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The purpose of this exploratory paper is to analyze how complexity of an artifact affects designing processes of its mechanical, electric, and software sub‐systems.

Based on existing empirical research and frameworks of axiomatic design, product architecture, and product development process, the paper proposes a simple model of functional and structural design to examine how engineers' ways of thinking differ among mechanical, electric and software engineers.

This paper argues that products and artifacts tend to become complex (often with integral architecture) when customers' functional requirements become more demanding and societal/technological constraints become stricter, and that complex mechanical products are often accompanied by electronic control units with complex functions. This implies that designing complex mechanical products often requires intensive coordination among mechanical, electric and software engineers. This, however, is not easy, as engineers' way of thinking is often different among the three areas: mechanical engineers want to complete structural design information first to build prototypes; electrical and software engineers (the latter in particular) request complete functional information first.

In order to solve the above‐mentioned mechanical‐electrical‐software coordination problem, engineers need to share basic design concept of the product in question. Heavy‐weight product managers who infuse the product concept to the project members might be the key to this coordination. Companies may need to make sure that their product development processes are friendly to all of the three groups of engineers.

Although designing complex artifacts has been a popular research theme since H. Simon's seminal work, issues of organizational coordination for developing complex products, with increasing managerial importance, need further research. With an empirical case of the automobile and electronic products, the present paper is unique in that it combines frameworks of product development processes, product architectures, and organizational capabilities.

Actuators for human-interactive robot systems require transparency and guaranteed safety. An actuation system is called transparent when it is able to generate an actuation force as desired without any actuator dynamics. The requirements for the transparent actuation include high precision and large frequency bandwidth in actuation force generation, zero mechanical impedance and so on. In this paper, a compact rotary series elastic actuator (cRSEA) is designed considering the actuation transparency and the mechanical safety.

The mechanical parameters of a cRSEA are optimally selected for the controllability, the input and output torque transmissibility and the mechanical impedance by simulation study. A mechanical clutch that automatically disengages the transmission is devised such that the human is mechanically protected from an excessive actuation torque due to any possible controller malfunction or any external impact from a collision. The proposed cRSEA with a mechanical clutch is applied to develop a wearable robot for incomplete paraplegic patients. To verify torque tracking performance and disengagement of the mechanical clutch, experiments were conducted.

As the effects of the gear ratio, N1, on the four control performance indexes are conflicting, it should be carefully selected such that the controllability and the output torque transmissibility are maximized, while the disturbance torque transmissibility and the mechanical impedance are minimized. When the four control performance indexes were equally weighted, N1 was selected as 30. Experimental results showed that the designed cRSEA provided good control performances and the mechanical clutch worked properly.

It is important to design the actuator so as to maximize the control performance in accordance with its purpose. This paper presents the design guidelines for the SEA by introducing four control performance indexes and analyzing how the performance indexes vary according to the change of design parameter. From the viewpoint of practicality, a mechanical clutch design method that prevents excessive torque from being transmitted to the wearer and an analysis to solve the locking phenomenon when using a worm gear are presented, and a design method of SEA satisfying both control performance and practicality is presented.

The generic design environment for a flexible printed‐circuit board assemblies (PCBA) remanufacturing cell contains four interrelated complex design domains. Mechanical design domains are really complex and the use of well‐proven mechanical product design methodologies does not help the designer. Hence, this paper aims to develop a generic systematic design methodology for a flexible PCBA remanufacturing cell.

The study investigates the use of conventional mechanical product design techniques for the design of a flexible PCBA rework (remanufacturing) cell. It indicates problems and the weaknesses when conventional product design techniques are used for the development of flexible manufacturing systems (FMS). It then provides a new systematic mechanical design methodology for designing a flexible PCBA rework (remanufacturing) cell. The design methodology is intended to be generic in order to apply successfully to any FMS design.

Conventional product design methodology cannot be used directly for the design of a flexible PCBA remanufacturing cell. Hence, two design methodologies were developed: the generic FMS mechanical design methodology and a specific FMS design methodology for a PCBA rework cell. The first one was developed based on the tasks of the conventional product design process integrated with new design tools. The generic design methodology was then extended to obtain the second methodology for a PCBA rework cell design. Both of the methodologies were applied to a flexible PCBA rework cell design problem. Both design methodologies eliminated unusable design solutions at the early design stages of the conceptual design process and made the design process easier.

The generic and specific design methodologies provide a better design environment, even for less specialized FMS designers.

The design methodologies may help for the commercialization of a flexible PCBA remanufacturing cell that may be used for SM rework and assembly.

This paper investigates how designers exploit the full potential of additive manufacturing (AM). AM yields a broad range of advantageous properties including the possibility to fabricate mechanical multi-body structures.

This case study explores the possibilities and limitations in designing mechanical multi-body structures for AM, focused on the development of a selective laser sintering (SLS) version of Theo Jansen’s “Strandbeest” walking mechanism, dubbed Animaris Geneticus Parvus (AGP). We discuss the design process and considerations involved and attempt to distill design guidelines.

Novel structural solutions were developed to enable SLS fabrication of the AGP, specifically cross-shaped pivot pins, increased clearance between bodies, spacing studs, restricting axial play with pins, partial disassemblies and increased clearance around extremities. The result is a functioning walking mechanism of 74 components can be fabricated at once without human intervention.

This article represents a case study; although it does mention adapted design rules for SLS, its greatest contribution is the holistic approach – to integrate a number of engineering challenges in one prototypical manifestation.

Part consolidation by AM could bring great benefits in future product design applications. The findings show that complex multi-body mechanical structures with more than 70 elements are feasible by AM without assembly. This presents new business opportunities for AM service bureaus and novel product opportunities for designers.

As a case study, this article provides inspiration of the mechanical complexity beyond regular products – from original idea to end result. For researchers, key contribution is the approach in obtaining design optimization strategies which provides engineering designers with a new language to consider SLS.

In 2004, the Council for Higher Education (CHE) required a curriculum responsiveness to the teaching and learning of literacies at the programme level, which needed to be addressed across all disciplines. This study aims to describe a situated higher education (HE) collaboration project between mechanical engineering and the Department of Applied Language Studies (DALS) at Nelson Mandela University from 2010 to 2014. The collaboration project aimed to develop the literacies levels of engineering students, reduce the first-year attrition rate and prepare engineering students to meet the high graduate attribute expectations of a competitive workplace amid employer concerns that engineering graduate communication competencies were lacking and insufficient.

The collaboration study used a mixed-method approach, which included student and lecturer questionnaires, as well as an interview with one engineering lecturer to determine his perceptions of the collaboration practices instituted. As the sample was purposeful, two mechanical engineer lecturers and 32 second-year mechanical engineering students from 2012 to 2013 were selected as the study’s participants, as they met the study’s specific needs. From the questionnaire responses and transcribed interview data, codes were identified to describe the themes that emerged, namely, rating the collaboration practices, attitudes to the course, report feedback provided and report template use.

Most of the student participants viewed the collaboration practices positively and identified their attitude as “positive” and “enthusiastic” to the language/engineering report collaboration initiative. The report feedback practices were viewed as improving writing skills and enabling the students to relate report writing practices to workplace needs. The engineering lecturers also found that the collaboration practices were enabling and improved literacy levels, although time was identified as a constraint. During the four-year collaboration period, the language practitioner increasingly gained report content knowledge, as well as unpacking the specific rhetorical structures required to produce the report text by co-constructing knowledge with the mechanical engineering lecturers.

Studies have shown that language practitioners and discipline lecturers need to change their conceptualisation of academic discourses as generic transferable skills and autonomous bodies of knowledge. Little benefit is derived from this model, least of all for the students who grapple with disciplinary forms of writing and the highly technical language of engineering. Discipline experts often tend to conflate understandings of language, literacy and discourse, which lead to simplistic understandings of how students may be inducted into engineering discourses. Therefore, spaces to nurture and extend language practitioner and discipline-expert collaborations are needed to embed the teaching and learning of discipline-specific literacies within disciplines.

For the collaboration project, the language practitioner and mechanical engineering lecturers focused their collaboration on discussing and negotiating the rhetorical and content requirements of the Design 3 report as a genre. To achieve the goal of making tacit knowledge and discourse explicit, takes time and effort, so without the investment of time and buy-in, interaction would not be sustained, and the collaboration would have been unproductive. As a result, the collaboration project required regular meetings, class visits and negotiations, as well as a language of description so that the often tacit report discourse conventions and requirements could be mutually understood and pedagogically overt to produce “legitimate texts” (Luckett, 2012 p. 19).

In practice, peer collaboration is often a messy, complex and lengthy process, which requires systematic and sustained spaces to provide discourse scaffolding so that the criteria for producing legitimate design reports are not opaque, but transparent and explicit pedagogically. The study also describes the organisational circumstances that generated the collaboration, as establishing and sustaining a collaborative culture over time requires planning, on-going dialogic spaces, as well as support and buy-in at various institutional levels to maintain the feasibility of the collaboration practice.

Literacy and discourse collaboration tends to reduce role differentiation amongst language teachers and specialists, which results in shared expertise for problem-solving that could provide multiple solutions to literacy and discourse learning issues. This finding is important, especially as most studies focus on collaboration practices in isolation, whilst fewer studies have focused on the process of collaboration between language practitioners and disciplinary specialists as has been described in this study.

THE fact that the mechanical design engineer requires special treatment is well known to most engineering managers. Within the typical engineering department, the mechanical design engineers will generally own the distinction of being the most temperamental, the most self‐centred, the most introverted, the most fractious, the most lacking in team spirit, the most productive, the most dedicated, and the hardest to replace members of the organization.

The purpose of this study was to bring a new structural hybrid design approach to improve the mechanical and biological properties of the bone scaffolds fabricated by laser powder bed fusion, selective laser melting (SLM).

In designing the hybrid scaffolds, different unit cells were used such as dodecahedron (DCH), grid (G), octet-truss (OCT) with partially dense (PDsl) and fully dense (FDsl) surface layers. After fabrication of scaffolds on SLM machine, compression test and cell viability test were applied to observe the effect of hybrid design on mechanical and biological properties of the scaffolds.

It has been observed that designing the scaffold with partially dense or FDsl surfaces did not have a critical effect on the cell viability. On the contrary, the compression strength of scaffold increased from 56  to 100 MPa when the surface layer of the scaffold was designed as FDsl surface instead of partially dense surface. It has also been observed that the scaffold having the highest hybridity (PDsl+G+DCH+OCT) delivered the highest cell viability performance and had a compressive strength slightly higher than that of the scaffolds with single unit cell, PDsl+OCT.

This study brings a new approach to designing femur bone scaffold for fabricating with SLM. This hybrid design approach, including different unit cells in a single scaffold, covers many requirements of femur bone in terms of mechanical and biological properties.

The purpose of this paper is to evaluate how the direct access to additive manufacturing (AM) systems impacts on education of future mechanical engineers, within a Master’s program at a top Italian University.

A survey is specifically designed to assess the relevance of entry-level AM within the learning environment, as a tool for project development. The survey is distributed anonymously to three consecutive cohorts of students who attended the course of “computer-aided production (CAP)”, within the Master of Science Degree in Mechanical Engineering at Politecnico di Torino. The course includes a practical project, consisting in the design of a polymeric product with multiple components and ending with the production of an assembled prototype. The working assembly is fabricated by the students themselves, who operate a fused deposition modelling (FDM) machine, finish the parts and evaluate assemblability and functionality. The post-course survey covers diverse aspects of the learning process, such as: motivation, knowledge acquisition, new abilities and team-working skills. Responses are analyzed to evaluate students’ perception of the usefulness of additive technologies in learning product design and development. Among the projects, one representative case study is selected and discussed.

Results of the research affirm a positive relationship of access to AM devices to perceived interest, motivation and ease of learning of mechanical engineering. Entry-level additive technologies offer a hands-on experience within academia, fostering the acquisition of technical knowledge.

The survey is distributed to more than 200 students to cover the full population of the CAP course over three academic years. The year the students participated in the CAP course is not tracked because the instructor was the same and there were no administrative differences. For this reason, the survey administration might be a limitation of the current study. In addition to this, no gender distinction is made because historically, the percentage of female students in Mechanical Engineering courses is about 10 per cent or lower. Although the answers to the survey are anonymous, only 37 per cent of the students gave a feedback. Thus, on the one hand, impact assessment is limited to a sample of about one-third of the complete population, but, on the other hand, the anonymity ensures randomization in the sample selection.

Early exposure of forthcoming designers to AM tools can turn into a “think-additive” approach to product design, that is a groundbreaking conception of geometries and product functionalities, leading to the full exploitation of the possibilities offered by additive technologies.

Shared knowledge can act as a springboard for mass adoption of AM processes.

The advantages of adopting AM technologies at different levels of education, for diverse educational purposes and disciplines, are well assessed in the literature. The innovative aspect of this paper is that the impact of AM is evaluated through a feedback coming directly from mechanical engineering students.

The purpose of this paper is to find a method for key assembly structure identification in complex mechanical assembly. Three-dimensional model reuse plays an increasingly important role in complex product design and innovative design. Assembly model has become important resource of models reuse in enterprises, which contains certain function assembly structures. These assembly structures implicating plenty of design intent and design experience knowledge can be used to support function-structure design, modular design reuse and semantics analysis for complex product.

A method for identifying key assembly structures in assembly model is presented from the viewpoint of assembly topology and multi-source attributes. First, assembly model is represented based on complex network. Then, a two-level evaluation model is put forward to evaluate importance of parts assembled, and the key function parts in assembly can be obtained. After that, on the basis of the function parts, a heuristic algorithm upon breadth first searching is given to identify key assembly structures.

The method could be used to evaluate key function parts and identify key assembly structures in complex mechanical assembly according to the specific circumstances.

The method can not only help designers find the key assembly structure in complex mechanical assembly model, facilitate the function-structure designing and semantics analyzing, and thereby improve the efficiency of product knowledge reuse, but also assist in analyzing influence scope of key function part changing and optimization of the assembly process for complex mechanical assembly.

The paper is the first to propose a method for key assembly structure identification in complex mechanical assembly, where the key function parts can be evaluated through a two-level evaluation model, and the key assembly structures are identified automatically based on complex network.

The purpose of this paper is to present a new efficient method for the tolerance–reliability analysis and quality control of complex nonlinear assemblies where explicit assembly functions are difficult or impossible to extract based on Bayesian modeling.

In the proposed method, first, tolerances are modelled as the random uncertain variables. Then, based on the assembly data, the explicit assembly function can be expressed by the Bayesian model in terms of manufacturing and assembly tolerances. According to the obtained assembly tolerance, reliability of the mechanical assembly to meet the assembly requirement can be estimated by a proper first-order reliability method.

The Bayesian modeling leads to an appropriate assembly function for the tolerance and reliability analysis of mechanical assemblies for assessment of the assembly quality, by evaluation of the assembly requirement(s) at the key characteristics in the assembly process. The efficiency of the proposed method by considering a case study has been illustrated and validated by comparison to Monte Carlo simulations.

The method is practically easy to be automated for use within CAD/CAM software for the assembly quality control in industrial applications.

Bayesian modeling for tolerance–reliability analysis of mechanical assemblies, which has not been previously considered in the literature, is a potentially interesting concept that can be extended to other corresponding fields of the tolerance design and the quality control.