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To present the findings of the research on the use of concurrent engineering in the development of polymeric based composite automotive clutch pedal. It covers the use of various IT such as expert system, FEA, CAD, mould flow and rapid prototyping in order to carry out various activities such as material selection, total design, design analysis and mould flow analysis.

The work started with the conceptual design of an automotive composite clutch pedal. Various design guides related to composite materials were followed. The final concept of the composite clutch pedal is developed using Pro/Engineer solid modelling package. Design analysis was carried out using LUSAS to study the optimum pedal lever cross section and the optimum rib patterns in pedal lever. Mould flow analysis was investigated to predict the behaviour of materials inside the injection moulding machine and the results are compared with experimental values. Rapid prototyping models were developed based on two techniques namely 3D printer and stereolithography and they are compared in terms of quality, time and cost.

In this study, the integrated IT tools enable the designer to design and manufacture automotive an composite clutch pedal at higher quality and faster time compared to a metal counterpart. By adopting composite design guides, weight saving from implementing composite materials in the clutch pedal is achievable. It is found that an expert system for material selection enables designer to select the suitable composite material for the clutch pedal by considering various parameters such as strength, modulus, density, manufacturing and economic constraints. Rapid prototyping models enable the designer to communicate effectively their design to other parties early in the design process. Mould flow analysis is carried out to predict the behaviour of material inside the mould and to design the optimum moulding parameters such as fill time, fill temperature and gate location.

In this study, the originality lies in the integration of various IT tools in the development of composite clutch pedal. The designer is exposed to various design and manufacturing issues from the implementation of such approach early in the design process.

It is likely that under modern-day conditions, design, designer and materials selection would follow a parallel continuum in a cycle. The attitude in materials selection confronts us as one of the substantial values directing the design. Therefore, it should be approached in certain criteria.

Today, designers have to put emphasis on not only the setting and style of the space they are designing, but also on the relationship between the materials used and the environment at the same time. In our day, designers have an intense awareness on the use of renewable resources. Hence, it is obvious that a special importance should be given to the fact that the materials are in a cycle of sustainable and recycled.

In this study, 15 design offices are asked the question of “what are the factors affecting your materials decisions and what are your selection criteria in general?” by using the interview technique. As a result of interviews conducted with design offices regarding their materials selection, many criteria are identified. It is seen that although sustainability is not clearly stated by designers among these criteria, it actively takes part in the content. In the light of answers provided and interviews, the relationship between materials selection criteria and sustainability will be examined over the standpoints of 12 offices that particularly mentioned the area of sustainability.

Combining of natural and synthetic materials in apparel products caused problems with material recovery, reuse, recycling, or composting at the end of product life. The purpose of this paper is to investigate the application of design for disassembly methods in the design and construction of men's jacket. With this type of design, consumers and manufacturers can easily compost, recycle, or reuse different materials and components at the end of the garment's usable life.

After analyzing the men's jackets available in the market and identifying obstacles to disassembly, the authors designed and constructed a man's jacket that can be easily disassembled. The jacket design for disassembly focused on material selection, jacket design, and stitch evaluation and selection. The disassembly time was also measured.

It was found that minimizing material diversity and sewing similar materials together whenever possible, replacing fusible interfacing with blind hemming stitches under the collar and on the backside of the lapel, and using an appropriate low density stitch to sew the wool outer shell and polyester lining together, can make the jacket disassemble easily into a compostable outer shell and recyclable lining within 1.5 min.

This research provided a pilot study demonstration of applying “design for disassembly” in apparel design and construction. The findings could be employed in different apparel products to help reduce environmental pollution and resource depletion problems related to the apparel industry.

PolyJet technology allows printing complex multi-material composite configurations using Voxel digital designs' capability, thus allowing rapid prototyping of 3D printed structural parts. This paper aims to investigate the processing and mechanical characteristics of composite material configurations formed from soft and hard materials with different distributions and sizes via voxel digital print design.

Voxels are extruded representations of pixels and represent different material information similar to each pixel representing colors in digital images. Each geometric region of a digitally designed part represented by a voxel can be printed with a different material. Multi-material composite part configurations were formed and rapidly prototyped using a PolyJet printer Stratasys J750. A design of experiments composite part configuration of a soft material (Tango Plus) within a hard material matrix (Vero Black) was studied. Composite structures with different hard and soft material distributions, but at the same volume fractions of hard and soft materials, were rapidly prototyped via PolyJet printing through developed Voxel digital printing designs. The tensile behavior of these formed composite material configurations was studied.

Processing and mechanical behavior characteristics depend on materials in different regions and their distributions. Tensile characterization obtained the fracture energy, tensile strength, modulus and failure strength of different hard-soft composite systems. Mechanical properties and behavior of all different composite material systems are compared.

Tensile characteristics correlate to digital voxel designs that play a critical role in additive manufacturing, in addition to the formed material composition and distributions.

Results clearly indicate that multi-material composite systems with various tensile mechanical properties could be created using voxel printing by engineering the design of material distributions, and sizes. The important parameters such as inclusion size and distribution can easily be controlled within all slices via voxel digital designs in PolyJet printing. Therefore, engineers and designers can manipulate entire morphology and material at each voxel level, and different prototype morphologies can be created with the same voxel digital design. In addition, difficulties from AM process with voxel printing for such material designs is addressed, and effective digital solutions were used for successful prototypes. Some of these difficulties are extra support material or printing the part with different dimension than it designed to achieve the final part dimension fidelity. Present work addressed and resolved such issued and provided cyber based software solutions using CAD and voxel discretization. All these increase broad adaptability of PolyJet AM in industry for prototyping and end-use.

The optimal material microstructures in pure material design are no longer efficient or optimal when accounting macroscopic structure performance with specific boundary conditions. Therefore, it is important to provide a novel multiscale topology optimization framework to tailor the topology of structure and the material to achieve specific applications. In comparison with porous materials, composites consisting of two or more phase materials are more attractive and advantageous from the perspective of engineering application. This paper aims to provide a novel concurrent topological design of structures and microscopic materials for thermal conductivity involving multi-material topology optimization (material distribution) at the lower scale.

In this work, the effective thermal conductivity properties of microscopic three or more phase materials are obtained via homogenization theory, which serves as a bridge of the macrostructure and the periodic material microstructures. The optimization problem, including the topological design of macrostructures and inverse homogenization of microscopic materials, are solved by bi-directional evolutionary structure optimization method.

As a result, the presented framework shows high stability during the optimization process and requires little iterations for convergence. A number of interesting and valid macrostructures and material microstructures are obtained in terms of optimal thermal conductive path, which verify the effectiveness of the proposed mutliscale topology optimization method. Numerical examples adequately consider effects of initial guesses of the representative unit cell and of the volume constraints of adopted base materials at the microscopic scale on the final design. The resultant structures at both the scales with clear and distinctive boundary between different phases, making the manufacturing straightforward.

This paper presents a novel multiscale concurrent topology optimization method for structures and the underlying multi-phase materials for thermal conductivity. The authors have carried out the concurrent multi-phase topology optimization for both 2D and 3D cases, which makes this work distinguished from existing references. In addition, some interesting and efficient multi-phase material microstructures and macrostructures have been obtained in terms of optimal thermal conductive path.

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Examines the ninth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

The purpose of this study is to develop a novel approach to designing locally programmed multi-material distribution in a three-dimensional (3D) model, with the goal of producing a biomimetic robot that could mimic the locomotion of living organisms.

A voxelized representation is used to design the multi-material digital model and the material distribution in the model is optimized with the aims of mimicking the deflection dynamics of a real-life biological structure (i.e. inchworms) during its locomotion and achieving smooth deflection between adjacent regions. The design is validated post-fabrication by comparing the bending profiles of the printed robot with the deflection reference images of the real-life organism.

The proposed design framework in this study provides a foundation for multi-material multi-functional design for biomimicry and a wide range of applications in the manufacturing field and many other fields such as robotics and biomedical fields. The final optimized material design was 3D printed using a novel multi-material additive manufacturing method, magnetic field-assisted projection stereolithography. From the experimental tests, it was observed that the deflection curve and the deflection gradient of the printed robot within the adjacent regions of the body agreed well with the profiles taken from the real-life inchworm.

This paper presents a voxelized digital representation of the material distribution in printed parts, allowing spatially varied programming of material properties. The incorporation of reference images from living organisms into the design approach is a novel approach to transform image domain knowledge into the domain of engineering mechanical and material properties. Furthermore, the novel multi-material distribution design approach was validated through designing, 3D printing and prototyping an inchworm-inspired soft robot, which showed superior locomotion capability by mimicking the observed locomotion of the real inchworm.

The relation of material design and textile science to the technologies of textile specialty products are discussed. Concept of material design is explained. The method of differential total material design is presented with an application example. The relation of material design to specialty textiles technology is analyzed. The relation of textile science to material design in terms of specialty textiles technology is also discussed. Some examples of scientific knowledge in terms of data base for material design are presented.

One of the critical reasons for the nonacceptance of additive manufacturing (AM) processes is the lack of understanding and structured knowledge of design for additive manufacturing (DfAM). This paper aims to assist designers to select the appropriate AM technology for product development or redesign. Using the suggestion provided by the design assist tool, the user’s design alterations depend on their ability to interpret the suggestion into the design without affecting the design’s primary objective.

This research reports the development of a tool that evaluates the efficacy values for all seven major standard AM processes by considering design parameters, benchmark standards within the processes and their material efficacies. In this research, the tool provides analytical and visual approaches to suggestion and assistance. Seventeen design parameters and seven benchmarking standards are used to evaluate the proposed product and design quality value. The full factorial design approach has been used to evaluate the DfAM aspects, design quality and design complexity.

The outcome is evaluated by the product and design quality value, material suit and material-product-design (MPD) value proposed in this work for a comparative assessment of the AM processes for a design. The higher the MPD value, the better the process. The visual aspect of the evaluation uses spider diagrams, which are evaluated analytically to confirm the results’ appropriateness with the proposed methodology.

The data used in the database is assumed to make the study comprehensive. The output aims to help opt for the best process out of the seven AM techniques for better and optimized manufacturing. This, as per the authors’ knowledge, is not available yet.