prototyping, digital model, physical model, smart building envelope, and design process
Abstract
In this study, a design methodology based on prototyping is proposed. This design methodology is intended to enhance the functionality of the test, differentiating it from the prototyping that is being conducted in conventional architectural design projects. The objective of this study is to explore reference cases that enable designers to maximize the utilization of both digital models and physical models that have been currently used in architectural designs. Also, it is to explore the complementary roles and effects of digital models and physical models. Smart Building Envelopes (SBEs) are one of challenging topics in architectural design and requires innovative design process included tests and risk management. A conceptual prototyping-based model considering the topic is applied to the design studio (education environment in university). Designing SBEs is not difficult to conceive ideas, but it is impossible to “implement” using the conventional design method. Implementing SBEs requires to strengthen validities and improve responsibilities of ideas in the stages of architectural designs, with cutting-edge technologies and smart materials. The design methodology enables designers (represented by students) to apply materials and manufacturing methods using digital models (parametric design, simulation, BIM) and physical models, rather than representing vanity images that are considered simple science fiction.
This article presents a novel methodology to design swash plate type axial piston machines based on computationally based approach. The methodology focuses on the design of the main lubricating interfaces present in a swash plate type unit: the cylinder block/valve plate, the piston/cylinder, and the slipper/swash plate interface. These interfaces determine the behavior of the machine in term of energy efficiency and durability. The proposed method couples for the first time the numerical models developed at the authors’ research center for each separated tribological interface in a single optimization framework. The paper details the optimization procedure, the geometry, and material considered for each part. A physical prototype was also built and tested from the optimal results found from the numerical model. Tests were performed at the authors’ lab, confirming the validity of the proposed method.
Eduardo Zafra, Sergio Vazquez, Hipolito Guzman Miranda, Juan A. Sanchez, Abraham Marquez, Jose I. Leon, and Leopoldo G. Franquelo
Energies, 2020, 13, 5, 1.
Subjects
field-programmable gate array (FPGA), field-programmable system-on-chip (FPSoC), finite control set (FCS), model predictive control (MPC), and voltage source inverter (VSI)
Abstract
This work describes an efficient implementation in terms of computation time and resource usage in a Field-Programmable System-On-Chip (FPSoC) of a Finite Control Set Model Predictive Control (FCS-MPC) algorithm. As an example, the FCS-MPC implementation is used for the current reference tracking of a two-level three-phase power converter. The proposed solution is an enabler for using both complex control algorithms and digital controllers for high switching frequency semiconductor technologies. An original HW/SW (hardware and software) system architecture for an FPSoC is designed to take advantage of a modern operating system, while removing time uncertainty in real-time software tasks, and exploiting dedicated FPGA fabric for the most complex computations. In addition, two different architectures for the FPGA-implemented functionality are proposed and compared in order to study the area-speed trade-off. Experimental results show the feasibility of the proposed implementation, which achieves a speed hundreds of times faster than the conventional Digital Signal Processor (DSP)-based control platform.
Vehicle design, components selection, vehicle assembling, costs analysis, and sustainability
Abstract
Hybrid vehicles currently represent a compromise between the maturity of conventional vehicles and the low consumption and attention to environmental issues of electric vehicles. This article analyzes the feasibility of a hybrid series vehicle where the heat engine is replaced by a micro gas turbine. In the continuous generation of electric current, it has numerous advantages compared to an internal combustion engine and the purpose of the article is to verify whether these advantages also apply to traction in a hybrid vehicle. The model will be a city car as problems in urban environments of pollution and optimization of consumption are more revealing. After defining performance requirements, the main components are sized and then selected from the catalog, paying attention in the search for a compromise between performance, space constraints, and costs. The Advisor software will then be used to simulate the configuration in both urban and suburban cycles, paying attention to performance, the state of charge of the battery, the operating points of the microturbine, the input and output energy for each element, and fuel consumption. Then, we analyze the level of pollutant emissions to verify that they are lower than the values set by European legislation, specifically the EURO 6 standard. Finally, the total life cycle costs of the car are analyzed as the sum of the purchase cost, operating costs, and maintenance costs to verify the competitiveness of the configuration in the current market. The car was then compared with the Toyota Yaris Hybrid in terms of performance, fuel consumption, emissions, and costs to highlight advantages and disadvantages.
Pedro P. C. Bhagubai, João G. Sarrico, João F. P. Fernandes, and P. J. Costa Branco
Energies, 2020, 13, 10, 1.
Subjects
electromagnetic modeling, multi-objective optimization, permanent magnet, and synchronous motor
Abstract
A high-performance 20 kW, 20 Nm, 8000 rpm, spoke-type interior permanent magnet motor to be integrated into a FormulaStudent electric car’s powertrain has been designed to meet demanding performance requirements for its driving cycle. This paper describes key steps in the design optimization, analysis, fabrication, and testing of this machine. Design optimization used the non-dominated sorting genetic algorithm II (NSGA-II) coupled with a hybrid analytical/finite element model to reduce the computational time, achieving a torque and efficiency of 20 Nm and 98.6%, respectively. A prototype has been constructed. The final motor design has been tested, where experimental nominal torque and efficiency have reached 18.2 Nm and 90%, respectively. Design challenges regarding the manufacturing are presented, justified, and discussed in detail. Test results were conducted to evaluate reliability and motor temperatures with and without water refrigeration at nominal current. Despite those adjustments in the optimized design, one shows that the impact on the car’s lap time was low, going from 77.3 s for the ideal optimized motor to 78.9 s for the prototyped motor.
Countries where spontaneous use of Bitcoin have emerged to circumvent Governments: China, Argentina ..., Agent-based modeling, and Microsimulation models
Abstract
Cryptomoney (Bitcoin, Ethereum ...) are uncontrolled by central authorities, have no monetary or interest rate policies attached to them. While their mass is not significant, they provide enormous potential as speculative underlier. Agents dealing with them could be a vast, unchecked public, and their expectations and optimization on future values may be very far from rationality. The objective of this paper is to offer a framework to simulate the possible outcome of interacting independent, heterogenous classes of consumers, banks, governments, goods manufacturers, with an autonomous generation of cryptomoney. Starting from a classic IS-monetary policy and bank credit framework, a flow model is derived, and independent agents are created. They have independent optimization processes and visibility scopes. They act in uncertainty and with partially guessed variables. The model is driven through a 40-50 time frames with a DSGE like logic to explore transitory regimes. Excel VBA is used for the core prototype, then the model is finally rewritten in Python - speculative bubbles may form around the cryptocurrency used. The model zooms on what other parameters in the behaviour equations (e.g psychological discount rate, propensity of consumption, preference for liquidity ...) may dampen or heighten speculations. - speculators are endowed with a specific reinforced learning mechanism, TD-Learning. The model studies the optimum time intervals for enhancing or forgetting the learning effect in speculators.
Systems Research and Behavioral Science, 2019, 36, 6, 835.
Abstract
In almost all areas of the industry and more generally in the sector of development of manufacturing products, the realization of the product passes through several successive stages going from the design to the realization of the product. The most critical phase is prototyping because it is at this point that usually the most important decisions are made. In several sectors this step is very expensive, and in any case, the prototype undergoes several modifications and requires several validations before it is definitive for the transition to production. The prototype must generally constitute a model of the product that has all or part of the technical qualities and operating characteristics that must appear in the final product, to demonstrate or affirm the validity of the concept and thus its final validation, which increases the overall cost of the prototyping phase. In the vast majority of prototyping devices available for the moment, be it by additive or subtractive process, the realization of the prototype requires a lot of time, and once the prototype is made, it can only be modified by destructive techniques because the materials used are frozen and do not allow easy reuse. This study proposes a device for the prototyping of product, allowing a modification of the geometry of the prototype by means of a deformable composite membrane with shape memory, reusable and programmable. The device in question consists of a flexible composite membrane whose matrix is a flexible polymer, and the reinforcement is a shape‐memory alloy fibre and rubber effect, having a given electrical resistance. These shape memory fibres are woven in such a way as to ensure deformations in the direction normal to the plane of the membrane by injecting the current into each fibre. This is ensured by a cross weave allowing the control of the direction of the overall deformation through the deformation specific to each fibre. In this research work, we present the results of the modelling and simulation of the behaviour of a composite membrane with shape memory.
Amruta V. Kulkarni, Weiqiang Chen, and Ali M. Bazzi
Energies, 2016, 9, 7, 1.
Subjects
rapid prototyping, design methodology, DC-DC converters, user centered design, user interface, and design optimization
Abstract
In this paper, power loss and cost models of power electronic converters based on converter ratings and datasheet information are presented. These models aid in creating rapid prototypes which facilitate the component selection process. Through rapid prototyping, users can estimate power loss and cost which are essential in design decisions. The proposed approach treats main power electronic components of a converter as building blocks that can be arranged to obtain multiple topologies to facilitate rapid prototyping. In order to get system-level power loss and cost models, two processes are implemented. The first process automatically provides minimum power loss or cost estimates and identifies components for specific applications and ratings; the second process estimates power losses and costs of each component of interest as well as the whole system. Two examples are used to illustrate the proposed approaches—boost and buck converters in continuous conduction mode. Achieved cost and loss estimates are over 93% accurate when compared to measured losses and real cost data. This research presents derivations of the proposed models, experimental validation of the models and demonstration of a user friendly interface that integrates all the models. Tools presented in this paper are expected to be very useful for practicing engineers, designers, and researchers, and are flexible and adaptable with changing or new technologies and varying component prices.
András Poppe, Gábor Farkas, Lajos Gaál, Gusztáv Hantos, János Hegedüs, and Márta Rencz
Energies, 2019, 12, 10, 1.
Subjects
light emitting diodes, power LEDs, multi-domain modelling, and LED luminaire design
Abstract
This paper presents our approaches to chip level multi-domain LED (light emitting diode) modelling, targeting luminaire design in the Industry 4.0 era, to support virtual prototyping of LED luminaires through luminaire level multi-domain simulations. The primary goal of such virtual prototypes is to predict the light output characteristics of LED luminaires under different operating conditions. The key component in such digital twins of a luminaire is an appropriate multi-domain model for packaged LED devices that captures the electrical, thermal, and light output characteristics and their mutual dependence simultaneously and consistently. We developed two such models with this goal in mind that are presented in detail in this paper. The first model is a semi analytical, quasi black-box model that can be implemented on the basis of the built-in diode models of spice-like circuit simulators and a few added controlled sources. Our second presented model is derived from the physics of the operation of today’s power LEDs realized with multiple quantum well heterojunction structures. Both models have been implemented in the form of visual basic macros as well as circuit models suitable for usual spice circuit simulators. The primary test bench for the two circuit models was an LTspice simulation environment. Then, to support the design of different demonstrator luminaires of the Delphi4LED project, a spreadsheet application was developed, which ensured seamless integration of the two models with additional models representing the LED chips’ thermal environment in a luminaire. The usability of our proposed models is demonstrated by real design case studies during which simulated light output characteristics (such as hot lumens) were confirmed by luminaire level physical tests.
Production and Operations Management, 2018, 27, 3, 496.
Abstract
Prototyping allows firms to evaluate the technical feasibility of alternative product designs and to better estimate their costs. We study a collaborative prototyping scenario in which a manufacturer involves a supplier in the prototyping process by letting the supplier make detailed design choices for critical components and provide prototypes for testing. While the supplier can obtain private information about the costs, the manufacturer uses target costing to gain control over the design choice. We show that involving the supplier in the prototyping process has an important influence on the manufacturer's optimal decisions. The collaboration results in information asymmetry, which makes parallel prototyping less attractive and potentially reverses the optimal testing sequence under sequential prototyping: It may be optimal to test designs in increasing order of attractiveness to avoid that the supplier does not release technically and economically feasible prototypes for strategic reasons. We also find that the classical target costing approaches (cost†and market†based) need to be adjusted in the presence of alternative designs: Due to the strategic behavior of suppliers, it is not always optimal to provide identical target costs for designs with similar cost and performance estimates, nor to provide different target costs for dissimilar designs. Furthermore, the timing is important: While committing upfront to carefully chosen target costs reduces the supplier's strategic behavior, in some circumstances, the manufacturer can take advantage of this behavior by remaining flexible and specifying the second prototype's target costs later.
Dante Ruiz-Robles, Vicente Venegas-Rebollar, Adolfo Anaya-Ruiz, Edgar L. Moreno-Goytia, and Juan R. Rodríguez-Rodríguez
Energies, 2018, 11, 8, 1.
Subjects
medium frequency transformer, design methodology, nanocrystalline core, and DAB
Abstract
Medium frequency transformers (MFTs) are a key component of DC–DC dual active bridge (DAB)-type converters. These technologies are becoming a quintessential part of renewable energy solutions, such as photovoltaic systems and wind energy power plants, as well as in modern power grid interfaces functioning as solid-state transformers in smart-grid environments. The weight and physical dimensions of an MFT are key data for the design of these devices. The size of an MFT is reduced by increasing its operating frequency. This reduction implicates higher power density through the transformer windings, as well as other design requirements distinct to those used for conventional 60/50 Hz transformers; therefore, new MFT design procedures are needed. This paper introduces a novel methodology for designing MFTs, using nanocrystalline cores, and tests it using an MFT–DAB lab prototype. Different to other MFT design procedures, this new design approach uses a modified version of the area-product technique, which consists of smartly modifying the core losses computation, and includes nanocrystalline cores. The core losses computation is supported by a full analysis of the dispersion inductance. For purposes of validation, a model MFT connected to a DAB converter is simulated in Matlab-Simulink (The MathWorks, v2014a, Mexico City, Mexico). In addition, a MFT–DAB lab prototype (1 kVA at 5 kHz) is implemented to experimentally probe further the validity of the methodology just proposed. These results demonstrate that the analytic calculations results match those obtained from simulations and lab experiments. In all cases, the efficiency of the MFT is greater than 99%.