However, the literature to-date shows very less studies targeting this integration. As several criteria, material attributes and process function- ality requirements are involved for decision making in the industries, this paper introduces a generic decision methodology, based on multi-criteria decision-making tools, that will not only provide a set of compromised AM materials, processes and machines but will also act as a guideline for designers to achieve a strong foothold in the AM industry by providing practical solutions containing design oriented and feasible material-machine com- binations from a current database of 38 renowned AM vendors in the world. An industrial case study, related to aerospace, has also been tested in detail via the proposed methodology