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The industrialization of additive manufacturing strongly relies on the robustness of the process. In particular, the more complex Directed Energy Deposition (DED) processes offer great flexibility and higher build-up rates on the one hand, but on the other hand they pose challenges until a part can be printed with the desired properties. This paper adopts and compares different approaches, i.e. linear, sliding mode and model-based controller, for online process regulation of track height and width using a novel industrial sensor setup. Based on single track experiments, control parameters are determined and results of the closed loop analyzed. As a result, the linear controller shows the best performance and robustness. The performance for the track width can even be improved by a Linear Quadratic Gaussian (LQG) controller. Finally, the performance of the linear control strategy is tested with a complex motor cover part. Additionally, a digital twin representation shows the spatial representation of the process parameters and region of interests where thresholds or predefined process rules are violated. [ABSTRACT FROM AUTHOR]

Nowadays, the liquid nitrogen cooling in aluminium extrusion is a widely adopted industrial practice to increase the process productivity as well as to improve the extruded profile surface quality by reducing the profile exit temperatures. The cooling channels are commonly designed on the basis of die maker experience only, usually obtaining modest performances in terms of cooling efficiency. Trial-and-error approach is time and cost consuming, thus providing a relevant industrial interest in the development of reliable numerical simulations able to foresee and optimize the nitrogen cooling effect during the die design stage. In this work, an extensive experimental campaign was performed during the extrusion process of an AA6060 industrial hollow profile, in different conditions of nitrogen flow rate and ram speed. The monitored data (die and profile temperatures and extrusion load) were compared with the outputs of a fast and efficient numerical model proposed by the authors, and developed in the COMSOL Multiphysics code, able to compute not only the effect of nitrogen liquid flow but also the gaseous condition. The results of the simulations showed a good agreement with experimental data, and evidenced how far the experimental cooling channel design from an optimized condition was. [ABSTRACT FROM AUTHOR]

Digital twin has become essential to modern industrial developments and production paradigms. Digital twin provides support to users and processes in decision-making creating high-fidelity virtual models from physical objects in order to simulate their behaviors, predict their states, provide feedbacks, and if possible be optimized by themselves. The literature indicates an urgent need to develop digital twin applications. These applications require a digital platform that complies with DT requirements and allows all physical objects, virtual models, and industrial systems to communicate and integrate with each other. The contribution of this paper is to provide an analysis about digital twin (meaning and modeling), and to present a platform that works as: (1) a modern distributed system that runs as a cluster and can elastically scale to handle and integrate all the business applications, systems, and production data even the most massive data volumes; (2) a storage system that keeps data as long as necessary and provides real guarantees in delivery, persistence, performance (real time), reliability, and processing; (3) a real-time event-based platform that supports the requirements of digital twin applications including the management and support of different digital twin versions. [ABSTRACT FROM AUTHOR]

SKD11 is widely used in manufacturing die. With the development of industrial level, the size of the die is further reduced, and the difficult processing problem of high aspect ratio (HAR) micro-structures is exposed. Micro-milling is a suitable method for machining HAR micro-structures; however, the inevitable generation of burrs deteriorates the machined surface. Previous studies have mostly focused on the burr formation process of shallow grooves but have ignored HAR grooves. This paper investigated the burr formation mechanism in HAR (2:1) grooves on harden steel (SKD11). Due to the fact that the burr formation process was difficult to be observed in the actual micro-milling process, a finite element model was established. A corresponding experimental research was conducted, which revealed a good consistency between simulation and experimental results. Moreover, a new burr type was formed on the sidewall of the HAR groove, which was transformed from top burrs and was named as side burr. The results demonstrated that the chip flow on the rake face of the micro-mill was hindered by the sidewall, which caused chip crumbling, chip accumulation, and surface scraping, seriously affecting the burr formation mechanism. This paper revealed the burr formation mechanism for HAR grooves on SKD11, which provides basic data for manufacturing die with complex structure and small size. [ABSTRACT FROM AUTHOR]

Origami-based sheet metal (OSM) bending is an extension of rigid origami technique, where the final 3D structure is created from a single 2D flat pattern by bending. The key aspect of OSM is material discontinuity (MD), which helps achieve a unique dieless bending process. MD is a feature along bend line of blank sheet and it can be fabricated using laser or water jet cutting. Even though a number of successful implementations of OSM bending have been found, these cases are limited only to product development and industrial application. The mechanics of OSM bending with respect to parameters that define MD, blank sheet, as well as the bending process have not been studied. Thus, this study identifies parameters and investigates the effect of identified parameters associated with OSM bending. Parameters studied in this work include design parameters and process parameters. Design parameters are kerf-to-thickness (k/t) ratio, web-to-width (w/b) ratio, and thickness of sheet (t). These are associated with MD design. The process parameters are related to OSM bending process, and they include punch placement (t+g), offset distance (s), and punch radius (RP). Finite element analysis (FEA) is performed to investigate the effect of these parameters on the OSM bending process. The simulated OSM bending cases resulted in successful bending without using a die. The general recommendation is provided for selecting parameters of OSM bending based on results. In addition, the shape of MD is an important factor when designing the OSM bending process. [ABSTRACT FROM AUTHOR]

Taking smart manufacturing as a strategy for industrial development, China has put forward a people-oriented policy and launched a series of plans for smart manufacturing talent education (SMTE). The demand for smart manufacturing talents in ten priority areas and the industrial applications in China is very huge. Therefore, in this paper, a reference system of SMTE in China is presented, which includes discipline system, training system, practice system, and assessment system. In order to further refine the architecture of smart manufacturing system, a reference course system was proposed; the system contains seven layers, which are basic layer, technique layer, implementation layer, management layer, platform layer, application layer, and industrialization layer. Finally, nine stakeholders of the common operation body were investigated, and a reference implementation of SMTE in China was put forward. In this paper, the smart manufacturing talent education reference system, reference model, and related reference subsystems can be a very useful guideline for Chinese industry and education to design, set, and carry out the smart manufacturing talent education system. At the same time, the system has its reference value for the improvement of China's smart manufacturing system architecture. [ABSTRACT FROM AUTHOR]

Natural rubber latex (NRL) from Hevea brasiliensis can accelerate wound healing, but membranes made of NRL have shown low cellular interaction limiting their application as implants. By employing dipping layer-by-layer (LbL) technique, we were previously able to glow human fibroblast cells on NRL films. But this method is time consuming which hinders industrialization. Therefore, NRL films were produced using polyethyleneimine (PEI) by spraying (sp) LbL method, which proved to be 10 times faster than dipping techniques. Rinsed and non-rinsed sp films were produced by triggering the spray devices five times for each material. Both (PEI/NRL)5 and (PEI/NRL)15 spraying and dipping films were then analyzed by UV-vis, AFM, and contact angle measurements. In order to evaluate the cellular interaction, Vero cells were directly cultivated on the LbL films up to 24 h. Results showed that despite non-rinsed sp films having lower amount of material than dipping ones, Vero cells adhere similarly on both. Rinsed (PEI/NRL)5 sp films, on the other hand, presented higher amount of cellular attachment as well as smaller NRL particles on the films' surface. Thus, it was possible to increase cellular interaction of NRL and produce films 10 times faster by employing spraying LbL method. [ABSTRACT FROM AUTHOR]

The widespread use and continuous improvements of machine tools have had a significant impact on productivity in manufacturing industry ever since the Industrial Revolution. At the dawn of the new era of industrialization, the need to advance machine tools to a new level that accords to the concept of Industrie 4.0 has to be recognised and addressed. Muck like the different stages of industrialisation, machine tools have also gone through different stages of technological advancements, i.e., Machine Tool 1.0, Machine Tool 2.0 and Machine Tool 3.0. Industrie 4.0 pleads for a new generation of machines-Machine Tool 4.0. This paper describes some of the key and desired characteristics of Machine Tool 4.0 such as Cyber-physical Machine Tools, vertically and horizontally integrated machine tools and more intelligent, autonomous and safer machine tools. [ABSTRACT FROM AUTHOR]

The inertia of the stacked multi-degree-of-freedom platform imposes limitation on the achievable motion speed. To overcome this barrier, the unstable design becomes very attractive. This research presents a novel single-deck dual-axis linear motor platform that is capable of fast long-range motion. The platform is equipped with air-bearing design to achieve backlash-free operation. As a result, the positioning rigidity depends entirely on the performance of the servo system. A force distribution control is used to decouple the difference axis dynamics. This research also proposes a chain scattering description (CSD) setup to allow a pseudo-derivative feedback (PDF) control framework that is commonly used in industrial motion control for achieving high servo rigidity. An interesting finding is that our experiments show that without the help of complex piggyback piezoelectric stage, the single-deck platform design, with a stroke as large as 20 mm, can already reach a servo accuracy of ±60 and ±80 nm in the x- and y-axis and 600 μarcsec in the yaw axis. [ABSTRACT FROM AUTHOR]

The paper first presents a brief review of development courses of additive manufacturing technology and summarizes the development status and the application fields of additive manufacturing technology, then, according to the manufacturing methods, it focuses on the principles and characteristics of several main additive manufacturing technologies. This paper also analyzes the existing problems and challenges of additive manufacturing technology and its future development trend. This paper aims to provide references for the development direction of additive manufacturing technology in developing countries. [ABSTRACT FROM AUTHOR]

The quality of manufactured goods is one of the most important prerequisites that ensure industrial development of the countries, persistence, and the competitiveness of businesses in global market. For this reason, the lack of qualitative characteristics in the products of some manufacturing units causes the absence of their competition in the market. One of the major problems of the stone industry is lack of proper planning of management to produce high-quality stone and according to the international standards. Therefore, management techniques should be used to improve the quality of products and solve the existing problem. Despite multiple tools, failure modes and effects analysis (FMEA) is an effective tool in quality management. Therefore, in this study, at first, by using FMEA technique, failures in the stone industry in Iran have been identified, and the causes of each failure, and their effects and preventive and control measures of any failure are investigated. Finally, to achieve real results, the imposed costs related to any failure in the system have been calculated, and to prioritize failures instead of the use of risk priority number (RPN) is performed by using FMEA and data envelopment analysis (DEA). Somehow, the three factors of severity, occurrence, and detection of failures as inputs and cost as undesirable output are considered in this approach. The results of FMEA-DEA approach based on the cost, at Travertine and Marble processing industry, show the abilities of the proposed approach. [ABSTRACT FROM AUTHOR]

The present paper focuses on a new concept of evaluation of a performance index of hot forging dies through the combination of a process behaviour model and a reliability approach analysis of the forging process. The process behaviour is modelled and simulated using the computer-aided engineering FORGE® tool that allowed optimizing the forging parameters and determining the stresses and strains together with temperatures during the forging process and also identifying the factors affecting the die life. The respective reliability mechanical model is developed and reliability simulations have been conducted using PHIMECASoft tool in order to evaluate the reliability index β and determine the sensitivity of the variations in the random values of the input parameters of the forging process. The concept of this contribution has been applied to real industrial dies used to forge automotive steering levers produced in the forging workshop of the Ferrovial Company of Annaba in Algeria. The performance index is given by the number of forged parts corresponding to the reliability index of the dies before failure occurs. [ABSTRACT FROM AUTHOR]

Energy consumption is increasing along with the world's population and industrialization level; thus, energy and resource efficiency in manufacturing is of vital importance. In order to increase energy and resource efficiency, the amount of consumed energy must first be accurately quantified for each manufacturing process. Milling is one of the most common machining operations. In this study, a prediction model for estimating theoretical energy consumption involved in milling of prismatic parts is presented. The prediction model relies on the STEP Application Protocol 224 features for volumetric information and material properties of prismatic parts. Verification tests exemplify how engineers can utilize the presented prediction model and approach to measuring machine tool energy consumption. Test results show that the prediction model runs with 5 % accuracy. Also, effect of cutter path for prismatic milling is investigated for certain features. Furthermore, response surface methodology is utilized in order to determine optimal milling parameters of slot feature in order to minimize energy consumption when machining AISI 304 stainless steel. [ABSTRACT FROM AUTHOR]

Companies link one with another through product flow in a supply chain, so pursuing an optimal integrated production and delivery policy can help them to win from the starting line. In this research, a single-producer multi-buyer integrated model is proposed, in which the producer and all buyers work collaboratively at minimizing their total operation cost. The model is based on the equal replenishments and production cycle assumption; several aspects, as ordering cost reduction, deteriorating, backorder (buyers side), remanufacturing, and raw materials cost (producer side), are considered. The solving algorithm is established and three numerical examples are presented. An analysis is also performed to discuss the sensitivity of some important system parameters. [ABSTRACT FROM AUTHOR]

To improve the industrialization of the severe plastic deformations (SPD) technology for magnesium (Mg) alloy, a new extrusion-shear (ES) process has been explored and widely investigated owing to its potential ability to produce ultra-fine-grained microstructures in Mg alloys. It is crucial to understand the effect of die design on the deformation behavior, strain distribution, and load requirements during ES process. Three-dimensional geometric models with different channel angles (135°, 120°) in the ES dies have been designed. The plastic deformation heterogeneities of ES process with different channel angles have been analyzed from the simulation results. The results can be summarized as follows. The equivalent strains and loads during the whole ES process decrease with the increase of channel angles. The decrease of channel angle could improve the deformation inhomogeneity of ES process. Smaller channel angles could promote the higher cumulative strains and finer subgrains. The analysis results show that finer and more uniform microstructures can be obtained if channel angles in the ES dies are appropriate. It is demonstrated that the predicted results are in good agreement with experiments results and the theoretical calculations. Numerical simulations and experiments could help to understand the deformation behaviors of AZ31 Mg alloy during ES. [ABSTRACT FROM AUTHOR]

Due to industrialization and globalization, automotive sectors in both professional and societal applications have increased manufacturing and have resulted in higher production of virgin tires. These hikes in virgin tire production subsequently results in more end-of-life (EOL) tires, as well as lower quality, shorter tire lifespan, and a restricted availability of new model tires. Many developed nations have started to address EOL tire management issues through various strategies and codes of conduct, but because the environment is a global concern shared both by developed and developing nations, this study examines the issue of EOL tire management in India, a highly populated developing country. This paper proposes a framework to analyze the motivating factors of EOL tire management; it is validated in the Indian scenario with the assistance of a multi-criteria decision-making (MCDM) approach. Existing literatures are limited to the study of recycling and remanufacturing techniques. This study also provides the interrelationship between drivers and their respective influence with sound managerial implications. Finally, the paper concludes with the most influential driver of EOL tire management among all common drivers. We examine its limitations, and we shed light on the prospects of greater sustainability in EOL tire management in the future. [ABSTRACT FROM AUTHOR]

Business management involves collecting information, goods, and funds as they move from supplier to manufacturer to wholesaler to retailer to consumer. Such business comprises interconnected parts that can be fundamentally complex and dynamic. A disturbance in one subnet of the system may thus have an opposed impact on another subnets, thus disturbing the business. Disruptions can have expensive and extensive results. This research aims to improve an increased Bayesian network method to consider business disruptions. The goal is to develop strategies that can diminish the opposed impacts of the disruptions and improve overall system reliability. Two influence agents are specified: the Bayesian and junction lack influence agents. An industrial model is used to demonstrate the proposed application, making the business more reliable. Moreover, two network learning methodologies are reviewed to update the probabilities in a model. The neural network seems to be a more favorable updating tool. [ABSTRACT FROM AUTHOR]

In many industrialized countries, manufacturing industries pay stratified electricity charges depending on the time of day (i.e., peak-load, mid-load, and off-peak-load). In contrast, the emerging smart grid concept may demand that industries pay real-time hourly electricity costs so as to use energy most efficiently. This paper deals with the production and energy efficiency of the unrelated parallel machine scheduling problem. This method allows the decision maker to seek a compromise solution using the weighted sum objective of production scheduling and electricity usage. Reliability models are used to consider the energy cost aspect of the problem. This paper aims to optimize the weighted sum of two criteria: the minimization of the makespan of production and the minimization of time-dependent electricity costs. We suggest a hybrid genetic algorithm with our blank job insertion algorithm and demonstrate its performance in simulation experiments. [ABSTRACT FROM AUTHOR]

Industrialization of parallel robots requires the development of control laws that exploit their capabilities in high performance tasks. Although research in this area is increasing, theoretical results need to be experimentally tested in order to evaluate the proposed solutions. In this paper, implementation requirements of control laws in parallel robotics are discussed, and a design for implementing a real-time control and validation environment is proposed. This design provides three main advantages: (1) is focused on reducing the implementation and validation effort of control laws on prototypes, (2) is defined as an open and modular design, which allows to implement new functionalities, and (3) proposes a hardware abstraction layer which simplifies the implementation of different control laws for a given prototype. The proposed design is validated by its implementation in a five revolute joints parallel robot prototype. [ABSTRACT FROM AUTHOR]

This paper presents a cost modelling system for lean product and process development to support proactive decision making and mistake elimination at the design stage. The foundations of the system are based upon three lean product and process development enablers, namely: Set-based concurrent engineering, knowledge-based engineering, and mistake proofing (Poka-yoke). The development commenced with an industrial field study of eleven leading European industries from the aerospace, automotive, telecommunication, medical and domestic appliance sectors. Based on the requirements of industrial collaborators, the developed system comprises six modules: value identification, manufacturing process/machines selection, material selection, geometric features specification, geometric features and manufacturability assessment, and manufacturing time and cost estimation. The work involved the development of a feature-based cost estimation method for the resistance spot welding process. The developed system was finally validated using an industrial case study. The developed system has the capability to provide estimates related to product cost and associated values concurrently, facilitate decision making, eliminate mistakes during the design stage, and incorporate 'customer voice' during a critical decision making stage. [ABSTRACT FROM AUTHOR]