Browse the Catalog

Borrow eBooks, audiobooks, and videos from thousands of public libraries worldwide.

Harlequin Enterprises, Australia Pty Ltd

Looking for a library? Show libraries matching your search.

Rapid Prototyping of a High Sensitivity Graphene Based Glucose Sensor Strip

Discover a faster, simpler path to publishing in a high-quality journal.promises fair, rigorous peer review, broad scope, and wide readership a perfect fit for your research every time.

Click through the PLOS taxonomy to find articles in your field.

For more information about PLOS Subject Areas, clickhere.

AffiliationsKecks Advanced Materials Laboratory, Manufacturing Systems Engineering & Management, California State University of Northridge, Northridge, California, United States of America, Corrosion Research Laboratory, Manufacturing Systems Engineering & Management, California State University of Northridge, Northridge, California, United States of America

AffiliationsKecks Advanced Materials Laboratory, Manufacturing Systems Engineering & Management, California State University of Northridge, Northridge, California, United States of America, Corrosion Research Laboratory, Manufacturing Systems Engineering & Management, California State University of Northridge, Northridge, California, United States of America

AffiliationsKecks Advanced Materials Laboratory, Manufacturing Systems Engineering & Management, California State University of Northridge, Northridge, California, United States of America, Corrosion Research Laboratory, Manufacturing Systems Engineering & Management, California State University of Northridge, Northridge, California, United States of America

A rapid prototyping of an inexpensive, disposable graphene and copper nanocomposite sensor strip using polymeric flexible substrate for highly sensitive and selective nonenzymatic glucose detection has been developed and tested for direct oxidization of glucose. The CuNPs were electrochemically deposited on to the graphene sheets to improve electron transfer rates and to enhance electrocatalytic activity toward glucose. The graphene based electrode with CuNPs demonstrated a high degree of sensitivity (1101.356 A/mM.cm2), excellent selectivity (without an interference with Ascorbic Acid, Uric Acid, Dopamine, and Acetaminophen), good stability with a linear response to glucose ranging from 0.1 mM to 0.6 mM concentration, and detection limits of 0.025 mM to 0.9 mM. Characterization of the electrodes was performed by scanning electron microscopy (FESEM and SEM). The electrochemical properties of the modified graphene electrodes were inspected by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and amperometry.

Citation:Tehrani F, Reiner L, Bavarian B (2015) Rapid Prototyping of a High Sensitivity Graphene Based Glucose Sensor Strip. PLoS ONE 10(12): e0145036.

Editor:Nikolai Lebedev, US Naval Reseach Laboratory, UNITED STATES

Received:October 26, 2015;Accepted:November 30, 2015;Published:December 17, 2015

Copyright:© 2015 Tehrani et al. This is an open access article distributed under the terms of theCreative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Data Availability:All relevant data are within the paper and its Supporting Information files.

Funding:The authors have no support or funding to report.

Competing interests:The authors have declared that no competing interests exist.

Current glucose sensor technology relies mostly on enzymatic sensing strips that require repeated painful pricking methods to measure glucose concentration. The typical range of sensitivity for a blood glucose sensor is from 1.0 mM to 60 mM [1]. Non-diabetic and diabetic blood glucose levels fall within this range. A different approach for glucose determination is to use other fluid media. Saliva and tear fluid are alternatives to blood, but due to the low concentrations of analytes present in saliva, they require a very sensitive detection system. Tear glucose concentration is roughly 1/10 of the concentration of blood glucosefor saliva, the glucose concentration is even lower. Therefore, the commercial blood glucose sensors are not able to detect glucose in saliva or tears effectively. The primary focus of this research was to deliver a simple, reliable and accurate device that does not depend on chronic, invasive finger pricking, and does not rely on blood to determine glucose levels. An electrochemical sensor with a high degree of sensitivity and a desirable sensing range is achievable if it is made from graphene with a proper functionalization. Electrochemically deposited Copper nanoparticles were used for functionalization of the working electrode. A linear range suitable for detecting blood glucose levels in a human tear is obtained with significantly improving sensitivity below the 1.0 mM detection limit.

The performance of non-enzymatic glucose sensors relies mostly on two factors: the efficient electron transfer rate and an excellent catalytic material [2]. Graphenes properties have been the focus of many recent studies and graphene is expected to significantly surpass the functionality of present materials in many applications. Graphene has been attributed with a large surface area, based on theoretical calculations, 2630 m2/g for a single layer [3], excellent thermal conductivity (k = 5 103W/mK) [4], a fast electron transfer rate, high electrical conductivity ( = 64 mS/cm), and a large number of other material parameters such as mechanical stiffness, strength and elasticity. Some of these properties are derived from their delocalized bonds above and below the basal plane. Similar to carbon nanotubes (CNTs), functionalized graphene due to great surface area (both sides are available) has shown remarkable capacities in detection of nanoscale biomolecules such as glucose as it can also be enhanced with the metal nanoparticles [5]. Furthermore, the performance of the graphene based biosensors is highly dependent on the fabrication method for producing the graphene. Multiple approaches have been used to produce graphene, such as chemical vapor deposition (CVD), molecular beam epitaxy, mechanical exfoliation, thermal exfoliation and chemical exfoliation [4]. Yet, with these approaches additional processing is required to effectively transfer the material to a useful substrate such as a flexible polymer substrate.

Improving the catalytic reactions for the electrode can be done by deposition of metal nanoparticles (NPs) on to the highly conductive surface of graphene sheets. This produces composites with larger active surface areas and improved electron transfer rates, making an ideal material for the fabrication of electrochemical sensors [67]. Gold, silver, platinum, and nickel alloys have been used as catalytic materials for non-enzymatic glucose sensors [810] and they are capable of high sensitivity, however, poor selectivity and higher costs are limiting factors when compared to copper and its oxides, which have both high electrocatalytic activity and low cost [2]. Various copper nanostructures (nanoparticles, nanorods, nanocubes, nanodisks and nanowires) give large surface-to-volume ratios, fast electron transfer rate, superior catalytic ability and good sensing performance for non-enzymatic glucose sensors [1120]. Previous research for copper nanostructured sensors [141621] has reported good performance. Further improvements have been made using the graphene/CuNPs material for the composite electrode in this work. These improvements can be attributed to the higher electron transfer rate due to optimal CuNPs population that can absorb and catalyze more reactive substance and increase the speed of oxidation. These enhanced properties will lead to even greater interest for industrial applications when mass-produced graphene with high quality and performance can match laboratory prototypes.

Nano graphene platelets in powder form were obtained from Angstrom Materials LLC (N008-100-05). D-Glucose, Uric Acid, and Ascorbic Acid was purchased from sigma. All aqueous solutions were prepared using deionized water, using a Millipore water purification system with a minimum resistivity of 18.0 M-cm. The electrode morphology and micro
structure of the graphene and nanoparticles were characterized by scanning electron microscopy (SEM, JEOL JSM-6480LV, FESEM, Zeiss Ultra 55). Electrochemical measurements and resistance were performed using Gamry potentiostatic equipment, an electrochemical analyzer and multiple software packages (EIS300, PHE200, VFP600). The electrochemical measurements were based on a conventional three-electrode system with an Ag/AgCl as the reference electrode and PRG/CuNPs as the working electrode and bare graphene as the counter electrode. Electrochemical Impedance Spectroscopy (EIS) in 100 mM KCl solution containing 2mM K3[Fe(CN)6] + 2mM K4[Fe(CN)6] in the frequency range of 0.1 Hz to 100 kHz was used to obtain information on electron transfer rates between the electrolyte and the electrode surface. EIS normally includes a semicircular part and a linear part. The semicircular part at higher frequencies corresponds to the electron transfer limited process, and the diameter is equivalent to the electron transfer resistance (Rct), which normally reflects the charge transfer rate at the surface of the working electrode. The linear part at lower frequencies corresponds to the diffusion process. A straight line indicating Warburg resistance and the diffusion-limiting step in the electrochemical process [22] is a sign of good electrode conductivity. Cyclic Voltammetry (CV) was used for further investigation on the electrochemical behavior of the sensor strips. Ultimately, chronoamperometry experiments were used in order to study the amperometric response of the sensor toward different glucose concentrations.

For this investigation, simple processing integrates inexpensive materials (adhesive tape, graphene powder, copper tape, and silver conductive paste) to form the Graphene three electrode base. First, a PVC mask was prepared by removing a three-electrode channel into the PVC sheet using a laser engraving machine. Second, one side of the PVC sheet was taped using regular scotch tape, forming a flexible substrate with an adhesive three-electrode channel. Third, the graphene powder (0.25 mg for making a series of 4 strips) was placed on the three-electrode adhesive channel and physically rubbed against the surface of the adhesive Scotch Tape (SCT) in a gentle manner to form the uniform Physically Rubbed Graphene (PRG) electrodes. In the next two steps, electrodes were copper taped and then passivated by using a thin Kapton tape. Silver glue was used to enhance better connectivity in the copper-graphene intersection. An Ag/AgCl reference electrode was formed by gluing the tip of the electrode on the left side of the strip using a silver-silver chloride paste. The strip was stored in an ambient temperature for one day, for the paste to completely dry. An illustration of layers and the final strip is shown in theFig 1. The exposed area of the working electrode (the electrode in the middle), was adjusted to be 0.19 cm2(equivalent to the area of a circle with a diameter of 5mm). The processing method for the prototyping requires only several minutes of processing time at room temperatures, enables direct fabrication on flexible polymer substrates without an additional transfer step, and delivers strong surface adhesion between the few graphene layers and the flexible polymer substrates. Following the fabrication of the SCT/PRG base, the electrode was rinsed to remove loose graphene flakes and dried with low pressure argon gas to prepare for electrochemical deposition of copper nanoparticles.

a) raw materials from top to bottom, a thin Kapton tape used as the passivation layer; Copper tape used to form the sensor pad, Graphene powder used to form the three electrodes; PVC sheet with three laser-patented holes used to mask the substrate; Scotch tape used as the adhesive substrate, b) A drawing of the layers during assembly with the Scotch tape being masked. c) A drawing of the final sensor strip, ready for further modifications. d) A real sensor strip prototype, ready for further modifications.

CuNPs were electrochemically deposited on the surface of the working electrode. Since the sensitivity and the linear range of the sensor is highly dependent on the size and population density of CuNPs, the deposition of Copper nanoparticles on the working electrode is optimized systematically to achieve the smallest possible nanoparticles with a great population density. A large copper population will maximize the output signal of the biosensor due to an increased chemical reaction between the D-Glucose molecule and the CuNPs. The applied voltage during deposition improves the graphene surface and controls the electrodeposition parameters that contribute to optimal NP population with uniform distribution [23]. The formation of nuclei strongly depends on the interaction between the copper and the graphene. The abundant surface functional groups (−OH, COC, and −COOH) on graphene provide reactive sites for the nucleation and binding of metals [10]. According to Grujicic, and Pesic [23], the three factors of applied potential, solution concentration of the Copper sulfate and Sodium sulfate along with the deposition time were controlled for an optimum result. In order to obtain an optimized size and population density of the CuNPs, four DC potentials of -0.2 v, -0.4 v, -0.6 v, and -0.8 v vs. Ag/AgCl were applied to the working electrode immersed into a 5 mM CuSO4 + 50 mM Na2SO4 solution for 350 seconds. The size and population of the CuNPs on Graphene sheets were observed using FESEM of the samples. Amperometry experiments of the strips was carried out to evaluate the performance of each strip according to its deposition process.

Fig 2A & 2Bshow the SEM images of the irregular PRG that are vertically aligned on the adhesive surface of the SCT, creating a network of interconnected graphene sheets.Fig 2C & 2D, taken after the electrochemical deposition process of CuNPs on the PRG, show the FESEM images of the Copper nanoparticles are uniformly deposited on the graphene sheets. Among several applied potentials at the electrodeposition process for deposition of CuNPs on the SCT/PRG electrode, the applied potential of -0.60 v (vs. Ag/AgCl) demonstrated both the greatest amperometric signal response of the sensor, and formation of the finest CuNPs on the PRG sheets. Therefore, the optimal electrochemical deposition process results were identified to be achieved at a -0.60 v potential with a deposition time of 350 seconds using a 5 mM CuSO4 + 50 mM Na2SO4 solution without stirring of the solution.

a & b) SEM of bare PRG sheets immobilized on a scotch tape. c & d) FESEM images of Copper nanoparticles electrochemically deposited on the PRG sheets.

In order to characterize the charge transfer behavior of the working electrode, the EIS tests were conducted. The Nyquist plots (Fig 3) of the bare SCT/PRG electrode and the SCT/PRG/CuNPs electrode were compared. According to the Randles equivalent circuit (Fig 3, inset), it can be seen that the Rctfor the modified electrode with CuNps (SCT/PRG/CuNPs) was smaller than the bare graphene electrode (SCT/PRG); demonstrating that the SCT/PRG/CuNPs electrode has a higher charge transfer rate than the bare graphene electrode. The copper nanoparticles are acting as electron mediators in the electron transfer process [19]. Accordingly, the bare SCT/PRG indicates a resistance of 151 to the charge transfer at the surface of the working electrode and a Rs288 . After deposition of copper nanoparticles, the charge transfer of the electrode was reduced to 49 , and roughly the same Rs288 was calculated.

A comparison of the electrochemical behavior of the PRG/CuNPs composite was investigated by conducting a cyclic voltammetry (CV) experiment on the sensor in 0.1 M NaOH solution at a scan rate of 100 mV/s with successive addition of 0.25 mM, 0.50 mM, and 0.75mM of glucose. The oxidation of glucose starts at approximately 0.25 v, reaching an obvious shoulder peak at roughly 0.50 v, with the current continuing to increase with the increase in the potential (Fig 4A). The effect of scan rate on the oxidation of gluc
ose molecules using the SCT/PRG/CuNPs electrodes was investigated by preforming multiple cyclic voltammetry experiments with different scan rates, starting from 25 to 300 mV/s, with a scan step of 25 mV/s (Fig 4B). A linear correlation (R2= 0.93) between the anodic peak current and the square root of the scan rate was established (Fig 4B, inset plot), indicating the controllability of the glucose oxidation by adsorption of the molecules on the surface of the working electrode.

a) Cyclic voltammetry at a scanning rate of 100 mV/s in a 0.1 M NaOH solution that is used to characterize the electrochemical behavior of the PRG/CuNPs composite in the absence and presence of of 2 mM D-Glucose. b) Cyclic voltammetry performed to characterize the electrochemical behavior of the composite electrode in 0.1 M NaOH + 0.25 mM glucose at several scan rates ranging from 50 mV/ to 300 mV/s, with 25mV/s steps.

In order to obtain an optimized sensing potential, 5 different amperometric experiments were performed on one sensor using applied potentials of 0.30 v, 0.40 v, 0.50 v, 0.55 v, and 0.60 v, with successive additions of 0.1 mM glucose in a 100 mM NaOH solution. Results plotted inFig 5suggests 0.50 v to be the optimal applied potential because it produces the greatest step-like signal response upon the addition of glucose.

In order to evaluate the amperometric behavior of the sensor, an apmerometry experiment on the sensor was performed at the sensing potential of 0.50 v in a 0.10 M NaOH solution. In 25 seconds (the time required to achieve a stable current) after the beginning of the test, D-Glucose (0.1 mM) was added every 8 seconds to the solution to observe the amperometric response of the system. Step-like current responses were apparent within 2 seconds (the response time) upon addition of 0.10 mM glucose in the detection range of 0.1 mM to 0.7 mM (Fig 6A). Therefore, a linear relationship between the current and the glucose concentration in that range was established (Fig 6B). This range is significant for glucose determination using tear fluid. The linear regression equation is given by y = 206.39x+107.4; R2= 0.998. The glucose level at a current of 150 A, for example, would be (y-b)/m or (150107.4) A/206.39 = 0.21 mM. The amperometry data revealed detection limits of 0.025 mM to 0.9 mM. The sensitivity was calculated to be 1101.356 A/(mM.cm2). The rough mechanism for the oxidation of glucose in alkaline media at the copper modified electrode is believed to be the following: copper exposed to NaOH will oxidize into CuO [Cu + 2OH− CuO + H2O + 2e−]. Subsequently, CuO is electrochemically oxidized to Cu(III) species such as CuOOH or Cu(OH)4−[CuO + OH−CuOOH or CuO + H2O + 2OH− Cu(OH)4−+ e−]. Finally, glucose is oxidized by the Cu(III) species and forms hydrolyzate gluconic acid [Cu(III) + glucose gluconolactone + Cu(II)] [Gluconolactone gluconic acid (hydrolysis)] [1214]. For comparison, glucose sensor performance has been reported in multiple published papers [512142426]; several are listed inTable 1. The sensitivity of SCT/PRG/CuNPs using inexpensive, versatile, and flexible Scotch Tape, surpasses many of these electrode materials, which take advantage of highly conductive but expensive and inflexible glossy carbon substrate.

a) Amperometric response of the sensor with successive additions of 1mM D-glucose to the 0.1 M NaOH solution at the constant potential +0.50 v. b) Tear glucose range calibration curve.

The effect of 250 M Ascorbic Acid (AA), 250 M Uric Acid (UA), 100 M dopamine (DA), and 100 M acetaminophen (ACT), as electrochemically active interferents found with glucose in human serum, was investigated on the sensor. This was carried out by systematically examining the amperometric response of the sensor upon successive addition of these interferents with their respective concentrations, as compared to 0.3 mM glucose in the order shown inFig 7. The amperometric response of the sensor demonstrates no significant signals that can be observed for the interfering species. This is while obvious glucose oxidation signals were obtained before and after the addition of interferents. Therefore, the SCT/PRG/CuNps is highly selective towards glucose while the effects of AA, UA, DA, and ACT on the sensor were negligible.

The reproducibility and stability of the sensor were investigated systematically. In order to investigate the reproducibility of the sensor, first, nine identical samples were fabricated and stored in normal and similar ambient condition. Next, chronoamperometry experiments were performed on the nine samples by measuring their output current signals while adding 0.1 mM of glucose into a 100 mM NaOH solution while stirring. From the amperometric responses a reproducibility of 91% with an average sensitivity of 1106.9 A/mM cm2and a standard deviation of 37.7 was calculated from the 9 sensor samples (Fig 8B), suggesting a relatively high reproducibility rate. The stability of the sensor was studied by performing 10 consecutive amperometric (1 experiment/ 3 days) experiments on one single sensor strip. I/I0(I0= initial current response on the first experiment) that was used as the stability measure of the sensor shows only a 17.2% of signal loss in the sensor strip (Fig 8A) after 10 times of consecutive use over a 30-day period. The small percentage of the signal loss in the sensor indicates a relatively high stability of the sensor that can be attributed to the stability of the SCT/PRG/CuNPs electrode, both in the ambient condition and in the basic solution.

a) Stability of the sensor during a 30-day period with a total of 10 consecutive amperometric experiments. b) Reproducibility of the sensor among 9 samples indicating roughly 91% reproducibility with average sensitivity of 1106.9 A/mM cm2 and a standard deviation of 37.7.

The major limitation associated with our work is related to the fact that experiments were conducted in an in-vitro setup. However, this does not change the main findings in the study, since the focus of this work in establishing a robust linear amperometric correlation between glucose concentration and signal response was identified. Nevertheless, a rigorous in-vivo study of the biosensor is needed to evaluate its performance on actual human tear samples.

The concept of rapidly prototyping a highly sensitive graphene-based glucose sensor strip was proven in this study. This opens up an opportunity for a real application of the facile but competent biosensor strip, using a human tear sample. However, some challenges remain, including the direct sample collection by using the sensor strip without causing any harm to the delicate eye. These challenges should be addressed in a rigorously designed study of the strip as the future of this research. Such a study would involve non-invasive experiments for glucose sensing being performed on animal eyes, and subsequently, a clinical study of human eyes and tear samples.

It should be noted that the solid state application of graphene powder on Scotch Tape, or literally any other adhesive surface, is a versatile method of utilizing this wonder material for useful prototyping of practical devices. Additionally, the Graphene-Scotch Tape strip developed here should be seen as a versatile platform on which the application of variety of functionalization methods on it would be feasible. Therefore, rapid prototyping of conceptual graphene-based biosensor devices using such a platform is one way to advance this work. For instance, by using the same SCT/PRG platform, one may develop a SCT/PRG/Glucose Oxidase (GOx) bio-sensing strip by the GOx as the functionalizing agent. The use of the GOx instead the CuNPs is expected to allow a wider detection and linear range while delivering high level of sensitivity in the sensor

Furthermore, it should be considered that the compatibility of the sensors fabrication method with the screen printing technology would create opportunities for further development of the sensor in the following ways. First, the construction of a microfluidic channel on the strip would all
ow for a safe tear sample collection directly from the eye. Second, an accurate passivation and padding on the sensor strip would be expected to eliminate the human error during the fabrication step and increase the reproducibility rate of the sensor to percentages even higher than what is reported in this study. Third, mass production for commercialization of the biosensor.

The behavior of most nonenzymatic glucose sensors is a direct function of the electrode material on which the glucose is oxidized. Recent efforts have exploited different materials and fabrication processes for these electrodes. Nanocomposite structure of graphene-metals or metal oxides offer large surface area for the oxidation of glucose. In this research, an inexpensive, disposable graphene and copper nanocomposite through a rapid prototyping process for highly selective nonenzymatic glucose detection was developed and tested for direct oxidization of glucose. The CuNPs effectively improve electron transfer rates and enhance electrocatalytic activity toward glucose. The graphene based electrode with CuNPs displayed good sensitivity, stability, linear range, detection limit, and selectivity against interfering molecules.

I would like to thank my advisor, Prof. Bavarian for his complete support, advice and insight throughout the life of this study. I also would like to thank Lisa Reiner and the MSEM department of California State University of Northridge for providing the resources necessary for the completion of this study.

Conceived and designed the experiments: FT. Performed the experiments: FT BB. Analyzed the data: FT LR BB. Contributed reagents/materials/analysis tools: FT LR BB. Wrote the paper: FT LR.

For more information about PLOS Subject Areas, clickhere.

Is the Subject AreaGlucoseapplicable to this article?YesNo

Is the Subject AreaElectrochemistryapplicable to this article?YesNo

Is the Subject AreaElectrochemical depositionapplicable to this article?YesNo

Is the Subject AreaNanoparticlesapplicable to this article?YesNo

Is the Subject AreaElectrode potentialsapplicable to this article?YesNo

Is the Subject AreaElectron transferapplicable to this article?YesNo

Is the Subject AreaGlucose signalingapplicable to this article?YesNo

Is the Subject AreaNanomaterialsapplicable to this article?YesNo

PLOS is a nonprofit 501(c)(3) corporation, C2354500, and is based in San Francisco, California, US

Rapid Prototyping Journal Volume 21 Issue 2

With an OverDrive account, you can save your favorite libraries for at-a-glance information about availability.Find out moreabout OverDrive accounts.

This issue is a collection of the best papers from the 2014 SFF Symposium. This 3-day meeting was held in Austin, Texas August 4-6, 2014. It drew 334 researchers from universities, companies and national laboratories from all over the world, representing 17 countries. There were 199 talks and posters presented at this annual meeting. Based on evaluations of each presentation at the conference, 12 papers were identified as best papers from the conference. These are included in this special issue. The content represents the breadth of AM research

Rapid Prototyping Journal, Volume 21, Issue 2

Copy and paste the code into your website.

Rapid Prototyping Journal, Volume 21, Issue 2

International Conference on Additive Technologies

International Conference on Additive Technologies iCAT 2016The Rapid Prototyping and Innovative Manufacturing Network – RAPIMAN is organising the 6International Conference on Additive Technologies that will be held between November 29

Rapid development and the raise of awareness of possibilities offered by the emerging Additive Manufacturing technologies lead to several initiatives and funding schemes that try to promote the AM technologies to the industrial level. One of such initiatives and amongst the most prominent ones is Collaborative Research Center 814 – Additive Manufacturing, established in 2011 at the Friedrich – Alexander University Erlangen-Nrnberg. To promote the findings and astonishing results of their research work the team joined forces with RAPIMAN in organising the 6thiCAT – the conference that has strived to transfer the knowledge between academia and industry for the last 12 years.

The iCAT 2016 will be held in Nrnberg (Germany), Bavarias second-largest city and the unofficial capital of Franconia. Nrnberg is alive with visitors year-round, but especially during the world famous Christkindlesmarkt. Nrnbergs Christmas market (November 25 – December 24, 2016) is one of Germanys oldest fairs and located in the heart of Nrnberg.

of November we will make Nrnbergs airport a centerpoint of Additive Manufacturing and 3D printing. The participants will be hosted by:

The Collaborative Research Center 814 – Additive Manufacturing at Friedrich Alexander University Erlangen – Nrnberg, and

The Bayerisches Laserzentrum, Erlangen

The conference will be co-organised by the Production Engineering Institute of the University of Maribor and DAAAM International Vienna.

The conference will once again bring together experts, researchers, experienced users, and newcomers, from the additive manufacturing field.

Fabrication of Bone Tissue Engineering Scaffolds via Rapid Prototyping and CAD

ǰãĿʸ/֤˾ Fabrication of Bone Tissue Engineering Scaffolds via Rapid Prototyping and CAD

Fabrication of Bone Tissue Engineering Scaffolds via Rapid Prototyping and CAD

JOURNAL OF RARE EARTHS, Vol. 25, Suppl., Jun . 2007

porous P-TCP has been generally used as the material of tissue engineering bone scaffold. It has been certified to repair defective bone with compounded bone m m w matrix stem cell. The P-TCP powders used in this research were offered by Shanghai Tissue Engineering Research Center. Its average particle size w s I0 pm. a Blending powders of epoxy resinfnylon were used as binder compounded with P-TCP powders. Particle average size of the blending powders was 50 p m, which was determined by

an instrument (ZETASIZER 3000HSA, MANERN Inc . UK) . The blending was a low viscosity polymer mixture that was mainly used for powder coating and as fillers. This paper investigated the microstructure of sphere. An example is shown as Fig. 13. Designed rectangle block porous scaffolds had 21 mm length, 21 mm width, 5 mm height and three-dimensional periodic porous architectures. And its diameter was 800 p m,,B= 0.53. Then the models was exported to an SLS . machine (HRPS -1IIA, Huazhong university of science and technology, China) with STL file format, and then used to construct scaffolds by SLS processing. Three process parameters, i .e ., laser power, preheating temperature and scan speed, were mainly responsible for the amount of laser irradiation per unit area during fabrication on the SLS system. Since the energy density affecting the degree of sintering of the exposed powders, specimens with different quality could be obtained by varying theses SLS process parameters. By varying the process parameter, three groups of specimens comprising of different ratio of P-TCP/epoxy resin and nylon were fabricated. When laser power was kept as 12 W, the surface quality of specimens scaffold was better, and the yield strength rose obviously. Simultaneously, the scaffolds were built layer-by-layer using a powder layer thickness of 100 pm when preheating temperature was 50 T . And the scan speed was kept as 2500 mm s – l . The specimen is shown in Fig. 14.

Scaffold specimen with the specimen is 1 mm)

1 . 2 . 2 High temperature treatment To achieve bioceramic, the scaffolds have to be treated by high temperature. The scaffold specimens were taken into an experiment stove (sx2-1013, from zufa Ltd. China) to sinter. During the high temperature treatment, too fast temperature change may lead to thermal expansion mismatch and structure broken. Therefore the temperature had to been elevated very slowly in the range between room temperature and 600c. It was about 40 min to elevate the temperature from room temperature to 200c . Then it took 800 min to achieve 600c. Above 600c, the polymers were completely burnt out. And the sintering temperature ( 1100c ) could be reached during 250 min. When it was reached, the temperature was kept for 3 h . The cooling process had to be slowly and carefully performed, too. At last, a bioceramic scaffold could be obtained, The porosity checked was 71.29%. A scaffold treated by high temperature is shown as Fig. 15. Its SEM ( Scanning Electron Microscope ) picture is shown as Fig. 16.

Fig. 15 Fig. 13 Three-dimensional microstructure of scaffold designed with CAD (UG)

A scaffold treated by high temperature (each grid under the scaffold is 1 mm)

Bonetissueengineering… 9ҳ bioactivityanddegradat… 12ҳ …3D scaffoldfabricationMacroporousscaffoldswere fabricated by a combined …

…createdviathree-dimensionalfabricationtechni…

tissueengineeringINTRODUCTION The useofrapidprototyping(RP)andsolid freeformfabrication(SFF) techniques to constructbonerepairscaffoldsas …

DesignandFabricationofBoneTissueEngineeringScaffoldsviaRapidPrototypingandCAD. Journalofrare earths, 2007, 25(Sup. 2):379-383. [8] ɳ…

Fabricationoftitaniumscaffoldswith porosityand…

Fabricationoftitaniumscaffoldswith porosityand…Engineering, Korea University, Seoul, 136-703, …[7],rapidprototypingmethod [8], replication …

DesignandFabricationofBoneTissueEngineeringScaffoldsviaRapidPrototypingandCAD Original Research Article JournalofRare Earths In dentistry, …

…ofdynamic maskingrapidprototypingsystem for …

Developmentofdynamic maskingrapidprototyping…(2000), Scaffoldsintissueengineeringbone…(2003), FabricationofPLGAscaffoldsusing …

…on computer-designed nano-fibrousscaffolds

on computer-designed nano-fibrousscaffolds…Rapidprototyping;Tissueengineering; 3-D …fabrication(SFF) technique,andthebonetissue…

Freeze CastingofPorous HydroxyapatiteScaffolds. 1

Designandfabricationofstandardized hydroxyapatitescaffoldswith a de?ned macro-architecture byrapidprototypingforbone-tissue-engineeringresearch. J …

fabri catedviaselective laser sintering forbonetissueengineering[J]. …Fabricationofhydrogelscaffoldsus ingrapidprototypingfor softtissue…

RapidPrototypingTechniques inFabricationofthe BionicScaffoldsWU Mao- …poly ( l – lactic 1 acid )scaffoldsforbonetissueengineeringviapr…

ʡǨŹѧ2015ϵڶ¿ʷԾ

Ҫ3ѧۿ̰Ʒ,Թ

ҩýĸ״ǰԤⱨ(2013-2017))

ţӢ̰ģUnit2 Wish you were here.һʱ

ڽѧѧ㸨ÿһ(2015.1.16)

ĵԻվֻռϵ

TRIZ on Rapid Prototyping -A Case Study for Technology Foresight

Resolving Contradictions with 40 Inventive Principles

Industry Specific Inventive Principles

Resolving Contradictions with 40 Inventive Principles

Industry Specific Inventive Principles

By: Jörg Stelzner, Carlos Palacios, Tobias Swaton

Although TRIZ is a problem solving tool, the application of TRIZ instruments supports the strategic task such as Technology Foresight. These methods provide the ability to visualize future trends and helps to generate ideas to reach them. In this case study on the technology of Rapid Prototyping, the capability of TRIZ to support Technology Foresight was explored. Different tools were tested and their applicability for this objective were assessed.

TRIZ, ursprnglich als Instrument zur Problemlösung erarbeitet, kann auch die strategische Aufgabe der Technologiefrherkennung untersttzen. Unter Nutzung von TRIZ-Werkzeugen können mögliche Trends veranschaulicht und die Ideengenerierung untersttzt werden. In dieser Fallstudie wird TRIZ zur Untersttzung von Technologiefrherkennung anhand der Technologie Rapid Prototyping getestet und bewertet, sowie die Anwendbarkeit verschiedener TRIZWerkzeuge fr diese Aufgabenfelder beurteilt.

The major aims for Technology Foresight are to improve the competitiveness in the future as well as differentiating a company. New technology areas can be identified in order not to miss out on new trends in the future. Global changes and technology discontinuities must be anticipated to prevent companies from being run over by new technologies or competitors.

As part of the Master of Science program in Technology and Innovation Management at the University of Applied Sciences of Brandenburg in Germany, an approach to Technology Foresight was made by using TRIZ. At the first stage the method was studied, particularly on its ability to support Technology Foresight. The second part of the project was the application of the method on a technology. First intensive knowledge on Rapid Prototyping as the selected technology was acquired and the TRIZ tools to be applied were chosen. Then experimental data was collected and by discussing and applying TRIZ the problem to be solved was defined. The sources were expert interviews and consultations, a visit to the international trade-fair Euro Mold 2002, patent survey, rating, literature and internet research.

For companies focused on the strategy to reach competitive advantages by innovative products, the product development process is the main business activity. The crucial factor here is the time-to-market, consequently reducing the product development time cycle. The key factors are intensifying the data exchange on basis of shared databases in order to achieve an integrated product development process.

Accordingly, models and prototypes need to be fully integrated. The requirements on the prototyping process are holding up the closed data structure and maintaining the data applicable at every stage of the development process. Rapid Prototyping is a generative production process. By producing different layers and joining them to each other, a physical three-dimensional prototype will be generated (fig.1).

The process is entirely based on digital data. Different methods are available and work with different materials like resin, metal or ceramics. Depending on the application field, the appropriate method between concept modelling and functional prototyping, Rapid Tooling, Rapid Manufacturing and Rapid Repair will be selected. The benefits of Rapid Prototyping in order to support the fast product development are the constantly available data base, continuous up to date data and direct processing from three-dimensional data. Rapid Prototyping is an integral function of the computer integrated manufacturing process (CIM).

As a procedure for TRIZ on Technology Foresight, a methodology with six steps, developed by Ellen Domb was chosen. This method uses different tools, taken from four basic groups of tools including Analogous, Vision, Systematic and Knowledge (fig. 2)

The steps include the application of tactical and strategic TRIZ. In this case the steps for strategic TRIZ were used. Tactical TRIZ should be part of problem solving, in this case developing the next technology generation.

4.1. Formulate the Ideal Final Result (IFR)

Altshuller defined the IFR as a fantasy, a dream. It can not be reached, but it will allow us to build a path to the solution1. At the beginning of the case study the equation of Ideality has been used as a preview analysis to get an overview of the elements of the system and their functions. Then an object model helped to find out the Ideal Final Result.

Ideality is equal to all useful functions over all harmful functions plus costs. Useful functions for RP are the use of multiple materials, time reduction, automatisation and the construction of complex geometries. The harmful functions are the long preparation time, limited resolution, the need for model support structure, stairstepping, post-process, accuracy problems, poor physical properties, poor finish, data lost and material contraction. Cost factors are the high material prices and the expensive machines.

An object model of the technology, containing the basic elements, their function and the possible harm was made including the steps identification and elimination of help functions, so that the determination of synergy between elements and the elimination of side effects and a good abstraction of the system was accomplished (fig. 3).

With the next steps replace the performance component and elimination of the need, three possible Ideal Final Results were defined (fig. 4). Replacing the element virtual representation leads to possible aided sculpture, or the possibility of designing direct on the prototype. Replacing the machine it self leads to a combination of virtual reality and haptics instead of producing a prototype. Eliminating the need (generation of), leads to computer calculations instead of prototypes.

The Ideal Final Result helped to obtain an objective understanding of the technology, to formulate the key questions and to discuss many different evolving directions of the technology. Paradigms on the technology were broken.

4.2. Analyzing the history of the system

The S-curve is a powerful tool, to stay aware of the existence of the technology life cycle and helps to understand, at which maturity stage the technology is at present time. In difference to other S-curve- concepts, the TRIZ generated S-curve is related to base lines (fig. 5-8). Every base line has an unique pattern, and the combination of the base lines create the maturity S-curve. Building the S-curves requires literature, internet and patent research and further information from experts. The result graphs in the following steps were matched with the base lines, given by Altshuller. Numbers of patents (fig. 5) are based on the patents submitted yearly. The data was acquired by using web based patent databases like using boolean logic terms. The first patents are from 1982 and the number of patents steadily rose until the peak in 1999 was reached. After that year a decrease is visible.

Fig.5: Numbers of patents: Case data and positioning on the base line

The data to build the profitability line was not easy to gather. RP is a technology used world wide and the companies keep internal data secret. As an assumption, the

Fig. 6: Profitability: Case data and positioning on the base line

source: data acc. to Wohler T. (ed), (2000) P.27-41 and Wohler T. (1993- 2002)

annual turnover was chosen to represent the profitability of the technology. The data was taken from companys annual reports (1991-2002) and from Wohler associates international industry reports. The graph shows a clear boost in 1993. (fig 6)

For the performance indicators, speed, strength and accuracy were discussed as being the most representative factor. From expert interviews and ranking different indicators, accuracy (or layer thicknes
s) was chosen. The data was acquired by using internet search engines, and entering the terms thickness or accuracy. The data which could be related to a year was selected and used to build the graph. More accuracy means less layer thickness. To make this data comparable with the TRIZ base line, inverted numbers were used (fig. 7).

According to the applied knowledge and the impact of the invention to different fields, Altshuller divided inventions into 5 levels. In order to relate the level of invention according to the years, different possibilities like patent citation, or patent research with invention related keywords were considered. As most reasonable, the following steps were developed:

Analysing the history of the technology, searching and defining key inventions.

1. Assessing these key inventions in a matrix by using Altshullers classification.

2. Transforming the data to the graph (fig.8).

By compiling the four base lines, a mutual position was determined and matched to the S-curve (fig. 9). The most probable present position on the S-curve shows that RP is within the growth stage. Assumptions to be made here are that the technology has an high potential and it is worth investing in this technology.

4.3. Patterns of evolution, definition and selection

When the position of the technology is determined, its evolution has to be traced. The technology trends are defined with the aid of the 8 patterns of evolution purposed by Altshuller.

Fig.10:Pattern 7: Evolution toward micro-level and increased use of fields

source: acc. to Beaman, J.J. (1997) and Herb,R., Herb,Th., Kohnhauser,V. (2000), p.201

The pattern 7 (evolution toward micro-level and increased use of fields) was chosen as the most appropriate (fig. 10). The first stages of the pattern for RP were adapted from literature and the future evolution stages were deduced from the pattern. Suitable technologies at an early research level, like Laser Chemical Vapor Deposition (LCVD) or Holographic Interference Solidification (HIS) complete the pattern. They represent the maturity or aging of RP on the time axis. Another important trend according to pattern 5 (increased complexity then simplification), was recognized. With the emergence of 3-D printing substituting the complex Laser Sintering machines, a trend toward more simple machines can be stated.

4.4. Formulate the problem to be solved

Following the definition of the pattern of evolution the major barrier that RP has to surmount, is generating the prototypes in layers. This task can be understood as developing a one-step synthesising 3-D process. This statement was formulated as a problem to be solved. The cause-effect diagram was used to decompose the main problem in sub-problems, for an easier analysis and future solution (fig. 11).

Fig.11: Cause-effect diagram (fishbone or Ishikawa diagram)

source: acc. to Herb,R. Herb, Th. Kohnhauser V. (2000), p.88

At this point strategic TRIZ was completed. The next steps belong to tactical TRIZ and intend to solve the problem and select a development to be implemented.

The conclusions can be divided in two parts, concerning Rapid Prototyping and a reflection on TRIZ as method a for technology foresight.Although there is a final conclusion from the foresight process, each step can provide important ideas and benefits.

According to the Ideal Final Result, new ways of virtual reality including more interaction can be developed to support the product development process. A future without physical prototypes could be predicted. The position on the S-curve shows that RP is still in the growing stage and a high potential for investment can be assumed. Searching the next generation of RP, a non-layer-construction system and the use of serial-product materials was defined by the patterns of evolution. This conclusion can be materialized by considering the development of new methods like Laser Chemical Vapor Deposition (LCVD) or Holographic Interference Solidification (HIS).

TRIZ has an effective capacity as a problem solving tool, by defining global questions as a precise problem. Patent research is a key factor where professional assessment is needed. Finding out the profitability is not easy and needs the consideration of other indicators, for instance the turnover. Defining the level of invention is very subjective and the correlation to specific years is demanding. Another point is the difficult connection between the multiple TRIZ tools. Knowledge of this procedure is also decisive, so a TRIZ-experienced moderator is recommended. But still the most important feature of TRIZ is that it opens the way of thinking and provide an alternative vision-thinking.

This case study was presented at the 3rd international TRIZ congress in Zrich. Some comments about the case were added in order to improve future application of TRIZ for technology foresight.

1. It is important in this type of technology foresight studies to consider point of view of the costumer 3.

2. The S-curve based on the number of patents was made with all the yearly submitted patents. This approach was critisized during other presentation at the congress. It was proposed not to use the numbers of patents related to the technology, but only to take into account just the patents that consider the specific parameter that was chosen to follow the evolution of the technology.4

3. In figure 9, the S-curve was determined by matching the curve of each parameter to the S-curve. The conclusion was, that the technology should be in the growth stage and that RD effort directed to maximize performance and efficiency. But the curves can not been put together, because maybe each one have a different development speed.

Carlos Andres Palacios, 1973 (Colombia), Industrial Designer

Jörg Stelzner, 1965, (Germany) Dipl. Ing. Mechanical Engineer

Tobias Swaton, 1966, (Germany), Dipl. Ing. Architect

Altschuller, G.: And Suddenly the Inventor Appeared,

Technical Innovation Center, Inc., Worcester 1992

Beaman, J.J.: JTEC/WTEC panel report on Rapid Prototyping in Europe and Japan,

Castle Islands Co.: The worldwide Guide to Rapid Prototyping,

Domb, E.: Strategic TRIZ and tactical TRIZ: Using the technology evolution tools,

Gebhardt, A.: Werkzeuge fr die schnelle Produktentstehung,

2. eddition, Hanser Verlag, Mnchen/ Wien 2000

Herb, R., Herb, T., Kohnhauser,V.: TRIZ: Der systematische Weg zur Innovation,

Verlag moderne Industrie, Landsberg/ Lech 2000

Man, D.: Using S-curves and trends of evolution in RD strategy planning,

Oki Electric Industry Co., Ltd.: Applied engineering of Rapid Prototyping,

Severine G.: Application of TRIZ to Technology Forecasting, yarn spinning

Wohler, T. (ed.): Rapid Prototyping Tooling: Weltweite Branchenbersicht 2000.

In: Wohlers Report 2000. Wohlers Associates Inc.

Wohler, T.: State of the industry reports. In: Wohlers Report 2001.

Technology Maturity Using S-curve Descriptors

Book Review: Directed Evolution: Philosophy, Theory and Practice.

Voice of Customers Pushed By Directed Evolution

Algorithm for choosing technical contradiction

Analysis of TRIZs Invention Principles

Law Of System Completeness Hierarchies

Wow In Music Summertime In England

Generational Cycles Battlestar Galactica

Liquid on Paper Rapid Prototyping of Soft Functional Components for Paper Electronics

: Chem. Rev., 2007, 107, 2411-2502

Liquid on Paper: Rapid Prototyping of So…

Liquid on Paper: Rapid Prototyping of Soft Functional Components for Paper Electronics.

1.1] The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, School of Life Science and Technology, Xian Jiaotong University, Xian 710049, China [2] Bioinspired Engineering and Biomechanics Center (BEBC), Xian Jiaotong University, Xian 710049, China.

2.Bioinspired Engineering and Biomechanics Center (BEBC), Xian Jiaotong University, Xian 710049, China.

This paper describes a novel approach to fabricate paper-based electric circuits consisting of a paper matrix embedded with three-dimensional (3D) microchannels and liquid metal. Leveraging the high electric conductivity and good flowability of liquid metal, and metallophobic property of paper, it is possible to keep electric and mechanical functionality of the electric circuit even after a thousand cycles of deformation. Embedding liquid metal into paper matrix is a promising method to rapidly fabricate low-cost, disposable, and soft electric circuits for electronics. As a demonstration, we designed a programmable displacement transducer and applied it as variable resistors and pressure sensors. The unique metallophobic property, combined with softness, low cost and light weight, makes paper an attractive alternative to other materials in which liquid metal are currently embedded.

An Environment for Rapid Prototyping of Interactive Systems

Journal of Computer Science and Technology

An Environment for Rapid Prototyping of Interactive Systems

CAD Laboratory Institute of Computing Technology; Academia Sinica; Beijing; CAD Laboratory; Institute of Computing Technology;

An Environment for Rapid Prototyping of Interactive Systems

CAD Laboratory Institute of Computing Technology; Academia Sinica; Beijing; CAD Laboratory; Institute of Computing Technology;

This paper shows an environment which supports the development of multi-thread dialogue interactive systems.The environment includes several tools and run-time support programs for the design and implementation of the user interface of an interactive system.First,methods of user interface specifica- tion with Elementary Nets are discussed.Then,the syntax of a user interface specification language based on Elementary Nets and the pre-compiler for the language as well as a graphic editor for Elemen- tary Nets

This paper shows an environment which supports the development of multi-thread dialogue interactive systems.The environment includes several tools and run-time support programs for the design and implementation of the user interface of an interactive system.First,methods of user interface specifica- tion with Elementary Nets are discussed.Then,the syntax of a user interface specification language based on Elementary Nets and the pre-compiler for the language as well as a graphic editor for Elemen- tary Nets

; Ȩ;.An Environment for Rapid Prototyping of Interactive Systems[J] Journal of Computer Science and Technology , 1991,V6(2): 135-144

Zhao Jinghai; Liu Shenquan;.An Environment for Rapid Prototyping of Interactive Systems[J] Journal of Computer Science and Technology, 1991,V6(2): 135-144

[1] H.J.Genrich, Predicate/Transition Nets. Lecture Notes in Computer Science 254, 1987, 207-247.

[2] M.Green, The University of Alberta User Interface Management System. Proc.SIGGRAPH85 (SanFrancisco, Calif-,July 22-26, Computer Graphics,19:5(1985),205-213.

[4] R.D.Hill, Supporting concurrency synchronization in human-computer interaction: The Sassafras user interface management systems. ACM Trans. Graph.,5:3(1986),179-210

[5] K.Jensen, Coloured Petri Nets. Lecture Notes in Computer Science 254, 1987, 248-29l. ..

Rapid Prototyping and Solid Free Form Fabrication

ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part B: Mechanical Engineering

Journal of Biomechanical Engineering

Journal of Computational and Nonlinear Dynamics

Journal of Computing and Information Science in Engineering

Journal of Dynamic Systems, Measurement, and Control

Journal of Electrochemical Energy Conversion and Storage

Journal of Energy Resources Technology

Journal of Engineering and Science in Medical Diagnostics and Therapy

Journal of Engineering for Gas Turbines and Power

Journal of Engineering Materials and Technology

Journal of Manufacturing Science and Engineering

Journal of Micro and Nano-Manufacturing

Journal of Nanotechnology in Engineering and Medicine

Journal of Nondestructive Evaluation, Diagnostics and Prognostics of Engineering Systems

Journal of Nuclear Engineering and Radiation Science

Journal of Offshore Mechanics and Arctic Engineering

Journal of Pressure Vessel Technology

Journal of Solar Energy Engineering

Journal of Thermal Science and Engineering Applications

Journal of Verification, Validation and Uncertainty Quantification

Journal of Manufacturing Science and Engineering Volume 119 Issue 4B Research Paper

Rapid Prototyping and Solid Free Form Fabrication

McCormick School of Engineering and Applied Science, Northwestern University, Evanston, IL 60208-3111

Institute of Materials Science, The University of Connecticut, U-136, 97 North Eagleville Road, Storrs, CT 06269-3136

This article will give a brief review of the start-of-the-art in commercial practice and advanced research in the field of Rapid Prototyping with special attention to the additive methods of Solid Free Form Fabrication. Recent applications of this technology in computer integrated manufacturing environments will be outlined. Future applications and research in new materials will also be addressed.

Copyright © 1997 by The American Society of Mechanical Engineers

Topics:ManufacturingRapid prototypingComputer-integrated manufacturing

Learn about subscription and purchase options

Your Session has timed out. Please sign back in to continue.

You must be logged in as an individual user to share content.

Return to:Rapid Prototyping and Solid Free Form Fabrication

Copyright in the material you requested is held by the American Society of Mechanical Engineers (unless otherwise noted). This email ability is provided as a courtesy, and by using it you agree that you are requesting the material solely for personal, non-commercial use, and that it is subject to the American Society of Mechanical Engineers Terms of Use. The information provided in order to email this topic will not be used to send unsolicited email, nor will it be furnished to third parties. Please refer to the American Society of Mechanical Engineers Privacy Policy for further information.

Conley JG, Marcus HL. Rapid Prototyping and Solid Free Form Fabrication. ASME.

1997;119(4B):811-816. doi:10.1115/1.2836828.

Customize your page view by dragging and repositioning the boxes below.

Direct Printing of Capacitive Touch Sensors on Flexible Substrates by Additive E-Jet Printing With Silver Nanoinks

Effects of Interpass Idle Time on Thermal Stresses in Multipass Multilayer Weld-Based Rapid Prototyping

J. Manuf. Sci. Eng (February, 2013)

Mechanical Analysis of Ultrasonic Bonding for Rapid Prototyping

A Novel Control Approach for the Droplet Detachment in Rapid Prototyping by 3D Welding

A Novel Device for Producing Three-Dimensional Objects

Continuous Liquid Interface Production of 3D Objects: An Unconventional Technology and its Challenges and Opportunities

Divers Augmented Vision Display (DAVD)

Modular Elastic Lattice Platform for Rapid Prototyping of Tensegrity Robots

Hygroscopic Swelling Behavior of 3D Printed Parts due to Changes in Environmental Conditions

A Novel Methodology for the Creation of Customized Eruption Guidance Appliances

Hot Air Rises and Heat SinksChapter 26

Part 2, Section IIMaterials and Specifications

Companion Guide to the ASME Boiler and Pressure Vessel Code, Volume 1, Third EditionChapter 3

Section III: Subsections NC and ND Class 2 and 3 Components

Companion Guide to the ASME Boiler and Pressure Vessel Code, Volume 1, Third EditionChapter 7

Subsection NE Class MC Components

Companion Guide to the ASME Boiler and Pressure Vessel Code, Volume 1, Third EditionChapter 9

Companion Guide to the ASME Boiler and Pressure Vessel Code, Volume 1, Third EditionChapter 10

You do not have access to this content.

The American Society of Mechanical Engineers

Sorry!You do not have access to this content. For assistance or to subscribe, please contact us:

The alert will be sent to + $(inputtxtUserAlertEmailAddress).val(); );

Sign in or create your free personal ASME account. This will give you the ability to save search results, receive TOC alerts, RSS feeds, and more.

Shibboleth is an access management service that provides single sign-on protected resources. It replaces the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a users location or IP address. If your institution uses Shibboleth authentication, please contact your site administrator to receive your user name and password.

Slicing algorithm for rapid prototyping data processing

Slicing algorithm for rapid prototyping data processing

1.School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640, China;2.Department of Electronic Information Engineering, Wuzhou University, Wuzhou 543002, China

Aiming at the accuracy and efficiency in rapid prototyping parts, the slicing methods and slicing profile precision were analyzed. Using the STL initial file which was widely adopted by rapid prototyping manufacturing systems, a data processing algorithm utilizing extended approximation to reconstruct slicing profile and progressive thinning slicing was proposed. An accurate slicing profile was obtained, step effect error was effectively reduced and slicing efficiency was improved. In comparison to current adopted direct slicing and adaptive slicing algorithm, this algorithm had higher prototyping accuracy and efficiency. Simulation results and practical processing proved its validity, practicality and system adaptability.

ZHONG Shan,YANG Yong-qiang. Slicing algorithm for rapid prototyping data processing[J]. , 2011, 17(06): 0-0.

1CHOI S H, SAMAVEDAM S. Modeling and optimization of rapid puters in Industry,2002,47(1):39-53.

[2]KOC B, MA Yawei, LEE Y S. Smoothing STL file by max-fit biarc curves for rapid prototypingJ. Rapid Prototyping Journal,2000,6(3):186-203.

ZHUANG Xue-yin,ZHANG Li,WENG Xiao-qi,LI Hu-bin,LIU Ying-bo.

Real-time stream data processing framework for complex equipment condition monitoring

QI Kai-yuan1,2,3, HAN Yan-bo1, ZHAO Zhuo-feng1, MA Qiang2,3.

Real-time data stream processing and key techniques oriented to large-scale sensor data

Precise slicing method based on STL in RE/RP integrated system

BO Hong-guang, ZHANG Shu-ran, LIU Xiao-bing, ZHANG Nan, LIU Jian.

Data assimilation method of production capability state time-series prediction for steel enterprise

Automatic generation of support CAD model for sheet metal CNC incremental forming

Recent progress in slicing algorithm of rapid prototyping technology

[an error occurred while processing this directive]