Reliability Evaluation of Manufacturing Systems: Methods and Applications

The measurement and optimization of the efficiency level of a manufacturing system, and in general of a complex systems, is a very critical challenge, due to technical difficulties and to the significant impact towards the economic performance. Production costs, maintenance costs, spare parts management costs force companies to analyse in a systematic and effective manner the performance of their manufacturing systems in term of availability and reliability (Manzini et al. 2004, 2006, 2008). The reliability analysis of the critical components is the basic way to establish first and to improve after the efficiency of complex systems. A number of methods (i.e. Direct Method, Rank Method, Product Limit Estimator, Maximum likelihood Estimation, and others (Manzini et. Al., 2009) all with reference to RAMS (Reliability, Availability, Maintainability and Safety) analysis, have been developed, and can bring a significant contribution to the performance improvement of both industrial and non-industrial complex systems. Literature includes a huge number of interesting methods, linked for example to preventive maintenance models; these models can determine the best frequency of maintenance actions, or the optimization of spare parts consumption or the best management of their operating costs (Regattieri et al., 2005, Manzini et al., 2009). Several studies (Ascher et al..1984, Battini et al., 2009, Louit et al., 2007, Persona et al. 2007) state that often these complex methodologies are applied using false assumptions such as constant failure rates, statistical independence among components, renewal processes and others. This common approach results in poor evaluations of the real reliability performance of components. All subsequent analysis may be compromised by an incorrect initial assessment relating to the failure process. A correct definition of the model describing the failure mode is a very critical issue and requires efforts which are often not sufficiently focused on. In this chapter the author discusses the model selection failure process, from the fundamental initial data collection phase to the consistent methodologies used to estimate the reliability of components, also considering censored data. This chapter introduces the basic analytical models and the statistical methods used to analyze the reliability of systems that constitute the basis for evaluation and prediction of the stochastic failure and repair behavior of complex manufacturing systems, assembled using a variety of components. Consequently, the first part of the chapter presents a general framework for components which describes the procedure for the solution of the complete Failure Process Modeling (FPM) problem, from data collection to final failure modeling, that, in particular, develops the fitting analysis in the renewal process and the contribution of censored data throughout the whole process. The chapter discusses the main methods provided in the proposed framework. Applications, strictly derived from industrial case studies, are presented to show the capability and the usefulness of the framework and methods proposed

Manufacturing Logistics and Packaging Management Using RFID

none2The chapter is centred on the analysis of internal flow traceability of goods (products and/or packaging) along the supply chain by an Indoor Positioning System (IPS) based on Radio Frequency IDentification (RFID) technology. A typical supply chain is an end-to-end process with the main purpose of production, transportation, and distribution of products. It is relative to the products’ movements from the supplier to the manufacturer, distributor, retailer and finally to the end consumer. Moreover, a supply chain is a complex amalgam of parties that require coordination, collaboration, and information exchange among them to increase productivity and efficiency [1, 2]. A supply chain is made up of people, activities, and resources involved in moving products from suppliers to customers and information from customers to suppliers. For this reason, the traceability of logistics flows (physical and information) is a very important issue for the definition and design of manufacturing processes, improvement of layout and increase of security in work areas. European Parliament (Regulation (EC) No. 178/2002) [3] makes it compulsory to trace goods and record all steps, used materials, manufacturing processes, etc. during the entire life cycle of a product [4]. According to the European Parliament, companies recognize the need and importance of tracing materials in indoor environments. Traditionally, the traceability system is performed through the asynchronous fulfilment of checkpoints (i.e. doorways) by materials. In such cases, the tracking is manual, executed by operators. Often companies are not aware of the inefficiencies due to these systems of traceability such as low precision and accuracy in measurements (i.e. no information between doorways), more time spent by operators and costs (due to the full-effort of operators who have to trace target positions and movements). According to [5] every day millions of transport units (cases, boxes, pallets, and containers) are managed worldwide with limited or even with lack of knowledge regarding their status in real-time. In order to overcome the lack of data due to traceability, automatic identification procedures (Auto-ID) could be a solution. They have become very popular in many service industries, purchasing and distribution logistics, manufacturing companies and material flow systems. Automatic identification procedures provide information about people, vehicles, goods, and products in transit within the company [6]. It is possible to note several advantages using an automatic identification system such as the reduction of theft, increase of security during the transport and distribution of assets, and increase of knowledge of objects’ position in real-time. Automatic identification procedures can also be applied to packaging products, instead of to each item contained in the package. Packaging is becoming the cornerstone of processing activities [7]. Sometimes products are very expensive and packages contain important and critical goods (for example dangerous or explosive materials) and the tracking of goods – and packaging in particular – is a critical function. The main advantage of automatic system application to packages is the possibility to map the path of all items contained into the packages and to find out their real-time position. The installation of automatic systems in packages allows costs and time to be reduced (by installing, for example, the tag directly on the package instead of on each product contained inside the package). The purpose of the chapter is to provide an innovative automatic solution for the traceability of everything that moves within a company, in order to simplify and improve the process of logistics flow traceability and logistics optimization. The chapter deals with experimental research that consists of several tests, static and dynamic, tracing the position (static) and movements (dynamic) of targets (e.g. people, vehicles, objects) in indoor environments. In order to identify the best system to use in the real-time traceability of products, the authors have chosen Real Time Location Systems (RTLSs) and, in particular, the Indoor Positioning Systems (IPSs) based on Radio Frequency IDentification (RFID) technology. The authors discuss the RFID based system using UWB technology, both in terms of design of the system and real applications. The chapter is organized as follows: Section 2 briefly describes IPS systems, looking in more depth at RFID technology. After that the experimental research with the relative results and discussion are described in Section 3. Section 4 presents an analysis of RFID traceability systems applied to packaging. Conclusions and further research are discussed in Section 5.mixedREGATTIERI A.; SANTARELLI GREGATTIERI A.; SANTARELLI

The Important Role of Packaging in Operations Management

The chapter focuses on the analysis of the impact of packaging in Operations Management (OM) along the whole supply chain. The product packaging system (i.e. primary, secondary and tertiary packages and accessories) is highly relevant in the supply chain and its importance is growing because of the necessity to minimize costs, reduce the environmental impact and also due to the development of web operations (i.e. electronic commerce). A typical supply chain is an end-to-end process with the main purpose of production, transportation, and distribution of products. It is relative to the products\u2019 movements normally from the supplier to the manufacturer, distributor, retailer and finally the end consumer. All products moved are contained in packages and for this reason the analysis of the physical logistics flows and the role of packaging is a very important issue for the definition and design of manufacturing processes, improvement of layout and increase in companies\u2019 efficiency. In recent years, companies have started to consider packaging as a critical issue. It is necessary to analyse the packages\u2019 characteristics (e.g. shape, materials, transport, etc.) in order to improve the performance of companies and minimize their costs. Packaging concerns all activities of a company: from the purchasing of raw materials to the production and sale of finished products, and during transport and distribution. In order to manage the activities directly linked with the manufacturing of products (and consequently with the packaging system), the OM discipline is defined. It is responsible for collecting various inputs and converting them into desired outputs through operations [1]. Recently, more and more companies have started to use web operations. Electronic commerce (e-commerce) is the most promising application of information technology witnessedin recent years. It is revolutionising supply chain management and has enormous potential for manufacturing, retail and service operations. The role of packaging changes with the increase in the use of e-commerce: from the traditional \u201cshop window\u201d it has become a means of information and containment of products. The purpose of the chapter is to briefly describe a model of OM discipline usable to highlight the role of packaging along the supply chain, describing different implications of an efficient product packaging system for successful management of operations. Particular attention is paid to the role of product packaging in modern web operations. The chapter is organised as follows: Section 2 presents a brief description of OM in order to engage the topic of packaging. The packaging logistics system is described in Section 3, before presenting experimental results of studies dealing with packaging perception by both companies and customers [2; 3]. Moreover, Section 3 introduces the packaging logistics system also including the analysis of the role of packaging in OM and a description of a complete mathematical model for the evaluation of total packaging cost is presented. Section 4 presents background about modern e-commerce and its relationship with OM. Packaging and e-commerce connected with OM is described in Section 5 and a case study on packaging e-commerce in operations is analysed in Section 6. Finally, the conclusion and further research are presented

Reliability Assessment of a Packaging Automatic Machine by Accelerated Life Testing Approach

Industrial competitiveness in innovation, the time of the market introduction of new machines and the level of reliability requested implies that the strategies for the development of products must be more and more efficient. In particular, researchers and practitioners are looking for methods to evaluate the reliability, as cheap as possible, knowing that systems are more and more reliable. This paper presents a reliability assessment procedure applied to a mechanical component of an automatic machine for packaging using the accelerated test approach. The general log-linear (GLL) model is combined based on a relationship between a number strains, in particular mechanical and time based. The complete Accelerated Life Testing - ALT approach is presented by using Weibull distribution and Maximum Likelihood verifying method. A test plan is proposed to estimate the unknown parameters of accelerated life models. Using the proposed ALT model, the reliability function of the component is evaluated and then compared with data from the field collected by customers referring to 8 years of real work on a fleet of automatic packaging machines. The results confirm that the assessment method through ALT is effective for lifetime prediction with shorter test times, and for the same reason it can improve the design process of automatic packaging machines

A Supporting Decisions Platform for the Design and Optimization of a Storage Industrial System

Warehouses are one of the most critical resources in production systems, whose performance significantly depend on the availability of materials in the right location, in the right quantity and at the right time. Literature presents many contributions for the design and control of a storage system, but a few of them discuss on the importance of an integrated approach based on the adoption of different supporting decisions models and tools, from mixed integer linear programming (MILP) to visual interactive simulation (VIS), passing through heuristic procedures and cluster analysis (CA). This chapter presents a conceptual and integrated framework for the design, management, control and optimization of both manual, i.e. man-on-board, picker to part and automated, i.e. part to picker, storage systems, both unit-load and less than unit-load order picking systems (OPS), by the development and application of different models and tools. The proposed framework integrates the management decisions in order to find not a system configuration as a result of local optima, but the minimal cost warehousing system as a result of the following integrated decisions: the space allocation to the forward area and the bulk area in a OPS, the system layout, the storage allocation within each area, i.e. the determination of the storage level devoted to a stock keeping unit (sku) both in fast pick area and in reserve area, the storage locations assignment, i.e. the determination of the warehousing system location to be assigned to a sku, the routing policies, the operating procedures, etc. A discussion on supporting decisions models and tools useful for practitioners of industry to face these critical problems is presented and finally a case study illustrated

Automatic assessment of the ergonomic risk for manual manufacturing and assembly activities through optical motion capture technology

Abstract Safeguard the operator health is nowadays a hot topic for most of the companies whose production process relies on manual manufacturing and assembly activities. European legislations, national regulations and international standards force the companies to assess the risk of musculoskeletal disorders of operators while they are performing manual tasks. Furthermore, international corporates typically require their partners to adopt and implement particular indices and procedures to assess the ergonomic risks specific of their industrial sector. The expertise and time required by the ergonomic assessment activity compels the companies to huge financial, human and technological investments. An original Motion Analysis System (MAS) is developed to facilitate the evaluation of most of the ergonomic indices traditionally adopted by manufacturing firms. The MAS exploits a network of marker-less depth cameras to track and record the operator movements and postures during the performed tasks. The big volume of data provided by this motion capture technology is employed by the MAS to automatically and quantitatively assesses the risk of musculoskeletal disorders over the entire task duration and for each body part. The developed hardware/software architecture is tested and validated with a real industrial case study of a car manufacturer which adopts the European Assembly Worksheet (EAWS) to assess the ergonomic risk of its assembly line operators. The results suggest how the MAS is a powerful architecture compared to other motion capture solutions. Indeed, this technology accurately assesses the operator movements and his joint absolute position in the assembly station 3D layout. Finally, the MAS automatically and quantitatively fill out the different EAWS sections, traditionally evaluated through time- and resource-consuming activities

prognostic health management of production systems new proposed approach and experimental evidences

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Corrigendum: Corrigendum to 'Learning manual assembly through real-time motion capture for operator training with augmented reality"

Abstract The authors regret that The authors would like to apologise for any inconvenience caused