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As computer-aided design (CAD) tools have become an essential aspect of modern mechanical engineering design, the demand for CAD experts has increased significantly. The development from novice, to proficient, to expert user is of particular interest to the industrial and academic design communities. Yet little is known about the development of modeling choices, strategies, and patterns that characterize expert CAD skills; much of the past work that reports user action data is based on student or novice data. We compared the CAD modeling process across nine proficient and ten expert designers as they were tested to complete the same design task. Under identical conditions-the same time constraints in the same CAD platform and with the same task-the expert users were able to complete a larger proportion of the task with higher dimensional accuracy. While the experts were able to dissect and retrieve geometries from manufacturing drawings more efficiently than proficient users, they were also able to plan a modeling strategy that required less effort and revisions. With our experimental findings, we identify the demand for procedural knowledge-building for young engineers, with the ultimate goal of more effectively developing experts in engineering design with CAD. [ABSTRACT FROM AUTHOR]

In mechanical engineering, designers have to review a designed artefact iteratively with different domain experts, e.g. from manufacturing, to avoid later changes and find a robust, optimized design. To support the designer, knowledge-based engineering offers a set of approaches and techniques that formalize and implement engineering knowledge into generic product models or decision support systems. An implementation which satisfies especially the concurrent nature of today's design processes and allow for multi-objective decision-making is multi-agent systems. Such systems consist of entities that are capable of autonomous action, interact intelligently with their environment, communicate and collaborate. In this paper, such a multi-agent system is discussed as extension for a computer-aided design software where the agents take the role of domain experts, like e.g. manufacturing technologists and make suggestions for the optimization of the design of mechanical engineering parts. A focal point is set on the collaboration concept of the single agents. Therefore, the paper proposes the use of an action-item-list as central information and knowledge sharing platform. [ABSTRACT FROM AUTHOR]

Freehand sketching is a fundamental skill in mechanical engineering and many other engineering disciplines. It not only serves as a communication tool among engineers, but plays a critical role in engineering design and problem solving. However, as computer-aided drafting has replaced traditional drawing classes nowadays, the training of students’ freehand sketching skills has been almost completely eliminated in modern engineering curricula. This paper describes the attributes of freehand sketching and its roles in several essential aspects of engineering; in particular, in its roles in problem solving, of which current literature has ignored. Representative examples are provided to show students’ freehand sketching skills in problem solving in a foundational undergraduate mechanical engineering course. Pedagogical suggestions are made on how to teach freehand sketching to engineering students. [ABSTRACT FROM AUTHOR]

Abstract: Augmented reality has been applied to develop augmented assembly systems. However, most reported studies used pre-defined assembly information; AR is predominantly used to display information and interactions between users and the augmented environment are limited. This paper presents 3D bare-hand interaction in an augmented assembly environment to manipulate and assemble virtual components. A hybrid method based on constraint analysis is presented, which interprets users’ manual assembly intents robustly without the need for auxiliary CAD information. Algorithms for assembly constraint recognition, assembly tool operations and assembly sequence evaluation have been formulated. An augmented assembly system has been developed in this research. [Copyright &y& Elsevier]

Abstract: Computer-Aided Design (CAD) applications provide design and engineering professionals with various computer-based tools to perform design activities. As efficiency is one of the most important requirements in most design tasks, in this article, we contribute a novel collaborative design approach to improving efficiency, where a complex design task can be divided and executed concurrently by multiple collaborative designers. This approach is particularly effective for design tasks where Boolean operations – widely supported by most CAD applications – are heavily used in design activities, such as architecture design, mechanical design and digital media design. We have designed and implemented a prototype system CoAutoCAD to test the approach and to demonstrate a variety of collaborative design activities. [ABSTRACT FROM AUTHOR]

This paper describes a newly created third-year CAD project in the Department of Mechanical Engineering at Bristol University which brings together the most current CAD practices and web-based technologies to provide a stimulating and dynamic learning environment for the students. The project involves the design of a machine that sorts chips of different materials. The main objective is to provide a complete and up-to date CAD experience for the students. The CAD project provides the opportunity for students to practise geometric modelling, mechanism design, assembly modelling, product visualisation (simulation and animation) and product customisation in an active learning environment. It also teaches the students parametric modelling and how quickly and efficiently to build, visualise and animate a CAD model of a proposed design, with further customisation using CAD principles. [ABSTRACT FROM AUTHOR]

Computer-aided engineering (CAE) has been successfully used in mechanical industries such as automotive industries. CAE enables us to quantitatively evaluate the mechanical performances of products and to propose an effective way to improve their performances using optimization techniques without building physical prototypes. However, CAE tools are usually utilized not at the conceptual design phase, but at the evaluation phase following the detailed design phase. This is because current CAE tools require detailed design data that does not yet exist at the conceptual design phase, and such tools also inhibit the provision of useful design suggestions that, ideally, match the way of thinking and insight of design engineers. Thus, at present, no CAE tools exist that can assist the conceptual design decision making process of design engineers. On the other hand, conceptual design processes are of great significance when seeking to create innovative and high-performance products and to shorten their development time. In order to fulfill the designer's needs during the conceptual design phase, a new type of CAE method must be constructed, one that enables concurrent design support and evaluation, and fits the way design engineers think and explore design insights. This article presents a new structural optimization method that supports concurrent decision making so that design engineers can work to obtain innovative designs and evaluate the mechanical design details of mechanical structures at the conceptual design phase. This method is developed based on the concept of product-oriented analysis and discrete, function-oriented elements, such as beam and panel elements, since these can provide design suggestions concerning the structural evaluation of reasons as to why certain design ideas obtained are reasonable or optimal in the design sense. The basic ideas and specifications needed to construct the method are explained and the construction of the structural optimization design method is discussed. The optimization algorithm is developed using the ground structure approach and CONLIN sequential convex programming. The examples provided demonstrate the utility of the proposed methodology for supporting design engineers' concurrent decision making, so that innovative mechanical designs can be evaluated at the conceptual design phase. [ABSTRACT FROM AUTHOR]

This paper details the progress toward the development of the ideal mechanical engineering design support system. It attempts to look at the gap between the needs of a mechanical engineer and what is currently available on CAD systems. Since the term CAD emphasizes that the computer is an aid to the human designer, this paper is designer-centric. It is based heavily on the activities performed by designers and the types of information developed by them. Seventeen goals for the ideal mechanical design support system are listed. These are directed at the types of information developed during the design process and the activities used to develop them. For each of the seventeen, background information, the current state-of-the-art, and opportunities for future development are itemized. [ABSTRACT FROM AUTHOR]