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.
Iglesias, P., Izquierdo, P., Yañez, P., Vilán, J.A., Arias, A., Segade, A., and Casarejos, E.
Instrumentation viewpoint; 2018: Núm.: 20
It is at least two decades since the conventional robotic manipulators have become a common manufacturing tool for different industries, from automotive to pharmaceutical. The advances in manipulators and sensors have given robots the opportunity to become useful for more and more applications. Engineers have taken advantage of the extra mobility of the advanced robots to make them work in constrained environments, ranging from limited joint motions for redundant manipulators to obstacles in the way of mobile (ground, marine, and aerial) robots . However, the incorporation some of these abilities and capacities that are already being used in land, have not made their way to the sea domain. This Abstract describes the project consisting in the design, development and manufacture of a prototype manipulator arm for ROVs introducing innovative fabrication technologies. The work has been done collaboratively among ACSM Maritime Agency SL, CIMA Group and the University of Vigo.
Ferrari, A., Novara, C., Paolucci, E., Vento, O., Violante, M., and Zhang, T.
Applied Energy, 2018, 232, C, 358.
Fuel injection system, Diesel engine, Injected mass control, and Rapid prototyping hardware
A closed-loop strategy that is capable of controlling the fuel injected mass in the combustion chamber of a Common Rail diesel engine has been set up. The pressure time histories measured along the rail-to-injector pipe have been used to evaluate the instantaneous mass flow-rate entering the injector. This flow-rate has then been integrated between two time instants, and the thus calculated fuel mass has resulted to correlate well with the injected mass.
András Poppe, Gábor Farkas, Lajos Gaál, Gusztáv Hantos, János Hegedüs, and Márta Rencz
Energies, 2019, 12, 10, 1.
light emitting diodes, power LEDs, multi-domain modelling, and LED luminaire design
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.
Abstract This paper describes a Grid-like Material Transportation Network (GMTN) in which several heterogeneous means of transportation (Automated Guided Vehicles (AGVs), hoists, lifts, etc.) interact with each other via common shared workstations to provide a variety of demand-responsive material handling operations. Different material handling transport modes provide movement of workpieces between workstations along their manufacturing routes in the GMTN and they can be seen as processes realized with synergic utilization of various local periodically acting unimodal processes. The main contribution of this research is the solution of a constraint satisfaction problem addressing AGVs fleet match-up scheduling subject to GMTN and fuzzy operation time constraints. In the presented case both production rate (production takt) and operations execution time are described by imprecise (fuzzy) data. In other words, the research’s objective concerns assessing grid-like networks of periodically acting local transportation modes from the perspective of possible mass-customized oriented requirements imposed on scheduling of multimodal flows of jobs assigned to certain technological routes passing through common shared workstations.
Amruta V. Kulkarni, Weiqiang Chen, and Ali M. Bazzi
Energies, 2016, 9, 7, 1.
rapid prototyping, design methodology, DC-DC converters, user centered design, user interface, and design optimization
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.
Technological Forecasting and Social Change, 2016, 102, C, 214.
3D printing, Business models, Innovation, Rapid prototyping, Rapid tooling, Direct Digital manufacturing, Home fabrication, Value creation, and Value capture
There is a growing consensus that 3D printing technologies will be one of the next major technological revolutions. While a lot of work has already been carried out as to what these technologies will bring in terms of product and process innovation, little has been done on their impact on business models and business model innovation. Yet, history has shown that technological revolution without adequate business model evolution is a pitfall for many businesses. In the case of 3D printing, the matter is further complicated by the fact that adoption of these technologies has occurred in four successive phases (rapid prototyping, rapid tooling, digital manufacturing, home fabrication) that correspond to a different level of involvement of 3D printing in the production process. This article investigates the effect of each phase on the key business model components. While the impact of rapid prototyping and rapid tooling is found to be limited in extent, direct manufacturing and, even more so, home fabrication have the potential to be highly disruptive. While much more value can be created, capturing value can become extremely challenging. Hence, finding a suitable business model is critical. To this respect, this article shows that 3D printing technologies have the potential to change the way business model innovation is carried out, by enabling adaptive business models and by bringing the ‘rapid prototyping’ paradigm to business model innovation itself.
Production and Operations Management, 2018, 27, 3, 496.
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 (costâ€ and marketâ€ 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.