Most additivemanufacturing (AM) processes are layer-based with three linear motions in the X, Y and Z axes. However, there are drawbacks associated with such limited motions, e.g. non-conformal material properties, s...
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Most additivemanufacturing (AM) processes are layer-based with three linear motions in the X, Y and Z axes. However, there are drawbacks associated with such limited motions, e.g. non-conformal material properties, stair-stepping effect, and limitations on building-around-inserts. Such drawbacks will limit additivemanufacturing to be used in more general applications. To enable 6-axis motions between a tool and a work piece, we investigate a Stewart mechanism anddeveloped a low-cost prototype system for multi-directional additivemanufacturing processes such as the Fuseddeposition modeling (FdM) and CNC Accumulation. The technical challenges in developing such an AM system are discussed including the hardware design, motion planning andmodeling, platform constraint checking, tool motion simulation, and platform calibration. Several test cases are performed to illustrate the capability of the developed multi-directional additivemanufacturing system.
This article presents an overview of the additivemanufacturing (AM) area, as known as rapidprototyping and more recently as 3d printing, and its expected impact in logistics. The AM processes are classified in vario...
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This paper presents a new technique of developing microstructure biosensors with magnetotactic bacteria by using three-dimensional (3d) bioprinting methods. A 3d bioplotter was used as a rapidprototyping tool to crea...
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ISBN:
(纸本)9781629934372
This paper presents a new technique of developing microstructure biosensors with magnetotactic bacteria by using three-dimensional (3d) bioprinting methods. A 3d bioplotter was used as a rapidprototyping tool to create a microstructure anddeposit the magnetotactic bacteria microorganisms into the microstructure. Silicon wafer was used as a target material for a substrate because it is a semiconductor and can be transformed to the micro electronic devices. We directly fabricate the structure on clear glass substrate with Polyjet from object so that we can observe these bacteria and their behaviors. The microstructure was designed to have a grid structure similar to hemocytometer so we can check and count the number of bacteria on the substrate and there is the reservoir with a small micro channel for supplying the fresh liquid medium into the culture chamber. This microstructure represents the prototype of the future micro bioreactor. The bacteria in the medium are deposited in 2 forms, the liquid medium and gel-like medium on the microstructure material. The magnetoctactic bacteria were applied as the biocatalyst for the chemical vapor deposition process to fabricate microcircuits from nanowire. The techniques presented in this paper introduces the possibility of utilizing the microorganisms to create the micro bioreactors or microcircuits for future biomedical applications.
In the last decades several computer-based procedures have been devised with the aim of speeding up the 3d reconstruction from a single image in the form of bas-relief. At the same time, the use of rapidprototyping(R...
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In the last decades several computer-based procedures have been devised with the aim of speeding up the 3d reconstruction from a single image in the form of bas-relief. At the same time, the use of rapidprototyping(RP) technology considerably spread enabling quick manufacture of 3d products directly from 3d modelling systems. The present paper presents a few consideration about different possible strategies for bas-reliefs manufacturing by using the main RP techniques(stereolithography(SLA), selective laser sintering(SLS), fuseddeposition modeling(FdM) and Polyjet/Multi-jet technology). A practical example is used for discussing pros and cons of the different alternatives.
In this paper preliminary results are summarized on the use of a combinedadditive Layer manufacturing (ALM) and indirect replication methodology to reconstruct reticular-like, three-dimensional (3d) structures mimick...
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ISBN:
(纸本)9780203181416
In this paper preliminary results are summarized on the use of a combinedadditive Layer manufacturing (ALM) and indirect replication methodology to reconstruct reticular-like, three-dimensional (3d) structures mimicking the 3d vascular network of the adult human thyroid gland. In a first step, we developed a fractal-like algorithm capable of modeling the native arterial distribution of the adult thyroid lobe, allowing for vascular growth within its geometrical domain. Although some arbitrary simplifications were adopted, yet the vascular density of the computational simulation showed good consistency with that of a native thyroid lobe. In a second step, single vascular branches were prototyped based on the STL output of the algorithm and ALM techniques, up to the achievement of a model having satisfactory geometrical/morphological accuracy. In a third step, the problem of reproducing the vascular geometry with a biocompatible polymer was addressed, anddifferent protocols of replication technology were evaluated. Limits and possible methodological solutions are discussed.
Rapidprototyping techniques are ideally suited to the manufacture of aerodynamics research models as these items usually consist of highly complex 3dimensional (3d) forms. The fabrication of complex curvatures on tr...
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ISBN:
(纸本)9783037855027
Rapidprototyping techniques are ideally suited to the manufacture of aerodynamics research models as these items usually consist of highly complex 3 dimensional (3d) forms. The fabrication of complex curvatures on traditional Computer Numerical Control (CNC) machines often requires the production of additional tooling supports to allow for full machining of all surfaces. Such a necessity often results in extra cost and fabrication time, as well as a potential loss in accuracy due to any repositioning required to allow machining of internal and external features. It is often necessary to divide the model into additional sections to allow for the machining of internal features which can cause issues with mismatching of adjacent surfaces. The inclusion of small or complex internal features and hollow sections may be problematic if not impossible. In contrast, many rapidprototyping techniques eliminate most of these manufacturing issues due to the additive nature of modem 3d printing processes. Popular techniques for the rapidprototyping of polymers include Selective Laser Sintering (SLS), Fuseddeposition modeling (FdM) and stereolithography. The basic technique reduces a 3d object into a series of thin 2d slices. The 2d slices are then "printed" vertically in succession to produce the final 3d item The "slicing" technique is readily compatible with the formation of complex 3d curvatures as well as internal and hollow features. In addition, any required tooling supports are produced simultaneously with the desired item, which greatly reduces processing time and loss of accuracy due to part repositioning. The necessity to produce a model from multiple sections to allow access for machining of internal features can in many cases be reduced significantly. The characteristics intrinsic to many modern 3d printing techniques are greatly beneficial for the production of complex wind tunnel models made from polymer. The current work describes the design process and features
Most of the additivemanufacturing (AM) equipments are patented commercial ones, but few are open-source systems (Fab@Home, Rep Rap, Candy Fab), enabling to disseminate the technology and to accelerate their developme...
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ISBN:
(纸本)9780203181416
Most of the additivemanufacturing (AM) equipments are patented commercial ones, but few are open-source systems (Fab@Home, Rep Rap, Candy Fab), enabling to disseminate the technology and to accelerate their development for specific needs. A machine called Fab@CTI was developed based on adaptations of Fab@Home. This paper shows the development of a printer head to enable the use of thermoplastics polymers in Fab CTI and Fab@Home machines by means of filament deposition modeling technology. Major parts of the extrusion head were built using AM machines and, in near future, the machine will be capable of building its own parts. It is also possible to adapt the extruder head to different filament diameters anddifferent melting temperatures (room temperature to 400 degrees C). Polycaprolactone was successfully used to build porous scaffolds with minimum pore size of 200 microns. Acrylonitrile Butadiene Styrene parts were built with an average layer thickness of less than 300 microns.
Technology of Rapidprototyping (RP) presents the technique that leads to quick manufacturing of real model using the scaling with support of three-dimensional software solution running in computer environment (CAd). ...
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ISBN:
(纸本)9780735410176
Technology of Rapidprototyping (RP) presents the technique that leads to quick manufacturing of real model using the scaling with support of three-dimensional software solution running in computer environment (CAd). First RP technique, Stereolithography, was developed by 3dsystems of Valencia, CA, USA. The company was founded in 1986, and since then, a number of different RP techniques have become available. Article deals with basic characteristics and problems in area of technology of Rapidprototyping with focus to Fuseddeposition modeling. It brings in the project of experimental gearbox design and its manufacturing with application of Rapidprototyping technology. The work was realized by students and employees of Faculty of manufacturing Technologies in Presov, Slovakia. Model with four gears was realized together with its gear changing mechanism. Production of gearbox was connected with problems arising from size of individual parts and included also the realization of final gearbox assembly.
This paper starts from the idea that combining processes of eCommerce and traditional commerce (blended shopping) can bring advantages for customers and retailer. One possibility to take the emerged individualization ...
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ISBN:
(纸本)9789898565082
This paper starts from the idea that combining processes of eCommerce and traditional commerce (blended shopping) can bring advantages for customers and retailer. One possibility to take the emerged individualization trend on consumer markets into account is to integrate latest rapidprototyping technologies (additivemanufacturing) in order to enhance the blended shopping concept. The availability of Internet can be seen as the enabler for such services. First blended shopping and rapidprototyping with its latest developments of additivemanufacturing (AM) are explained. Then their impacts on the aimed individualized blended shopping concept are depicted with the help of a use case. From this use case the benefits for business and consumers are derived and additionally the framework of a needed AM-toolkit is concretized. Finally the paper closes with a future outlook on the necessity of research in the field of individualization aspects of blended shopping and web standards.
additivemanufacturing (AM) or rapidprototyping (RP) has been widely used for the fabrication of tissue substitute in orthopedic and craniofacial surgeries. The AM techniques are used so as to eliminate the medical c...
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ISBN:
(纸本)9780203181416;9780415684187
additivemanufacturing (AM) or rapidprototyping (RP) has been widely used for the fabrication of tissue substitute in orthopedic and craniofacial surgeries. The AM techniques are used so as to eliminate the medical complications arising from the use of allografts and autologous tissues. To date, AM methods can be classified into several classes such as melt-dissolution deposition, particle-bonding, indirect and photosensitive techniques. These approaches are commercially available or custom-built AM systems and they have been shown to display micro-scaled features which are advantageous for cell migration, attachment as well as mass transportation of essential nutrients within the tissue engineered construct. In contrast to traditional tissue engineering (TE) approaches, AM-built constructs have significantly improved the cell proliferation rate in the interior of the tissue scaffolds. Modern AM approaches have since emerged as potential TE solutions to construct complex tissues and organs by the inclusion of living cells suspension or growth factor(s) as raw materials into the AM technology. The newly developed AM methods, which are also grouped as bioprinting and organ printing, are still at its infancy as reflected by existing literature. Nevertheless, more innovative AM-related approaches are anticipated in the future and, as suggested by the author, functional CAd-basedmodeling may possibly be the next state-of-the-art to AM technology.
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