International Journal of Computer Integrated Manufacturing. Jun2007, Vol. 20 Issue 4, p387-395. 9p. 7 Diagrams, 7 Charts.
RAPID prototyping, PROTOTYPES, CONCURRENT engineering, CAD/CAM systems, COMPUTER integrated manufacturing systems, and COMPUTER industry
Current rapid prototyping techniques have been used to produce freeform solid models. This usually involves new dedicated fabrication machines incurring costly capital additions, maintenance and materials. In the current paper, an approach is proposed where rapid layered prototypes are fabricated using standard generic 2D machining systems and commonly available sheet materials. The process necessitates the decomposition of a computer aided design (CAD) object into cross-sectional profile layers. From these machined profiles, they are then constituted to form the prototype. Several prototypes of varying sizes having quite complex internal and external profiles have been fabricated. A discussion into the merits and potential limitations of this approach is also made. [ABSTRACT FROM AUTHOR]
PROTOTYPES, MANUFACTURING processes, VIRTUAL reality, COMPUTER simulation, and STEREOSCOPIC views
This paper proposes a CAVE-based multi-material virtual prototyping (CMMVP) system for immersive stereoscopic visualisation and optimisation of multi-material layered manufacturing (MMLM) processes. The CMMVP system consists mainly of a suite of software packages for simulation of MMLM processes, integrated with a multi-screen CAVE-based virtual reality (VR) system, to create an immersive virtual environment for digital fabrication of multi-material product prototypes. In comparison with desktop-based or semi-immersive VR systems, the CMMVP system blocks out environmental disturbances such that designers can fully immerse in performing stereoscopic visualisation and quality analysis of the resulting multi-material prototypes for subsequent improvements of a product design. The CMMVP system facilitates advanced product design and helps reduce product development time and cost substantially. [ABSTRACT FROM AUTHOR]
International Journal of Product Development. 2004, Vol. 1 Issue 2, pN.PAG. 0p.
RAPID prototyping, RESEARCH, PLANNING, TECHNOLOGY, and REVENUE
This paper provides an overview of the information published in Wohlers Report 2003, a 270-page market study. The report addresses many aspects of rapid prototyping, including: industries served; applications; revenues; unit sales; forecasts. It also provides current information on industry trends and developments in the areas of service providers, advanced approaches to tooling, system manufacturers and technology advances in the USA, Europe, Asia and other parts of the world. The report covers research and development activities, growth trends in CAD solid modelling, rapid prototyping materials, medical modelling, rapid manufacturing and reverse engineering. Wohlers Report 2003 concludes with a discussion of the future of rapid prototyping -- where it is headed and what is expected -- to assist in strategic and tactical planning. [ABSTRACT FROM AUTHOR]
A stochastic model has been developed for studying the mechanical error in different rapid prototyping (RP) processes. Tolerances and clearances, which cause mechanical error, have been assumed to be random variables. The coordinates of a point on the work surface traced by the laser beam or the tip of the extruder head is expressed as a function of the random variables involved in the process. Using a unified approach for the RP processes, the mechanical error in the fused deposition process is analysed. In a numerical example, the mechanical error has been found for a grid of points traced by the nozzle tip. The three-sigma bands of the error in tracing example curves are plotted. This is the band in which the nozzle tips of 99.73% of machines, produced on a mass scale, lie for the given tolerances and clearances. Stringent values of tolerances and clearances reduce the error at the nozzle tip, but the cost of manufacturing and assembling the machines may become prohibitive. [ABSTRACT FROM AUTHOR]
International Journal of Manufacturing Technology & Management. 2013, Vol. 27 Issue 1-3, p47-73. 27p.
MANUFACTURING processes, RAPID prototyping, THREE-dimensional printing, SURFACE finishing, and MACHINE parts
The article discusses the role of build orientation on rapid prototyping or layered manufacturing (LM) and its impact on fabricated parts and the improvement of part quality. Topics include the LM process and the impact of build orientation on surface finish. It adds that build orientation improves parts quality and affects the manufacturing cost and part strength.
The article reports that the objects made of multiple materials are now increasingly being used in engineering applications. Such objects are also known as heterogeneous objects. To manufacture these heterogeneous objects by rapid prototyping , a computer added design model is required that contains both geometric information as well as material information of the objects.
Computers in Industry. Jun2009, Vol. 60 Issue 5, p349-363. 15p.
SPECIFICATIONS, BASES (Linear topological spaces), MEMORY, and FAMILIES
Abstract: This paper presents an approach based on topological hierarchy to representation and subsequent fabrication of functionally graded multi-material (FGM) objects by layered manufacturing. The approach represents an FGM object by material control functions and discretisation of slice contours. Based on the topological hierarchy of slice contours, material control functions are associated with contour families of some representative layers across the X–Y plane and along the Z-plane. The material composition at any location is calculated from the control functions, and the slice contours are discretised into sub-regions of constant material composition. The discretisation resolution can be varied to suit display and fabrication requirements. In comparison with pixel- or voxel-based representation schemes, this approach is computationally efficient, requires little memory, and facilitates fabrication of large and complex objects, which can be assemblies of FGM and discrete materials. The proposed approach has been incorporated with a virtual prototyping system to provide a practical and effective tool for processing FGM objects. [Copyright &y& Elsevier]
Journal of Manufacturing Systems. Jul2015, Vol. 36, p231-243. 13p.
PROCESS optimization, MANUFACTURING processes, CONSUMPTION (Economics), AEROSPACE engineering, and AUTOMOTIVE engineering
Layered manufacturing (LM) has evolved from the rapid prototyping (RP) method to a mainstream process for manufacturing high precision parts for aerospace, automotive and medical industries. LM inherits from RP several advantages including the ability to produce complex shapes, low cost and elimination of special tooling, as well as disadvantages of poor surface finish, poor dimensional accuracy, high build time and high waste. As LM is increasingly being accepted as a traditional manufacturing process, it has to consistently manufacture parts with minimal errors while keeping the material utilization to a minimum. This paper analyzes the effect of part orientation on two types of form errors, namely, cylindricity and flatness errors. An algorithm to calculate the optimal orientation for minimizing flatness and cylindricity errors is developed and tested with the help of two test cases. However, an optimal orientation for minimum form errors may result in a greater utilization of support structures which increases the material consumption in LM processes and therefore should be avoided. A voxel-based approach for calculating support structures has been developed in this paper which is then applied to minimize the volume of support structures while minimizing the cylindricity and flatness errors of the part features. This combined optimization is applied on two test parts and the results are provided. [ABSTRACT FROM AUTHOR]