Prototyping Methodology Research Articles

A novel prototyping method for die-level monolithic integration of MEMS above-IC

This work presents a convenient and versatile prototyping method for integrating surface-micromachined microelectromechanical systems (MEMS) directly above IC electronics, at the die level. Such localized implementation helps reduce development costs associated with the acquisition of full-sized semiconductor wafers. To demonstrate the validity of this method, variants of an IC-compatible surface-micromachining MEMS process are used to build different MEMS devices above a commercial transimpedance amplifier chip. Subsequent functional assessments for both the electronics and the MEMS indicate that the integration is successful, validating the prototyping methodology presented in this work, as well as the suitability of the selected MEMS technology for above-IC integration.

The performance of a prototype device designed to evaluate general quality parameters of X-ray equipment

The performance of radiological equipment can be assessed using non-invasive methods and portable instruments that can analyze an X-ray beam with just one exposure. These instruments use either an ionization chamber or a state solid detector (SSD) to evaluate X-ray beam parameters. In Brazil, no such instruments are currently being manufactured; consequently, these instruments come at a higher cost to users due to importation taxes. Additionally, quality control tests are time consuming and impose a high workload on the X-ray tubes when evaluating their performance parameters. The assessment of some parameters, such as the half-value layer (HVL), requires several exposures; however, this can be reduced by using a SSD that requires only a single exposure. One such SSD uses photodiodes designed for high X-ray sensitivity without the use of scintillation crystals. This sensitivity allows one electron-hole pair to be created per 3.63eV of incident energy, resulting in extremely high and stable quantum efficiencies. These silicon photodiodes operate by absorbing photons and generating a flow of current that is proportional to the incident power. The aim of this study was to show the response of the solid sensor PIN RD100A detector in a multifunctional X-ray analysis system that is designed to evaluate the average peak voltage (kVp), exposure time, and HVL of radiological equipment. For this purpose, a prototype board that uses four SSDs was developed to measure kVp, exposure time, and HVL using a single exposure. The reproducibility and accuracy of the results were compared to that of different X-ray beam analysis instruments. The kVp reproducibility and accuracy results were 2% and 3%, respectively; the exposure time reproducibility and accuracy results were 2% and 1%, respectively; and the HVL accuracy was ±2%. The prototype's methodology was able to calculate these parameters with appropriate reproducibility and accuracy. Therefore, the prototype can be considered a multifunctional instrument that can appropriately evaluate the performance of radiological equipment.

Designing in complexity: Simulation, integration, and multidisciplinary design optimization for architecture

While the overall performance of buildings has been established to be heavily impacted by design decisions made during the early stages of the design process, design professionals are typically unable to explore design alternatives, or their impact on energy profiles, in a sufficient manner during this phase. The research presents a new design simulation methodology based on incorporating a prototype tool (H.D.S. Beagle) that combines parametric modeling with multi-objective optimization through an integrated platform for enabling rapid iteration and trade-off analysis across the domains of design, energy use intensity, and finance. The research evaluates how the proposed method impacts design simulation processes, by either enabling and/or disrupting the early stages of design decision making. This simulation technology is presented through two major experiment sets: (1) a series of hypothetical cases emulating the architecture, engineering, and construction (AEC) design modeling and simulation process using our integrated simulation framework and technology; and (2) a pedagogically based experiment used for establishing benchmarks. Through these experiment data sets, both quantitative and qualitative data are collected, including human designer and computational analysis speeds, quantity of generated design alternatives, and quality of resulting solution space as defined by the evaluation metric of this research. The affordances for incorporation of real world design complexity into our computational design prototype and simulation methodology are discussed through both the enabling and the disruptive impact on the early stages of the design process.

Rapid laser prototyping of valves for microfluidic autonomous systems

Capillary forces in microfluidics provide a simple yet elegant means to direct liquids through flow channel networks. The ability to manipulate the flow in a truly automated manner has proven more problematic. The majority of valves require some form of flow control devices, which are manually, mechanically or electrically driven. Most demonstrated capillary systems have been manufactured by photolithography, which, despite its high precision and repeatability, can be labour intensive, requires a clean room environment and the use of fixed photomasks, limiting thereby the agility of the manufacturing process to readily examine alternative designs. In this paper, we describe a robust and rapid CO2 laser manufacturing process and demonstrate a range of capillary-driven microfluidic valve structures embedded within a microfluidic network. The manufacturing process described allows for advanced control and manipulation of fluids such that flow can be halted, triggered and delayed based on simple geometrical alterations to a given microchannel. The rapid prototyping methodology has been employed with PMMA substrates and a complete device has been created, ready for use, within 2–3 h. We believe that this agile manufacturing process can be applied to produce a range of complex autonomous fluidic platforms and allows subsequent designs to be rapidly explored.

Quantitative analysis of dendron-conjugated cisplatin-complexed gold nanoparticles using scanning particle mobility mass spectrometry

We report a high-resolution and traceable method to quantify the drug loading on nanoparticle-based cancer therapeutics, and demonstrate this method using a model cisplatin functionalized dendron-gold nanoparticle (AuNP) conjugate. Electrospray differential mobility analysis (ES-DMA) provides upstream size classification based on the electrical mobility of AuNP conjugates in aerosol form following electrospray conversion from the aqueous suspension. A condensation particle counter (CPC) and inductively coupled plasma mass spectrometer (ICP-MS) provide the principal downstream quantification. CPC and ICP-MS yield complementary number-based and elemental mass-based particle size distributions, respectively. Conjugation using three different dendron formulations was differentiated based on changes in the mean mobility particle size. The subsequent cisplatin complexation to the dendron conjugates was quantified by coupling ES-DMA with ICP-MS. Discrete AuNP clusters (e.g., dimers, trimers) could be resolved from the relative quantity of atoms (i.e., Au and Pt) per particle after separation by ES-DMA. Surface density of cisplatin on Au was shown to be proportional to the density of carboxylic groups present and was independent of the state of AuNP clustering. Additionally, we found that colloidal stability of the conjugate is inversely proportional to the surface loading of cisplatin. This study demonstrates a prototype methodology to provide traceable quantification and to determine other important formulation factors relevant to therapeutic performance.

Performance Evaluation Approach for Multi-Tier Cloud Applications

Complex multi-tier applications deployed in cloud computing environments can experience rapid changes in their workloads. To ensure market readiness of such applications, adequate resources need to be provisioned so that the applications can meet the demands of specified workload levels and at the same time ensure that service level agreements are met. Multi-tier cloud applications can have complex deployment configurations with load balancers, web servers, application servers and database servers. Complex dependencies may exist between servers in various tiers. To support provisioning and capacity planning decisions, performance testing approaches with synthetic workloads are used. Accuracy of a performance testing approach is determined by how closely the generated synthetic workloads mimic the realistic workloads. Since multi-tier applications can have varied deployment configurations and characteristic workloads, there is a need for a generic performance testing methodology that allows accurately modeling the performance of applications. We propose a methodology for performance testing of complex multi-tier applications. The workloads of multi-tier cloud applications are captured in two different models-benchmark application and workload models. An architecture model captures the deployment configurations of multi-tier applications. We propose a rapid deployment prototyping methodology that can help in choosing the best and most cost effective deployments for multi-tier applications that meet the specified performance requirements. We also describe a system bottleneck detection approach based on experimental evaluation of multi-tier applications.

The Pianist: Musical Mobile Application

In this paper, the process of developing a musicalmobile application has been described. The main motivation for this product is to support Samsung BADA apps market. We have developed this product based on two perspectives: educational and entertainment. The product can teach users how to play piano and at the same time, they can use it for fun, i.e., just to play piano like a real piano instrument. Firstly, we have studied and analysed the similar current products to know and understand the main functions of such product. Later we used prototype methodology, the final product generated after 8 prototypes. As a conclusion, this product (The Pianist) introducing a smart phone as a musical instrument which can be used for learning and playing piano.

Industrial ecology at factory level: a prototype methodology

The concept of sustainable manufacturing is a form of pollution prevention that integrates environmental considerations in the production of goods while focusing on efficient resource use. Taking the industrial ecology perspective, this efficiency comes from improved resource flow management. The assessment of material, energy and waste resource flows, therefore, offers a route to viewing and analysing a manufacturing system as an ecosystem using industrial ecology biological analogy and can, in turn, support the identification of improvement opportunities in the material, energy and waste flows. This application of industrial ecology at factory level is absent from the literature. This article provides a prototype methodology to apply the concepts of industrial ecology using material, energy and waste process flows to address this gap in the literature. Various modelling techniques were reviewed and candidates selected to test the prototype methodology in an industrial case. The application of the prototype methodology showed the possibility of using the material, energy and waste resource flows through the factory to link manufacturing operations and supporting facilities, and to identify potential improvements in resource use. The outcomes of the work provide a basis to build the specifications for a modelling tool that can support those analysing their manufacturing system to improve their environmental performance and move towards sustainable manufacturing.

MIMO Transmission Using a Single RF Source: Theory and Antenna Design

An approach for transmitting multiple signals using a single switched parasitic antenna (SPA) has been recently reported. The idea there is to map the signals to be transmitted onto a set of basis functions that serve as “virtual antennas” in the beamspace (i.e., wavevector) domain. In this paper, we generalize the derivation of the antenna pattern basis functions regarding a three-element SPA of arbitrary radiating elements, within a symmetric array topology, for multiplexing signals in the wavevector domain (using different beampatterns) rather than in the hardware antenna domain with multiple feeding ports. A fully operational antenna system example is modeled, optimized regarding its return loss and the power imbalance between the basis functions, and finally realized. The measurements of the SPA show good agreement with the simulated target values, revealing an accurate design approach to be adopted as a fast SPA prototyping methodology. The SPA has been successfully employed for multiplexing two binary phase-shift-keying (BPSK) datastreams over-the-air, thus paving the way for practically compact and highly efficient MIMO transceiver designs.

Virtual prototyping and pre-sizing methodology for buck DC–DC converters using genetic algorithms

In this article, the authors study the pre-sizing approach of DC–DC buck converters useful for electronics and system designers. The pre-sizing step in an indutrial process is suitable to obtain a preliminary precise sizing of a sub-system (here a buck DC–DC converter): it permits the system designer to perform a feasibility analysis of an overall system (e.g. that contains a buck DC–DC converter). First, static modelling of power devices is proposed: MOSFET, diode, inductor and heatsink. According to an industrial context, the MOSFETs, diodes and heatsinks fitting curves are issued from the manufacturer's datasheets. Second, the objective functions are explained in the case of mixed integer programming problems. Then, the optimisation variables and constraints are highlighted. Third, a section describes the choice of a multi-objective optimisation technique that leads to genetic algorithms (GAs). Fourth, the optimisation results are given. The choice of a final solution of the pre-sizing approach is discussed, considering additional constraints such as diode and MOSFET junctions temperatures, switching frequency etc. The authors focus on the general aspect of the optimisation method proposed here. It can also be used by power electronics designers with the help of additional constraints in accordance to their specific applications.

Evidence for farmers’ active involvement in co-designing citrus cropping systems using an improved participatory method

Agricultural policymakers are addressing the sustainable development issue by designing new agricultural systems. Farmers are ultimately asked to make deep changes at field scale. Designing cropping systems has previously been done using prototyping methodologies. Prototyping methodologies use a five-step designing process at field scale and request multicriteria analysis of the resulting prototypes. However, sustainable dynamics implies considering changes at larger scales, farm and region, as well as creating feedback and facilitating participation of all the stakeholders involved in the process. Here we studied citrus production in Guadeloupe, French West Indies, where farmers must reduce pesticide loads despite unresolved weed control issues. We designed the DISCS method, which stands for “participatory redesign and assess innovative cropping systems”, to improve classical prototyping methods by implementing a multi-scale, multi-stakeholder, participatory approach. Compared to classical prototyping methods, the DISCS method differs by implementing three progress loops, at experimental field, farm, and regional scales. Three categories of professional stakeholders are involved: farmers, researchers, and agricultural advisers, who are collectively in charge of designing and testing cropping system prototypes. In addition, local public stakeholders including representatives of state institutions are consulted. Progress is assessed using scale-specific sets of indicators. The DISCS method was applied to develop low-pesticide citrus cropping systems. Five weed control prototypes were jointly designed by citrus farmers and researchers, and two multicriteria assessment tools were built for use at the experimental station and on the farms. Results show that involved farmers transferred the new techniques to their own farms on their own initiative, thus spontaneously becoming pilot farmers. The DISCS method is therefore the result of a co-design process between farmers and researchers. The DISCS method creates an ongoing dynamic relationship between agricultural and public stakeholders to build a solution that can continuously be adjusted to stakeholders’ expectations.

EM-based synthesis and design of bandpass waveguide filters including manufacturing effects with FEST 3D

This article aims at the industry interest on automated design tools that are able to take into account manufacturing effects. First, an efficient design strategy for bandpass waveguide filters including the rounded corners arising from low-cost manufacturing procedures is presented. This technique is based on a recent enhanced prototype and synthesis methodology able to consider the real structure parts. Using the resulting electromagnetic (EM)-based synthesis technique, an excellent structure is extracted, which requires, at most, only a slight final EM optimization. Second, this article presents analytical expressions providing error estimates for the different filter performances in terms of manufacturing tolerances. From such expressions, designers can determine the tolerance to be requested for a tuning-less implementation. Moreover, they can also be used to set the convergence criterion for the synthesis procedure. A fully automated design tool of bandpass waveguide filters able to consider manufacturing impairments has been developed and integrated in the commercial software Full-wave EM Simulation Tool 3D (FEST 3D). © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2012.

Design and implementation of a novel sliding mode sensing architecture for capacitive MEMS accelerometers

We propose novel feedback control and sensing schemes based on sliding mode control (SMC) for closed-loop micro-accelerometers as alternative digital control architectures to sigma–delta (ΣΔ) approaches. The under-damped micro-device has been designed in Coventorware, fabricated in SOIMUMPs (25 µm thick structural layer) technology and experimentally characterized using a Polytec MSA-500 (micro-system analyzer) equipment. To verify the system architecture robustness, the application of SMC is extended to an over-damped accelerometer model. In either case, the SMC demonstrates the repositioning of the proof mass to null position; however, the over-damped model exhibits shorter transition time (15 ms for 1g acceleration) due to the increased damping. In addition to that, we extend the usage of SMC beyond the classical actuation problem to a novel sensing problem where we demonstrate the extraction of the external acceleration measurement from the switching behavior along the sliding surface. An optimized fixed-point implementation is targeted on a field-programmable gate array (FPGA) using rapid prototyping methodology, where the new proposed method has been compared for reference with a control scheme that employs a ΣΔ modulator. The SMC-based architecture is advantageous in terms of hardware complexity, and the control of the number of degrees of freedom required by an inertial measurement unit can be accommodated on a low-cost FPGA device. SMC offers a sound theoretical framework for the nonlinear control of inertial sensors.

ELDAMeth: An agent-oriented methodology for simulation-based prototyping of distributed agent systems

In application domains, such as distributed information retrieval, content management and distribution, e-Commerce, the agent-based computing paradigm has been demonstrated to be effective for the analysis, design and implementation of distributed software systems. In particular, several agent-oriented methodologies, incorporating suitable agent models, frameworks and tools, have been to date defined to support the development lifecycle of distributed agent systems (DAS). However, few of them provide effective validation methods to analyze design objects at different degrees of refinement before their actual implementation and deployment. In this paper, ELDAMeth, a simulation-based methodology for DAS, which enables rapid prototyping based on visual programming, validation, and automatic code generation for JADE-based DAS, is presented. ELDAMeth can be used both stand-alone for the modeling and evaluation of DAS and coupled with other agent-oriented methodologies for enhancing them with simulation-based validation. In particular, the proposed methodology, which is based on the ELDA (Event-driven Lightweight Distilled StateCharts-based Agents) agent model, provides key programming abstractions (event-driven computation, multi-coordination, and coarse-grained strong mobility) very suitable for highly dynamic distributed computing and is supported by a CASE tool-driven iterative process seamlessly covering the detailed design, simulation, and implementation phases of DAS. A simple yet effective case study in the distributed information retrieval domain is used to illustrate the proposed methodology.

A design-based research case study documenting a constructivist ID process and instructional solution for a cross-cultural workforce

As the need for instructing a globalized workforce increases, instructional designers must embrace the constraints and the opportunities these projects provide in order to move the field of cross-cultural instructional design (ID) forward. Cross-cultural projects offer multiple avenues for growth in ID practice, overcoming cultural barriers, and a venue to apply and test contemporary models, methodologies, and theories in ID. This design-based research case study employed a rapid prototyping methodology and the constructivist ID model, Layers of Negotiation, to collect critical cultural information for the design of this cross-cultural instruction. Instructional strategies deemed effective for instructing an unskilled workforce in Dubai, United Arab Emirates, included job aids, situated learning and apprenticeship principles consisting of modeling, coaching and scaffolding. Use of the constructivist ID model and instructional solution for a cross-cultural workforce for The Dubai Mall are presented. Evaluation results indicate the success of the instructional strategies varied dependent upon worker culture, and the sequential nature of the instructional strategies.

Control of the electromagnetic compatibility: An issue for IC reliability

This paper deals with the use of two main standard modeling approaches in order to control the electromagnetic compatibility of an IC before manufacturing. An application is given in the case of a complex mixed circuit which is an Analog to Digital Converter (ADC) embedded in a microcontroller. The digital core (DC) of the microcontroller consumes dynamic currents which generate internal disturbances and, as a consequence, a loss of the ADC accuracy is observed. At first, the conducted emission of the DC is estimated by using the ICEM-CE model. Then, the ADC immunity is modeled with ICIM-CI methodology. Based on these two models, a simulation at the chip level is performed to estimate the loss of accuracy of this ADC. Finally, this study is the first step in the development of a methodology for virtual prototyping allowing, from the design, the evaluation of the integrated circuit sensitivity to electromagnetic interference in order to improve its reliability.

A novel design method for electromagnetic bandgap based waveguide filters with periodic dielectric loading

An extremely rapid, versatile prototyping methodology is developed for waveguide filters with periodic dielectric loading which enables direct dimensional synthesis of the unit cell starting from given design objectives. A prototype filter has been designed using a low dielectric constant material and built for the purposes of testing the feasibility of the proposed approach. Our numerical results are compared with an independent commercial software package and also with experimental measurements. Simulation results are also presented for a filter loaded high dielectric constant material. In both cases the results are in excellent agreement with the theory and demonstrate the validity and the applicability of the proposed method.

Integrated Multiscale Methodology for Virtual Prototyping of Porous Catalysts

The microstructure of the support determines a key property of porous catalysts—effective diffusivity. Typically, supporting materials with bimodal pore size distribution are used that involve both meso- and macropores. Spatial distribution of active metal crystallites within the porous support then influences reaction rates and conversions. To optimize the catalyst support microstructure and ultimately the whole catalyst, it is necessary to relate quantitatively the morphological features of the porous structure both to its preparation conditions and to the final transport properties and catalyst performance under reaction conditions. In this paper we demonstrate the application of novel models based on the generalized volume-of-fluid method and 3D digital reconstruction of a porous structure. The procedure includes simulation of porous support formation (virtual packing of primary particles of defined shapes and sizes), drying and crystallization of impregnated metal solution (growth of metal nanoparticles), and solution of reaction and transport within the final virtual catalyst structure to obtain volume-averaged reaction rates that are then used in a full-scale model of a catalytic monolith reactor. A parametric study is performed to investigate the effects of the sizes of primary particles (influencing the meso- and macroporosity and pore sizes) and active metal impregnation conditions (influencing the distribution of active catalytic surface area) on the macroscopic activity of a catalytic monolith with Pt/γ-Al2O3 washcoat used for automotive exhaust gas aftertreatment.

Quality modelling and analysis of electroplating system using graph theory matrix approach

The quality of electroplating products depends upon conformance to requirements of the customer. These requirements are translated into design specifications of all the contributing factors and subsystems up to component level of the electroplating system. The quality of interaction amongst different subsystems, sub-subsystems and other factors that affect the quality of products are considered here. These are modelled using graph theory and matrix algebra as quality graph, quality matrix and quality permanent function of the electroplating product. A number of analytical tests derived from these models help to carry out optimum selection of qualities of subsystems and interactions for designing competitive electroplating products. Evaluation, ranking and comparison procedures can be developed with the help of models proposed herein. Coefficients of similarity and dissimilarity are developed for comparison among feasible products. This is, basically, a virtual prototyping methodology of the complete system, ideal in the production of high quality competitive electroplating products.

Cross Cultural Instruction: An Instructional Design Case

In an authentic example of linking design and development with learning and performance, an international real estate development firm defined a problem; implementing a cleaning system in the largest mall in the world with a cross-cultural unskilled work force in Dubai, UAE. Partnering with a university instructional design team employing a rapid prototyping methodology and the constructivist ID approach, Layers of Negotiation Model, a comprehensive curriculum was designed. This article describes the project background, initial design, the ID team's work in Dubai, illustrates the product, and summarizes the design experience.KeywordsCross-cultural instructional design, design-based research, job aids, constructivist ID environments, layers of negotiation model, rapid prototyping, project management