Abstract: In product design fields where the demand for an efficient usability is critical to its final success, it is essential to integrate user requirements into the design process from the earliest design stages. Particularly in the medical context, it is essential to systematically control the design phases in order not to neglect the strict constraints related to engineering design quality, safety, and usability requirements for the end user. Hence, in this work, an integrated user-centered product design and process simulation method is proposed. This method is aimed at enriching the state of the art in integrated product design and process simulation in the early design stages, as well as providing a novel design example of a device thought for medical contexts. The case study consists in the design of an intercom, aimed at improving patient-doctor communication in the case of bedridden patients on with helmet for Continuous Positive Airway Pressure (CPAP) therapy during COVID-19 pandemic emergency. Patients undergoing helmet-assisted ventilation are often immersed in a highly noisy environment, unable to fully communicate their needs to the doctors. Intercom devices are addressed to the doctors for improving ease communication with the patient. The proposed user-centered design for manufacturing and assembly proved to be efficient in such a complex design context.

Keywords: Integrated product and process design method | Process simulation | User-centered design

Abstract: The concept of sustainability is defined as composed of three pillars: social, environmental, and economic. Social sustainability implies a commitment to equity in terms of several “interrelated and mutually supportive” principles of a “sustainable society”; this concept includes attitude change, the Earth’s vitality and diversity conservation, and a global alliance to achieve sustainability. The social and environmental aspects of sustainability are related in the way sustainability indicators are related to “quality of life” and “ecological sustainability”. The increasing interest in green and sustainable products and production has influenced research interests regarding sustainable scheduling problems in manufacturing systems. This study is aimed both at reducing pollutant emissions and increasing production efficiency: this topic is known as Green Scheduling. Existing literature research reviews on Green Scheduling Problems have pointed out both theoretical and practical aspects of this topic. The proposed work is a critical review of the scientific literature with a three-pronged approach based on keywords, taxonomy analysis, and research mapping. Specific research questions have been proposed to highlight the benefits and related objectives of this review: to discover the most widely used methodologies for solving SPGs in manufacturing and identify interesting development models, as well as the least studied domains and algorithms. The literature was analysed in order to define a map of the main research fields on SPG, highlight mainstream SPG research, propose an efficient view of emerging research areas, propose a taxonomy of SPG by collecting multiple keywords into semantic clusters, and analyse the literature according to a semantic knowledge approach. At the same time, GSP researchers are provided with an efficient view of emerging research areas, allowing them to avoid missing key research areas and focus on emerging ones.

Keywords: dominance | persistence | scheduling | sustainable manufacturing | taxonomy

Abstract: This paper deals with the design of novel products, conceived in a complex design environment, under strict constraints and several disciplines involved in. As an application, the design of micro-bioreactors for tissue-engineering is proposed. To date, in-vitro two-dimensional (2D) culture systems have been widely used to study the mechanisms underlying cell biology. However, 3D culture systems and platforms have showed to better mimic the real tissue environment. The design of a 3D culture system of bioreactor is challenging due to several criteria derived from several disciplines, as biotechnology, engineering, and manufacturing. To this aim, a two-step integrated modular design and group multi-criteria decision-making method is proposed. In step one, a functional analysis is carried out, first, to point out the interfaces between parts and the function of each part in the assembly. Generated design alternatives have been selected by means of a group Fuzzy-TOPSIS technique, in step two. The proposed integrated design method has shown efficient in the early stages of design of novel products in complex design environments.

Keywords: Conceptual design | Fuzzy-TOPSIS | Group decision making | Micro bio reactors | Modular design

Abstract: The design of medical devices is challenging, due to strict geometry specifications and criteria belonging to several disciplines. The aim of this paper is to provide a design methodology which seems to lack in the literature of design of biomedical devices. In particular, the case study proposed in this paper concerns with the design of Bone-Biopsy (BB) needle devices. Following the design process of Pahl and Beitz, a functional analysis is carried out, to point out the interfaces between parts of existing BB needles. A morphology matrix is used to generate alternatives for the cannula holder, the core part of the product. Generated alternatives have been ranked and scored by means of the Pugh’s Controlled Convergence method according to the decision makers' opinions. In this work, the design peculiarities related to the BB needles which have been pointed out could be extended for guiding the design of other biomedical devices.

Keywords: Bone-Biopsy needle | Conceptual design | Design of biomedical devices | Multicriteria decision making | Pugh’s Controlled Convergence

Abstract: Multicrieria Decision-making methods (MCDM) are efficiently used as a support to engineering design, even if tested procedures and experience-based approaches are often preferred in SMEs and several industrial contexts. An extended critical review investigates how decision-making methods can help solving engineering design problems in automotive design. In particular, in this work, a classification of decision-making methods related to engineering design, is proposed, in which decisional techniques are matched with the design phases, and to corresponding automotive industry design problems. In literature a large amount of paper is dedicated to the selection of materials and manufacturing processes in the detail design phase. Also, hybrid methods, namely a combination of decision-making methods with other mathematical methods will be investigated to overcome some methodological drawbacks in MCDM methods. Due to the high impact of the problem in both industrial and research field, this work could help increasing production rate by reducing redesign errors related to material/processes selection problems, and concurrently transferring the knowledge of decision-making methods within the industrial context.

Keywords: Automotive design | Detail design | Material selection | Multicriteria decision making

Abstract: Sports equipment design is a young and evolving engineering discipline focused on the best simultaneous optimization of user and product as a system. In motorsports, in particular, the final performance during a race depends on many parameters related to the vehicle, circuit, weather, and tyres and the personal feelings of every single driver. Top teams in high-tech categories can invest huge amounts of money in developing simulators, but such economic commitment is not sustainable for all those teams that operate in minor but very popular categories, such as karts or mini-motorcycles. In these fields, the most common design approach is trial and error on physical prototypes. Such an approach leads to high costs, long optimization times, poor innovation, and inefficient management of the design knowledge. The present paper proposes a driver centred methodology for the design of an innovative mini racing motorcycle frame. It consists of two main phases: the drivers’ feelings translation into engineering requirements and constraints, and the exploration of the design solution space. Expected effects of the application of the proposed methodology are an overall increase in the degree of innovation, time compression, and cost reduction during the development process, with a significant impact on the competitiveness of small racing teams in minor categories.

Keywords: Design methodology | Racing motorcycle frame design | Topological optimization

Abstract: This paper presents a knowledge based engineering environment methodology to support the designer in the correct setting of geometrical and dimensional tolerances in assemblies of mechanical components. The procedure is based on the definition of the functional requirements needed to allow the proper working of the assembly; in the further, a software tool is used to do a statistical analysis of the assembly relations, providing an estimation of the components waste due to poor compliance to the tolerances. A case study given by the design of a marine power transmission is presented: the methodology leads to the change of some tolerances to improve the design by reducing the number of waste components. The strength of the methodology is represented by the fact it can help unskilled designers in the correct setting of tolerances in drawings.

Keywords: CAD | CAT | design | GD&T | power transmission

Abstract: Welding is a widely accepted process used in the assembly of aluminum chassis structures in the automotive industry. Finite element analysis (FEA) is usually adopted to predict distortions caused in the welding process. However, only nominal distortions result from FEA simulations. Welding distortions could be more accurately predicted by introducing the prediction of tolerances due to a modification of the input parameters. The aim of this work is therefore to introduce the tolerance evaluation in the FEA model, by varying the welding input parameters (geometrical and dimensional tolerances on the parts, heat input…). To find the most suitable FEA model to investigate welding process tolerance, three FEA models are compared: one is the thermo-elastic-plastic (TEP) model, and two are based on the inherent strain method. The case study uses a thin (2 mm) aluminum T-joint, which is commonly used in automotive chassis assembly. Results deriving from FEA simulations were compared with experimental data. Among the various input parameters affecting the welding process, the authors combined the dimensional tolerance on the plate thickness with the variability of the heat input. The results provided a tolerance range value for the angular distortion of the T-joint.

Keywords: automotive design | Design methods | FEA | inherent strain | Thermo-Elastic-Plastic analysis | welding Tjoint

Abstract: The use of decisional methods for the solution of engineering design problems has to be tackled on a “human” viewpoint. Hence, fundamental is the identification of design issues and needs that become a designer oriented viewpoint. Decision-based methods are systematically classified in MCDM methods, Structured Design methods and Problem Structuring methods. The results are organised in order to provide a first reference for the designer in a preliminary selection of decision-based methods. The paper shows the heterogeneous use of decision-based methods, traditionally expected to solve only some specific design problems, which have been used also in different design contexts. Moreover, several design issues, which emerged from the review process, have been pointed out and discussed accordingly. This review provided useful results for the enlargement of the state of the art on Decision Based Design methods in engineering design contexts.

Keywords: Decision Based Design methods | Engineering design. | Multi-criteria Decision Making

Abstract: The systematic integration of user needs in the product design is a key issue in industry, especially for small- and medium-sized enterprises (SMEs), which suffer a lack of engineering methods and resources. Moreover, most of the approaches described in the literature are not flexible enough to be tailored on the SMEs’ needs, involve users only in the early design phases and are not fully accessible due to the high cost in their implementation. The present paper proposes a user-centred design methodological framework specifically focused on SMEs, which supports the designer from both design and manufacturing aspects along the engineering product design process. The framework integrates engineering methods with Web-based software tools, which enable the communication and the concurrent work of the design team, and supports direct participation of users. Beside state-of-the-art methods, the framework allows the integration of specifically tailored techniques. The framework is successfully validated through an industrial case study developed in collaboration with an Italian SME. As a result, the design of an injection-moulded housing and the related interfaces of a biomedical electronic device are achieved with a reduction of uncertainty and development time, by involving users throughout the design phases and suggesting methods and tools on the basis of the designers’ know-how and SME’s specific resources.

Keywords: Decision theory | Design methodology | Product design | QFD | SMEs | User-centred design

Abstract: Decision-making methods have proven to be an effective support to engineering design. However, it is proved that very often designers prefer tested procedures and experience-based approaches. Many reasons have been discussed in the literature, dealing with consolidated design habits of people and companies, high cost in terms of time consumption, and lack of tools and knowledge. The paper systematically investigates, through an extended critical review, how decision-making methods can be used by automotive designers to solve the most common engineering problems involved along the design process. In particular, the paper proposes an original classification of the most widely used decision-making methods in engineering design, a match between such techniques with the typical design phases, and a mapping of their application into the automotive field. This research can be considered as a further step to transfer the state-of-the-art knowledge on decision-making methods to the industrial context, establishing a common background for practitioners and researchers.

Keywords: automotive industry | Decision-making methods | engineering design | industrial design | product development

Abstract: The tolerances of welded chassis are usually defined and adjusted in very expensive trials and errors on the shop floor. Computer Aided Tolerancing (CAT) tools are capable to optimize the tolerances of given product and process. However, the optimization is limited since the manufacturing process is already mostly defined by the early choices of product design. Therefore, we propose an integrated design method that considers the assembly operations before the detail design of the chassis and the concept design of the fixture system. The method consists in four phases, namely functional analysis in the CAD environment, as-sembly sequence modelling in the CAT tool, Design Of Simulation Experiment on the stack of the tolerance ranges and finally optimization of the tolerances. A case study on a car chassis demonstrates the effectiveness of the method. The method enables to selectively assign tight tolerances only on the main contributors in the stack, while generally requiring cheaper assembly operations. Moreover, a virtual fixture system is the input for the assembly equipment design as on optimized set of specifications, thus potentially reducing the number of trials and errors on the shop floor.

Keywords: 3D tolerancing | Car chassis | Computer aided tolerancing | Design op-timization | Tolerance allocation

Abstract: The enhancement of the early design stages, in the production of aeronautical engines, has been shown decisive, for developing efficient and reliable final products. Nevertheless, in most of industrial engineering design problems, the amount of design variables is large. Moreover, several nonlinearities characterize the behaviour of the physical phenomena involved and the derivatives are seldom known for all the functions. Besides, objective functions exhibit several local extremes, whereas the designer as well as the practitioner is usually interested in the global one. In this context, stochastic and evolutionary optimization have been shown capable to provide reliable solutions while keeping the computational cost at a reasonable level. Existing tools for the design and optimization of engine components deal with the optimal and detailed design of specific engine components, thus requiring several computational time and efforts to gain optimized design parameters. Hence, existing tools fit for later design phases. Conversely, this paper proposes an integrated design and optimization environment, for automatically designing optimal aeronautical piston engine configuration, still in the conceptual design stage. The optimization is performed using the MATLAB genetic algorithm (GA) toolbox®, while the automatic design of the optimized components is carried out in cascade to the optimization phase. In particular, a single-objective GA is used to evaluate the optimal dimensions of engine components related to motion, namely: crankshaft, connecting rods and screws, flywheel, propeller shaft and torsional vibration damper. For testing the efficiency of the integrated environment, the conceptual design of components of a 4-in-line Diesel aeronautical piston engine is proposed, starting from an existing similar engine. Results show a reduction of the 20 % of weight of the crankshaft in comparison to the original configuration. The proposed environment seems to be a promising tool for a fast and reliable conceptual design of piston engines for aeronautical purposes.

Keywords: Automatic design | CAD models | Conceptual design optimization | Genetic algorithm | Stochastic optimization

Abstract: Early design is crucial for the success of the final product. In the conceptual design phase, several constraints, criteria, objectives and disciplines have to be considered. To this aim, multidisciplinary optimization has proven effective for the solution of engineering design problems, even in the industrial every-day practice, to improve and simplify the work of designers in a successful quest of the best compromise solution. In this paper, a multicriteria decision-making (MCDM)-based design platform for early optimal design of industrial components is proposed. In a group decision-making context, the selection of the most suitable component among several possible layouts is performed by means of a group Fuzzy Technique for Order of Preference by Similarity to Ideal Solution approach. Hence, a multi-objective optimization is performed on the selected component by applying a multi-objective particle swarm optimization for finding optimal component dimensions. An industrial case study is presented for showing the efficiency of the multicriteria decision-making-based design platform, regarding an innovative and low-cost solution to increase the duration of heel tips in women’s shoes.

Keywords: conceptual design | design optimization | Fuzzy TOPSIS | group multicriteria decision-making | multi-objective particle swarm optimization

Abstract: Society increasingly demands for effective waste management policies to make industries more environmentally sustainable. Organizations are even issuing directives to drive choices about these policies. In particular, modern industries produce a lot of packaging, which soon become waste, even before product usage. Research can face the problem with improvements in recycling and recovery processes. However, even if recycling and recovery would enable waste to have still a value, most costs and benefits are determined at the design stage. Therefore, Design for Environment criteria must be adopted in the design tasks, from the early conceptual design when the main design solutions are defined. The design criteria to assess possible design choices must consider all the environmental impacts of packaging over its lifecycle. The present work focuses on Redesign for Environment of packaging solutions. Following a systematic design process, we use different criteria to evaluate the effects of design solutions on packaging, since waste can be seen just as one of the main phases of packaging life. To this purpose, we adopt the stages of the waste hierarchy set by the EU Waste Framework Directive 2008/98/EC as design evaluation criteria. The waste hierarchy sets a priority order for five life cycle stages that a packaging can go through. The stages of the hierarchy can be differently weighted according to the costs and benefits they involve. The proposed Design for Environment method based on the waste hierarchy criteria is finally applied in the redesign of an industrial case study. The packaging solution as foldable wooden crates were chosen for their capability to already comply with the first stages of the hierarchy, that is reducing waste with high customization to customer requirements and crate reuse. Hence, the case study improved the next stages with easing the wood recycle and recovery processes.

Keywords: Design for environment | Foldable wooden crates | Packaging | Recovery | Recycling | Waste hierarchy

Abstract: The selection of conceptual design alternatives is crucial in product development. This is due both to the fact that an iterative process is required to solve the problem and that communication among design team members should be optimized. In addition, several design constraints need to be respected. Although the literature offers several alternative selection methods, to date, only very few are currently being used in industry. A comparison of the various approaches would improve the knowledge transfer between design research and practice, helping practitioners to approach these decision support tools more effectively. This paper proposes a structured comparison of two decision support methods, namely the Fuzzy-Analytic Hierarchy Process and Pugh’s Controlled Convergence. From the literature debate regarding selection methods, four relevant criteria are identified: computational effort, suitability for the early design stages, suitability for group decision making, and ease of application. Finally a sensitivity analysis is proposed to test the robustness of each method. An industrial case study is described regarding an innovative and low-cost solution to increase the duration of heel tips in women’s shoes. The selection of conceptual design alternatives of the heel tip presents complex challenges because of the extremely difficult geometric constraints and demanding design criteria.

Keywords: Concept selection | Engineering design methods | Fuzzy-analytic hierarchy process | Pugh’s controlled convergence

Abstract: Reconfigurable manufacturing systems (RMS) are considered the future of manufacturing, being able to overcome both dedicated (DMS) and flexible manufacturing systems (FMS). In fact, they provide significant cost and time reductions in the launch of new products, and in the integration of new manufacturing processes into existing systems. The goals of RMS design are the extension of the production variety, the adaption to rapid changes in the market demand, and the minimization of the investment costs. Despite the interest of many authors, the debate on RMS is still open due to the lack of practical applications. This work is a review of the state-of-The-art on the design of cellular RMS, compared to DMS, by means of optimization. The problem addressed belongs to the NP-Hard family of combinatorial problem. The focus is on non-exact meta-heuristic and artificial intelligence methods, since these have been proven to be effective and robust in solving complex manufacturing design problems. A wide investigation on the most recurrent techniques in DMS and RMS literature is performed at first. A critical analysis over these techniques is given in the end. © 2014 Springer-Verlag London.

Keywords: Artificial intelligence | Cellular manufacturing systems | Industrial design | Meta-heuristics | Optimization | Reconfigurable manufacturing systems