Calculation and analysis of assembly clearance based on nonideal surface discrete data

Calculation of assembly clearance is the basis of analysis on assembly problems, and the real assembly surface is the nonideal surface. In this paper, the concept of assembly clearance on nonideal surface is defined and the calculation algorithm of assembly clearance is designed. Based on the calculation, the concept of clearance surface is put forward to express the distribution of assembly clearance on nonideal surface as it can assist the analysis of assembly problems. Finally, the effectiveness of the algorithm is verified by the calculation of the assembly clearance between the surfaces of piston and cylinder

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

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

Optimum machine capabilities for reconfigurable manufacturing systems

Reconfigurable manufacturing systems constitute a new manufacturing paradigm and are considered as the future of manufacturing because of their changeable and flexible nature. In a reconfigurable manufacturing environment, basic modules can be rearranged, interchanged, or modified, to adjust the production capacity according to production requirements. Reconfigurable machine tools have modular structure comprising of basic and auxiliary modules that aid in modifying the functionality of a manufacturing system. As the product’s design and its manufacturing capabilities are closely related, the manufacturing system is desired to be customizable to cater for all the design changes. Moreover, the performance of a manufacturing system lies in a set of planning and scheduling data incorporated with the machining capabilities keeping in view the market demands. This research work is based on the co-evolution of process planning and machine configurations in which optimal machine capabilities are generated through the application of multi-objective genetic algorithms. Furthermore, based on these capabilities, the system is tested for reconfiguration in case of production changeovers. Since, in a reconfigurable environment, the same machine can be used to perform different tasks depending on the required configuration, the subject research work assigns optimum number of machines by minimizing the machining capabilities to carry out different operations in order to streamline production responses. An algorithm has also been developed and verified on a part family. As a result of the proposed methodology, an optimized reconfigurable framework can be achieved to realize optimal production of a part family. Finally, the proposed methodology was applied on a case study and respective conclusions were drawn

Integrated product process design applied to the selection of additive manufacturing processes

Cette recherche vise à proposer une approche intégrée permettant la prise en compte simultanée des paramètres Produits / process dans le cadre d’une fabrication par ajout de matière. Le développement produit est en profonde mutation, prenant en compte les contraintes de personnalisation, de temps de mise sur le marché de plus en plus court, la volonté d’une approche eco-responsable etc. Ce changement de paradigme conduit à s’intéresser au choix du couple matériau /process dès la phase de conception afin de prendre en compte les contraintes liées au procédé identifié. Cette approche multi critère s’intéresse à la fois au couple matériau procédé mais prend en compte les aspect fonctionnels de la pièce. Ainsi ce travail de thèse présente une méthodologie de décision générique, basée sur des outils de prise de décision multicritères, qui peut non seulement proposer une solution satisfaisant les contraintes liées aux matériaux, processus et processus par addition de matière, mais propose également de servir de guide aux concepteurs permettant un choix raisonné basé sur des combinaisons matériau-machine orientées conception et obtenu à partir d’une base de données de 38 fournisseurs internationaux de machine de fabrication par ajout de matière.The doctoral research focuses to build an integrated approach that can simultaneously handle the product and process parameters related to additive manufacturing (AM). Since, market dynamics of today are constantly evolving, drivers such as mass customization strategies, shorter product development cycles, a large pool of materials to choose from, abundant manufacturing processes, etc., 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 AM guidelines. As several criteria, material attributes and process functionality requirements are involved for decision making in the industries, the thesis introduces a generic decision methodology, based on multi-criteria decision-making tools, that can 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 combinations from a database of 38 renowned AM vendors in the world today

Intégration Produit-Process appliquée à la sélection de procédés de Fabrication Additive

The doctoral research focuses to build an integrated approach that can simultaneously handle the product and process parameters related to additive manufacturing (AM). Since, market dynamics of today are constantly evolving, drivers such as mass customization strategies, shorter product development cycles, a large pool of materials to choose from, abundant manufacturing processes, etc., 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 AM guidelines. As several criteria, material attributes and process functionality requirements are involved for decision making in the industries, the thesis introduces a generic decision methodology, based on multi-criteria decision-making tools, that can 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 combinations from a database of 38 renowned AM vendors in the world today.Cette recherche vise à proposer une approche intégrée permettant la prise en compte simultanée des paramètres Produits / process dans le cadre d’une fabrication par ajout de matière. Le développement produit est en profonde mutation, prenant en compte les contraintes de personnalisation, de temps de mise sur le marché de plus en plus court, la volonté d’une approche eco-responsable etc. Ce changement de paradigme conduit à s’intéresser au choix du couple matériau /process dès la phase de conception afin de prendre en compte les contraintes liées au procédé identifié. Cette approche multi critère s’intéresse à la fois au couple matériau procédé mais prend en compte les aspect fonctionnels de la pièce. Ainsi ce travail de thèse présente une méthodologie de décision générique, basée sur des outils de prise de décision multicritères, qui peut non seulement proposer une solution satisfaisant les contraintes liées aux matériaux, processus et processus par addition de matière, mais propose également de servir de guide aux concepteurs permettant un choix raisonné basé sur des combinaisons matériau-machine orientées conception et obtenu à partir d’une base de données de 38 fournisseurs internationaux de machine de fabrication par ajout de matière

Smart Warehouse Management System: Architecture, Real-Time Implementation and Prototype Design

The world has witnessed the digital transformation and Industry 4.0 technologies in the past decade. Nevertheless, there is still a lack of automation and digitalization in certain areas of the manufacturing industry; in particular, warehouse automation often has challenges in design and successful deployment. The effective management of the warehouse and inventory plays a pivotal role in the supply chain and production. In the literature, different architectures of Warehouse Management Systems (WMSs) and automation techniques have been proposed, but most of those have focused only on particular sections of warehouses and have lacked successful deployment. To achieve the goal of process automation, we propose an Internet-of-Things (IoT)-based architecture for real-time warehouse management by dividing the warehouse into multiple domains. Architecture viewpoints were used to present models based on the context diagram, functional view, and operational view specifically catering to the needs of the stakeholders. In addition, we present a generic IoT-based prototype system that enables efficient data collection and transmission in the proposed architecture. Finally, the developed IoT-based solution was deployed in the warehouse of a textile factory for validation testing, and the results are discussed. A comparison of the key performance parameters such as system resilience, efficiency, and latency rate showed the effectiveness of our proposed IoT-based WMS architecture

Smart Warehouse Management System: Architecture, Real-Time Implementation and Prototype Design

The world has witnessed the digital transformation and Industry 4.0 technologies in the past decade. Nevertheless, there is still a lack of automation and digitalization in certain areas of the manufacturing industry; in particular, warehouse automation often has challenges in design and successful deployment. The effective management of the warehouse and inventory plays a pivotal role in the supply chain and production. In the literature, different architectures of Warehouse Management Systems (WMSs) and automation techniques have been proposed, but most of those have focused only on particular sections of warehouses and have lacked successful deployment. To achieve the goal of process automation, we propose an Internet-of-Things (IoT)-based architecture for real-time warehouse management by dividing the warehouse into multiple domains. Architecture viewpoints were used to present models based on the context diagram, functional view, and operational view specifically catering to the needs of the stakeholders. In addition, we present a generic IoT-based prototype system that enables efficient data collection and transmission in the proposed architecture. Finally, the developed IoT-based solution was deployed in the warehouse of a textile factory for validation testing, and the results are discussed. A comparison of the key performance parameters such as system resilience, efficiency, and latency rate showed the effectiveness of our proposed IoT-based WMS architecture

An ontology-based modelling and reasoning framework for assembly sequence planning

International audienc

Numerical and Experimental Analysis of Drag and Lift Forces on a Bullet Head

The bullet head plays a principal role in the modern enlargement of an efficient bullet. A bullet’s main design parameters depend upon the lift and drag forces acting on the head. The factors in a bullet’s shape design that affect bullets’ lift and drag forces are essential in aerodynamics, especially in ballistics. Therefore, the effect of wind on the lift and drag forces acting on the bullet, and the role of the bullet head to allow the bullet to travel efficiently through the wind, need to be investigated. This work discusses the parameters that affect the lift and drag force on the bullet. Simulations are performed in Ansys Fluent by varying the key parameters of the bullet head, i.e., the length and angle of attack, while keeping the air velocity at 5.2 m/s. The simulation outcome shows that the size of the bullet and the angle of attack are important factors related to the drag force. Therefore, this work predicts the inspection of a bullet under distinct wind conditions. An evaluation is performed to scrutinize the effect of design factors on the system execution of the bullet and its constructive flight path. It is concluded that when increasing the length of the bullet and its angle of attack (AOA), the drag force and lift forces increase drastically, contributing to the inefficiency of the bullet’s accuracy and penetrating power. A new design is also proposed in which the drag forces are reduced to the minimum