Computer-aided Design Environment Research Articles

Longitudinal clustering of students’ self-regulated learning behaviors in engineering design

It is vital to develop an understanding of students' self-regulatory processes in the domains of STEM (Science, Technology, Engineering, and Mathematics) for the quality delivery of STEM education. However, most studies have followed a variable-centered approach, leaving open the question of how specific SRL (Self-regulated Learning) behaviors group within individual learners. Furthermore, little is known about how students' SRL profiles unfold over time in STEM education, specifically in the context of engineering design. In this study, we examined the change of students’ SRL profiles over time as 108 middle school students designed green buildings in a simulation-based computer-aided design (CAD) environment. We identified three distinct SRL profiles using a longitudinal clustering approach: reflective-oriented, adaptive, and minimally self-regulated learners. In addition, we found that students with different profile memberships differed significantly in their design performance. Specifically, adaptive self-regulated learners outperformed minimally self-regulated learners on design completeness, whereas reflective-oriented self-regulated learners demonstrated higher design efficiency than minimally self-regulated learners. This study provides researchers with both theoretical and methodological insights concerning SRL dynamics. Findings from this research also inform practitioners about the design of adaptive interventions.

A Method to Investigate Mechanical Properties of Lattice Structures for Additive Manufacturing

The manufacturing technologies have undergone significant innovation at the beginning of this century from the development of science and technology. One of the most important inventions in manufacturing technologies is the creation of additive manufacturing technology. Additive manufacturing technologies allow building of a 3D object by adding ultra-thin layers of 2D cross-sectional slices of materials upon these previous layers. The most crucial effectiveness of additive manufacturing technologies is to fabricate the complex geometry of products. As a result, the lattice structure is used extensively in industrial product design to minimize usage of materials and reduce the weight of products. However, the simulation to investigate the mechanical properties of the lattice structure in the design space of a product has many issues such as calculation time, memory-consuming, etc. Thus, the paper presents a new method to automatically generate a geometric model of the lattice structure in a computer-aided design environment. This model will be used to make a simulation using the finite element method analysis to investigate the mechanical properties of each configuration of the lattice structure.

System-level co-simulation for embedded systems

The technological revolution affects the growth of systems in terms of functionality and complexity. Industries of embedded systems become increasingly an area of interest for researchers to develop Computer-Aided Design (CAD) environments to support at the same time the complexity in terms of different components and functionalities in terms of application programming interface and libraries. Mainly, CAD tools based on multi-level co-simulation are challenged by the time-to-market constraint. As known, the behavior description at a higher level provides a speedy simulation, but it suffers from bad accuracy. Therefore, describing a customized model for a system behavior with sufficient functional details at an earlier stage of modeling is a great challenge to researchers. As an attempt to overcome the last challenge, this paper presents a co-simulation model based on a synchronization methodology to ensure the verification between the conceptual level and the functional level. The proposed system-level co-simulation model is implemented to interfaces to provide the switch context in the case of the Arena and the Simulink/Matlab environments. The evaluation was performed by using two case studies with different domains to prove the effectiveness of the proposed system-level co-simulation interfaces.

Optimized Data Exchange Process between Design and Production Engineering

Growing vehicle variant diversity, legal requirements to reduce fleet CO2 emissions and innovations in the area of drive train technologies, coupled with the increasing pressure to cut costs, pose new challenges for parties in the automotive sector. An implementation of optimized development and production processes supports the effective handling of these challenges. One important aspect includes engineering efficiency improvement by optimizing the entire automotive bodywork development process and the involved data management. Research activities focus on the data exchange processes between design, simulation and production engineering within various CAx environments. This concerns constantly changing boundary conditions and requirements in the area of automotive body development, including but not limited to the introduction of new materials and material combinations and new types of joining technologies. From the viewpoint of an automotive engineering supplier, additional challenges caused by different customer-related development environments have to be considered. To overcome these challenges, various data exchange strategies between OEMs (Original Equipment Manufacturer), automotive suppliers and the use of different data management tools need to be investigated. In this context, the paper presents an approach of an optimized data exchange process of CAD-based data between different CAD (Computer-Aided Design) and CAM (Computer-Aided Manufacturing) environments that supports the entire body development, including data provision for manufacturing engineering. In addition, an optimization of data exchange processes saves development costs and improves the product quality.

Modeling Framework for a Consistent Integration of Geometry Knowledge During Conceptual Design

This paper proposes a modeling framework for a consistent geometrical data link between a system model and a spatial architecture modeling in a 3D computer-aided design (CAD) environment, with a model-based system engineering (MBSE) approach. Our approach, focused on the conceptual design stage, for the evaluation of 3D architecture under physical constraints, aims at improving the system design by ensuring data consistency during collaborative design. This model transformation platform will ensure a seamless geometrical consistency and traceability from the requirements to the further design stages. The theoretical formalization of our approach presents a consistent integration of geometry knowledge all along the conceptual design. Then, the corresponding modeling platform implementation between the developed system modeling language (SysML) geometrical extension and a 3D CAD tool is described before detailing an application on a conveyor case study.

BIM-Based Facility management for water treatment plants using laser scanning

Abstract Lack of maintenance information pertaining to water treatment plant equipment may lead to many problems within the treatment system and affect its performance. A framework for using three-dimensional laser scanning to obtain equipment maintenance information for water treatment plants is presented. The framework core phase involves automation of information exchange in a three-dimensional computer-aided design (CAD) environment as the foundation for adopting a Building Information Modeling (BIM) approach. The framework supports the concepts of BIM-based facility management through the essential task of equipment information clustering according to maintenance intervals. Clustering according to daily, weekly, monthly, and annual maintenance plans are identified with potential applicability for additional extentions. Finally, a case study illustrates the benefits of using laser scanning technology in facility management.

Weak imposition of constraints for structural membranes in transient geometrically nonlinear isogeometric analysis on multipatch surfaces

Membranes have been extensively used for the design of architectural and general structural models due to their low cost and high load carrying capacity. Traditionally such models were discretized using the standard low order Finite Element Method (FEM) which typically results in a compromised description of the geometry. However, the accurate geometric description of membrane structures is essential as for instance bifurcation points in geometrically nonlinear analysis may be inaccurately predicted when the geometric description of the model is not accurate enough. Moreover, the design of membrane structures typically requires several cycles of form-finding and subsequent structural analysis under various loads which can benefit from a direct connection to the Computer-Aided Design (CAD) environment using its exact geometric description. In this contribution, the form-finding analysis using the Updated Reference Strategy (URS) and the geometrically nonlinear transient analysis of membranes is extended to Isogeometric Analysis (IGA) on multipatch surfaces with Non-Uniform Rational B-Splines (NURBS). As typical in IGA for real CAD geometries, multiple patches with non-matching parametrizations are considered and therefore the continuity of the solution field along with the application of weak Dirichlet boundary conditions need to be addressed. Thus, four different constraint enforcement methods are elaborated and compared, namely, the Penalty, the Lagrange Multipliers, the augmented Lagrange Multipliers and a Nitsche-type method. For the latter method, a solution dependent stabilization approach is employed in order to render the Nitsche-type method coercive. All methods are elaborated and systematically compared in both form-finding analysis, whenever necessary, and subsequently in geometrically nonlinear transient analysis. It should be noted that the Nitsche-type method is more computationally demanding amongst these methods due to the additional nonlinear terms. However, the results suggest that the Nitsche-type method is advantageous for these kinds of problems as no parameter or discretization other than the isogeometric discretization within each patch needs to be specified prior to the analysis.

An Electrooptothermal-Coupled Circuit-Level Model for VCSELs Under Pulsed Condition

In this paper, a circuit-level model for accurately calculating vertical-cavity surface-emitting laser's (VCSEL) response under pulsed working condition is implemented in the advanced design system computer-aided design environment. New normalization method and thermal leakage current expression are proposed to rate equation to improve numerical convergence of the model's output part, which is critical for pulsed working condition. A self-consistent decoupling method is applied to include the self-heating effects in both input and output parts of the model for getting the accurate waveforms of input current and output light power under pulsed driving conditions. The model's input part is similar to standard SPICE model for p-n junction diode, and is convenient for extracting model parameters to match the device's input impedance profile. A real device's model parameters are extracted, and its voltage–current–light power ( V – I – P ) curves, small-signal transfer function, and transient response under pulsed drive condition are calculated to demonstrate the model's calculation capability. The proposed model is well applicable for designing a high-power electromagnetic sensor including VCSEL and other high-frequency devices.

On the microwave noise figure measurement: A virtual approach for mismatched devices

In this paper, the challenging task of the 50 Ω noise figure measurement of mismatched devices has been addressed by tailoring a microwave virtual test-bench in a computer-aided design environment. The effects of the real measurement chain on the device noise figure as well as that of the noise figure meter and noise source have been taken into account by characterizing and modeling every component. The effectiveness of the simulation has been proven by comparing the virtual test-bench noise figure with that calculated from the measured scattering and noise parameters of a 0.15 µm pHEMT in the 2–26 GHz frequency range. Hereby, all the processes involved in the 50 Ω noise figure measurements of mismatched devices have been presented by a visual and user-friendly interface. By this original approach, a fast evaluation of each component role in the measurement chain can be accomplished. A performance estimation of the system can be performed and updated in a simple way whenever a component is replaced. Finally, since every step of the procedure has been disclosed and extensively clarified, it might be used as a training tool for microwave engineers.

An analytical model for cutter-workpiece engagement calculation in ball-end finish milling of doubly curved surfaces

This paper presents a new analytical model for calculating the cutter-workpiece engagement (CWE) boundaries in the ball-end finish milling process of curved surfaces. To this end, first, a quadratic mathematical representation considering the principal curvatures of the surface is employed to locally describe the workpiece surface around the instantaneous cutting region. This description, then, is utilized to find the intersection curves of the tool rotary and workpiece surfaces in three ball-end milling modes including slotting, first cutting, and following cutting. Through comparison studies, the model predictions are verified by the corresponding results obtained via solid modeling in computer-aided design (CAD) environment. The agreement between the results indicates that the model can accurately calculate the CWE boundaries in the ball-end milling of all inclined, convex, concave, and saddle surfaces. Good performance of the model is also demonstrated by comparing the computation time of the model with that of the z-map method. Finally, parametric studies are performed to reveal the effects of surface curvatures and cutting depth on the CWE region. The results show that the CWE is more affected by the surface curvatures as the cutting depth decreases, especially at the concave and saddle regions of the workpiece surface. The proposed analytical model is capable of calculating the CWE boundaries in both three-axis and five-axis milling processes, and there is no need to neither use any numerical solutions nor update the in-process workpiece geometry during the simulation of the CWE boundaries.

Learning as Making: Using 3D computer‐aided design to enhance the learning of shape and space in STEM‐integrated ways

AbstractThe recent and popular “Maker” movement worldwide has revived conversations about creativity, hands‐on “Making,” arts and design, humans with tools and digital experiences beyond the flat‐screen. However, such conversation mainly revolved outside the realm of formal education. This article presents two learning tasks, one in upper primary (age 10–11) and one in lower secondary (age 12–13), which integrate “Making” and 3D computer‐aided design (CAD), thereby facilitating Science, Technology, Engineering, and Mathematics (STEM) learning in mathematics classrooms. By adopting a design‐based research methodology, we examine students' mathematics learning with respect to dissecting and forming 2D shapes and volume of composite solids with the use of 3D CAD and the kinds of integrated STEM learning practices they demonstrated in the activities. Qualitative data were collected in the form of videos of the students' communication and screenshots of their initial and final designs as they engaged with the 3D CAD environment, as well as students' written reflections and teachers' lesson analysis. Results showed that the students used 3D CAD to develop spatial skills and to achieve mathematics learning far beyond using formulae and performing procedures. The learning activities also enabled an integrated STEM learning experience in productive and unobtrusive ways.

A new surface-potential-based compact model for the MoS2 field effect transistors in active matrix display applications

We present a continuous surface-potential-based compact model for molybdenum disulfide (MoS2) field effect transistors based on the multiple trapping release theory and the variable-range hopping theory. We also built contact resistance and velocity saturation models based on the analytical surface potential. This model is verified with experimental data and is able to accurately predict the temperature dependent behavior of the MoS2 field effect transistor. Our compact model is coded in Verilog-A, which can be implemented in a computer-aided design environment. Finally, we carried out an active matrix display simulation, which suggested that the proposed model can be successfully applied to circuit design.

A BIM-based automation of design and drafting for manufacturing of wood panels for modular residential buildings

ABSTRACTDesign and drafting requirements associated with modular construction exceed those of the traditional stick-built method. Man-made errors, design assumptions and onsite interpretations of the shop drawings cannot be tolerated. Therefore, building information modelling (BIM) is needed to facilitate the automation of design and drafting for manufacturing. However, high initial cost, required expertise and limitations of currently available software prevent BIM from realizing its full potentials. This research introduces a systematic methodology for automating the drafting and design for manufacturing of wood-framed panels for modular residential buildings. It utilizes 2D computer-aided design (CAD) drawings to automatically generate BIM and construction manufacturing BIM; subsequently, shop drawings for the wood-framed panels are developed according to the platform framing method. The proposed framework is incorporated into a computer application called MCMPro, which is developed using visual basic application within CAD environment. Reduced design cost, improved layout accuracy and enhanced productivity are expected advances of MCMPro.

Improving the Safety and Security of Wide-Area Cyber–Physical Systems Through a Resource-Aware, Service-Oriented Development Methodology

This paper presents a service-oriented development methodology for wide-area cyber–physical systems (CPS) such as smart grid and vehicular networks. Unlike the traditional task-based development approach from the domains of automotive and avionics, the proposed service-oriented development methodology inherently enables disruption-free incremental system deployment and reconfiguration that are fundamental requirements for handling the “always-online” nature of emerging wide-area CPS application domains such as smart grid and vehicular networks. The proposed service-oriented CPS development methodology extends the traditional service-oriented computing (SOC) paradigm for handling hard real-time CPS aspects by introducing resource-aware service deployment and quality-of-service (QoS)-aware service operation phases. The proposed CPS development methodology also supports a streamlined formal interface between the traditional computer-aided feedback controller design environments and SOC paradigm. The paper utilizes a simulation-based smart grid case study to illustrate the advantages of the proposed methodology for developing wide-area cyber–physical systems with improved safety and security characteristics. The paper also identifies a set of technological requirements for the proposed service-oriented CPS development methodology that should guide future research in this area.

Hybrid state transactional database for product lifecycle management features in a multi-engineer synchronous heterogeneous CAD environment

ABSTRACTAs interoperability between Computer Aided Design (CAD) systems becomes a possibility, a need arises for a way for the Neutral Parametric Canonical Form (NPCF), as designed at the BYU Site of the NSF Center for e-Design, to be integrated with Product Lifecycle Management (PLM). The only method currently available to users to sync with a PLM system at this time would be to choose one CAD system and create files based off of the NPCF data then save those part files in the PLM system. This database expansion to the NPCF allows the NPCF to hold the entire part history as well as enable future work revision history and configuration management. Enforcing referential integrity within the database allows for part data to never get corrupted and the NPCF allows any CAD system with the appropriate plug-ins to read the uncorrupted data.

Exploring the use of 3D Computer-Aided Design and 3D Printing for STEAM Learning in Mathematics

This snapshot explores the use of 3D computer-aided design (CAD) and 3D printing for teaching about the volume of solids in junior secondary mathematics classrooms. An open-ended class project involving the design (in a CAD environment), calculation (on paper) and printing of 3D objects (using a 3D printer) was offered to students aged 13 to 15 in three mathematics classes. Qualitative data was collected in the form of video recordings of the students’ communications (while working both with and away from the computers), and in the form of students’ calculations and written reflections (as part of their projects). These observations revealed that the students developed a discourse about volume of composite solids that was inextricably linked to the 3D CAD environment, and that the 3D printing technology enabled an integrated STEAM learning experience for the students. Implications about task design and extensions are discussed in relation to STEAM learning.

A comprehensive computational multidisciplinary design optimization approach for a tidal power plant turbine

Multidisciplinary design optimization has become a powerful technique to facilitate continuous improvement of complex and multidisciplinary products. Parametric modeling is an essential part with tremendous impact on the flexibility and robustness of multidisciplinary design optimization. This article investigates the effect of relational and non-relational parameterization techniques on the robustness and flexibility of the conceptual design of a multidisciplinary product. Bench marking between relational and non-relational parameterization and their effect on flexibility and robustness indicate that the relational parameterization is an efficient method in the multidisciplinary design optimization process. The inherent properties of the method contribute to an efficient parametric modeling with improved communication between different disciplines. This enhances the performance of the multidisciplinary design optimization process and allows a more flexible and robust design. The considered disciplines are computer-aided design, computational fluid dynamics, finite element analysis, and dynamic simulation. A high-fidelity geometry created in a computer-aided design environment is computer-aided design centric approach and later used in computational fluid dynamics, finite element analysis for a better understanding of the product as it leads to precise outcomes. The proposed approach is implemented for the conceptual design of a novel product, a tidal power plant developed by Minesto AB using a multidisciplinary design optimization process.

FROM OSS CAD TO BIM FOR CULTURAL HERITAGE DIGITAL REPRESENTATION

Abstract. The paper illustrates the use of open source Computer-aided design (CAD) environments in order to develop Building Information Modelling (BIM) tools able to manage 3D models in the field of cultural heritage. Nowadays, the development of Free and Open Source Software (FOSS) has been rapidly growing and their use tends to be consolidated. Although BIM technology is widely known and used, there is a lack of integrated open source platforms able to support all stages of Historic Building Information Modelling (HBIM) processes. The present research aims to use a FOSS CAD environment in order to develop BIM plug-ins which will be able to import and edit digital representations of cultural heritage models derived by photogrammetric methods.

Explicit function-based design modelling methodology with features

ABSTRACTThis paper presents a generic functional design modelling methodology applied in the computer-aided design (CAD) environment to associate functional considerations and physical models of the design. Function concept modelling represents the engineering design purposes of the product elements and is usually considered to be interdependent from the detailed geometric solutions. Although CAD is prevailing in modelling geometry of the design artefacts, functional considerations, or design intents, are often not represented systematically and explicitly. The gaps between functional and geometrical representations of the design models require an extensive research to unveil their associations and interactions. Functional feature, and the corresponding semantic representation with the built-in mechanisms, is proposed in this paper to support a CAD methodology that models the interrelations between functional and physical considerations of the design and drives the design through functional perspective. geometry features are used as functional concept carriers with certain geometries to link functional design considerations in the detailed design model. A case study of a designed product that is used in the oil extraction process from oil sands in Canada is presented to demonstrate the feasibility of the proposed methodology.

Computer aided weld seam tracking approach

PurposeThis paper aims to automate the welding operation that motion control, sensor integration and coordination with the welding power source. Therefore, there is a need for sophisticated technologies to control precisely the process in terms of positioning the welding torch, and controlling the welding parameters through the use of correct devices which are aided by appropriate control tools and techniques.Design/methodology/approachA new seam tracking methodology, named sewing technique, has been introduced for the welded joints available in computer-aided design (CAD) environment. This methodology gives the seam path by drawing a line through the adjacent centroids of curve fitted in the weld joint volume. Obtained geometric path and kinematic constraints are given as input to the modeled robot for performing welding operation followed by desired trajectory.FindingsIn this investigation, a novel and efficient weld seam technique has been developed to produce uniform welded joints. The key feature of this approach is that the initial and end positions of the weld seams can be obtained easily. Because of this, the robot can be controlled flexibly during welding operation.Originality/valueThis investigation deals with the development of an automated seam tracking methodology for the welded joints available in CAD environment. Validation of the developed methodology has been done through simulation results while performing welding operations for different weld profiles.