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Due to highly competitive markets, constantly shifting consumer requirements, and technological advances, product families are continuously evolving over time. This product evolution leads to new part variants being added to the existing part mix. When at a future time the manufacturing system is not capable, as is or in a reconFigured state, to manufacture the evolved part variants, then this has negative consequences on business performance. This phenomena is being termed as disruptive product evolution. Due to complex interdependencies, incomplete information and uncertainty in manufacturing requirements this phenomena leads to a wicked problem. In order to tame such a wicked problem, this paper contributes and evaluates a knowledge-based decision-making approach that supports manufacturing system designers in exploring the interplay between business strategy, evolving product range and manufacturing systems. A prototype digital factory tool based on this approach has been developed and evaluated. The encouraging results obtained have shown that this research paves the way for the development and integration of such knowledge-based decision-making approaches within state of the art digital factory tools.

Changing production systems and product requirements can trace their origin in volatile customer behaviour and evolving product requirements. This dynamic nature of customer requirements has been described as a constantly moving target, thus presenting a significant challenge for several aspects of product development. To deal with this constant and sometimes unpredictable product evolution, cyber physical production systems (CPPS) that employ condition monitoring, self-awareness and reconfigurability principles, have to be designed and implemented. This research contributes a CPPS design approach that proactively provides the required CPPS design knowledge. This approach aims to minimise or avoids future consequences and disruptions on the CPPS. This knowledge needs to be provided at the right time whilst not being intrusive to the production system designer's cognitive activity. To effectively deal with the complexity of the cyber physical production system design activity with a manual method would lead to a time consuming, and complex support tool which is hard to implement, and difficult to use. The CPPS design approach has therefore been implemented in a prototype digital factory tool. This paper describes in detail the system requirements and system architecture for this tool. In order to establish the effectiveness of the proposed approach for designing cyber physical production systems, the prototype digital factory tool has been evaluated with a case study and a number of semi-structured interviews with both industrial and scientific stakeholders. The encouraging results obtained from this research evaluation have shown that such an approach for supporting the CPPS design activity makes stakeholders aware of their decision consequences and is useful in practice. This result can lead the way for the development and integration of such knowledge-based decision-making approaches within state-of-the-art digital factory and Computer Aided Engineering Design (CAED) tools.

Manufacturing system design is a complex and demanding activity and the system designer has to take many factors into consideration during the development process including the demand and technological requirements of the products or product families. Central to this activity is the synthesis decision making process, during which the designer defines the elements that will make up the manufacturing system. This research identifies in the decision making process a critical activity and contributes a phenomena that can be used by a framework to support designers to address complex issues such as changeability and the evolution of products over the manufacturing system life-cycle., This research work was partially funded through an ERDF Project (Project No. ERDF083). The first and second authors would therefore like to thank the Malta Council for Science and Technology (MCST) who is administering this project., peer-reviewed

Increasing market pressure is forcing manufacturing companies to improve product lead times and quality at reduced cost. An important approach aimed at tackling these problems is to generate manufacturing/assembly system models concurrently with the design solutions of a component. A designer can therefore make product design decisions while having access to, and interacting with, the evolving ‘virtual’ manufacturing system models. This allows designers to foresee any potential manufacturing problems caused by design decisions. This paper presents an approach that proactively supports designers in making informed design decisions, through the timely revelation of knowledge about manufacturing and assembly processes. Such knowledge, when provided early in the design process, allows designers to avoid negative implications and to use positive ones. Based on this approach, a knowledge-intensive computer aided design (KICAD) prototype tool, named FORESEE, has been developed. FORESEE is a proof-of-concept system and allows designers to foresee and explore manufacturing and assembly consequences caused by design decisions, as the design of a mechanical component evolves. The paper presents an outline of the KICAD approach, together with a brief description of FORESEE's architecture and implementation. The application of FORESEE is demonstrated through a thermoplastic component design case study. FORESEE has been evaluated by practising designers. Evaluation results indicate that the approach has the potential proactively to support component design.

This paper describes a generic approach to guiding designers when making decisions during the early stages of design. The objective of the research is to enable designers to foresee unintended life-cycle consequences during mechanical component design. Engineering design is a process of evolving solutions to a design problem through the commitment of decisions. As a designer commits a new design decision, a more concrete design solution is generated. Decisions made can have intended and unintended consequences on the performance of the life phase activities that follow, such as manufacturing, assembly, and disposal. Many existing tools only consider the impact of the design solution on later life-cycle phases when the solution is almost complete. This makes changes expensive and difficult. This paper presents a novel approach to how consequences encountered in down stream life-cycle phases can be brought to the designer's attention early in generation of component form. For this purpose, a knowledge model has been derived from a phenomena model. The phenomena model describes how life-cycle consequences are generated during component synthesis. An insight into the representation of the resultant knowledge model is discussed through examples. The implementation of a prototype Knowledge Intensive CAD tool, entitled FORESEE, aimed at supporting life-oriented, feature-based component synthesis and exploration, is also described. The results of the evaluation of FORESEE with a range of designers show that by using the system designers are motivated to explore alternative design solutions and are able to make more informed design decisions. This highlights that the knowledge structure provides a base for extending feature-based component design to a ‘Design Synthesis for Multi-X’ approach.

This paper deals with the development of a computational framework that aims to facilitate innovative endeavours during product development. A problem analysis carried out revealed that both stakeholder collaboration and artefact simulation are considered important for supporting innovation, the first through the availability of more ideas and the latter for analysing the feasibility of these ideas prior to their implementation in practice. However, it was observed that the use of collaboration tools and simulation tools is still lacking in practice mainly due to lack of awareness or perceived lack of necessity. This research thus aims to develop a framework that helps support innovation in product development through the use of these tools. From the preliminary evaluation of the solution developed, it was found that the portal and its underlying framework are indeed useful for supporting innovation.

The main problem addressed in this paper concerns the lack of computational tools that allow designers to automatically extract three-dimensional (3D) shape models from paper-based form sketches during early design. To address this problem, various Computer-Aided Sketching (CAS) tools have been developed. However, their digital sketching medium replaces the natural, portable and readily available paper. To address these issues, this paper reports the development of a framework, which allows designers to obtain 3D virtual models and related life-cycle knowledge directly from early form paper-based sketches. The evaluation results of the implemented prototype tool, X-SKetch, provide a degree of evidence that this framework is a step towards making 3D geometric modelling software and computer technology available not only to designers but also to other users.

Increasing competition requires more and more effort in delivering new products with better prices, good quality and environment savings. In this scenario, since most of the cost and product characteristics are dependent on commitments taken at the early design stages, designers require tools supporting them at considering the consequences of their decisions on the whole product life-cycle, starting from the conceptual design stage to the disposal phase. The adoption of such tools may enforce the exploration of different alternatives thus increasing the possibility of identifying the most convenient and innovative solution. Form features have been recognized as shape-oriented elements for associating geometry with engineering meaning, thus helping in reasoning on products in functional terms. However as argued in this paper, information on shape alone is insufficient for meaningful evaluation and forecast of life-cycle product consequences. The paper presents an approach for considering ‘life-cycle consequences’ during the design decision process, by taking into account both artefact features and the characteristics of the involved life-cycle systems.

Designers are now expected to ‘generate’ life-oriented design solutions. This transition to ‘Design Synthesis for Multi-X (DFΣX)’ reflects an increase in demands being put on designers. This paper reports on the development and implementation of a Knowledge Intensive CAD (KICAD) tool aimed at proactively supporting designers in foreseeing and exploring multiple life-cycle consequences co-evolving during mechanical artefact design decision making. A phenomena model describing ‘how’ consequences are generated highlights the necessity of designers engaging in concurrent synthesis. This understanding is exploited by a ‘Knowledge of Consequences’ approach to DFΣX on which the KICAD implementation is based. The paper includes an outline of the KICAD’s knowledge model, system requirements and architecture. The application of a prototype named FORESEE to pro-actively supporting ‘life-oriented’ exploration is demonstrated via a thermoplastic component design scenario. An evaluation of the prototype revealed strengths and limitations that highlight future research challenges for developing KICAD tools aimed at supporting DFΣX.

Despite that paper-based freehand sketching is still widely used during the conceptual design phase, few are the tools available that allow designers to exploit sketches resulting from this activity at a later design phase. This paper reports the ongoing research on a prototype tool nicknamed mX-Sketch , which addresses this lack of support by linking freehand paper-based sketches with Computer-Aided Design (CAD) technology. Given that paper-based sketching is also used by designers outside their office to express their ideas, the rapid transfer and automatic generation of 3D virtual models from such sketches provide real-time design collaboration. Since a paper-based freehand sketch is inherently vague, the 3D form idea is clarified by means of symbols representing 2D geometric constraints (e.g. perpendicularity). As a result, mX-Sketch produces a parametric 3D virtual model, which can be potentially used downstream in the design process and exchanged in real time in collaborative design scenarios.

Since the design process is not just confined within an office, knowledge support must be provided to designers even when they are away from their workplace. The provision of knowledge is essential for designers to make decisions that have sound consequences on the product's life-cycle. Hence, designers require tools supporting them at considering the Life-Cycle Consequences (LCCs) of their decisions. With the increasing popularity of mobile devices such as PDAs, access to such knowledge can be greatly facilitated. This paper contributes a mobile Knowledge Management (mKM) system architecture aimed at providing designers situated in mobile work settings with 'LCCs' knowledge support.

The tool tip motion characteristics required for machining turned components on automatic lathes is a typical example where the compound movements generated by more than one cam plate are practically employed. Achieving problem specific tool tip motion characteristic requires considerable expertise and time in designing two separate planar cams, which when synchronized result in the desired turned component geometric shape. The objective of this paper is to present the analytical models adopted in the design, development and implementation of a computer based prototype tool for supporting the design and manufacture of such planar cams employed by automatic lathes. Evaluation of this prototype reveals that the use of cam profile blending models and edge vector based cam milling path approach, are a beneficial way of employing computers in industry to support the generation of cam plates that cater for profile blending problems inherent with synchronized cams.