Particle Swarm Optimisation Based 3D Reconstruction of Sketched Line Drawings

The purpose of this paper is to demonstrate the application of particle swarm optimisation to line drawings reconstruction. The paper’s new contribution is the application of swarm intelligence in dealing with machine perception of sketch-based modelling interfaces. Traditional descent or gradient- based optimisation algorithms are not always practical in this context because of the severe numerical noise and ill-defined objective function of the optimisation-based reconstruction problem Our results point to particle swarm optimisation as a promising alternative.This work was partially supported by Universitat Jaume I (Plan 2002 de promoció de la investigació a l’UJI, Project P1-1B2002-08, entitled “From sketch to model: new user interfaces for CAD systems”)

Explicit Communication of Geometric Design Intent in CAD: Evaluating Annotated Models in the Context of Reusability

CAD model reusability is largely determined by a proper communication of design intent, which is usually expressed implicitly within the model. Recent studies have suggested the use of 3D annotations as a method to embed design information in the model’s geometry and make part of the design knowledge explicitly available. In this paper, we evaluate the effectiveness of this method and analyze its impact in model alteration tasks. Our goal is to determine whether annotated models provide significant benefits when performing activities that require a direct manipulation of the geometry. We present the results of a study that measured user performance in two scenarios. First, we tested whether annotations are helpful when inadequate modeling assumptions can be made by designers. Second, we evaluated annotations as tools to communicate design decisions to select the most appropriate solution to a challenge when multiple options are available. In both cases, results show statistically significant benefits of annotated models, suggesting the use of this technique as a valuable approach to improve design intent communication

Integrated modeling with Top-Down approach in subsidiary industries

This article considers how conceptual design of industrial products is supported by current CAD systems. The case of subsidiary industries, or first tier suppliers, that must simultaneously deal with different customers and CAD platforms, receive special attention. Conceptual design is critical, since the large variety of fundamental product data managed (not just geometry) would be specified, modeled and interrelated (i.e. functional relations), to both simplify and ensure correctness and efficiency of the next design phases of current design, and make them easy to reuse, modify and redesign in the future. We give an approach to introduce conceptual design through top-down methodology and integrate it with final geometry. In this context, and in order to help subsidiary industries to improve their model quality, we propose the elaboration of product-oriented modeling guidelines, or “best modeling practices”, instead of CAD-oriented modeling guidelines. The approach has been validated by testing the conceptual design tools of two commercial high-end CAD systems at use in many subsidiary automotive industries

ParSketch: a Sketch-based Interface for a 2D Parametric Geometry Editor

ParSketch is a software prototype to evaluate the usability and functionality of a sketching interface aimed at defining 2D parametric sections. Currently, ParSketch interprets strokes which can be recognized as geometry (line, arc, circle, ellipse, or composed entities that are automatically segmented into those basic entities), or graphic gestures representing constraints (dimension, parallel, perpendicular, tangent, concentric, horizontal or vertical). From the functionality point of view, ParSketch compares to current commercial parametric CAD applications, as it offers many of the features provided by such applications. A theoretical analysis of the efficiency component of usability is provided that justifies the potential capability of sketching interfaces to compete with classical WIMP applications. Finally, a usability study is presented, which makes special emphasis in the satisfaction component of usability.The Spanish Ministry of Science and Education and the European Union (Project DPI2004-01373) supported this work. It was also partially supported by Fundació Caixa Castelló-Bancaixa under the Universitat Jaume I program for Research Promotion (Project P1-1B2004-02)

On the application of model-based definition strategies to the delivery of technical training

ASME 2017 12th International Manufacturing Science and Engineering Conference (MSEC2017). June 4-8, 2017, Los Angeles, CA, USAThe application of computer technology to engineering and manufacturing domains has drastically transformed the way products and systems are designed and produced. However, a major drawback of CAD/CAM/CAE systems is the steep learning curve required to understand and master their extensive and increasingly complex set of functionalities. In this paper, we present a new approach to deliver CAD training materials that is inspired by Model-Based Definition (MDB) strategies, where annotated 3D models become the center of the training process. In our system, textual 3D annotations are connected to a Product Lifecycle Management (PLM) system to provide access to interactive video tutorials which are linked to specific features of a CAD model. As a proof of concerto to validate this approach, a plugin for a commercial CAD package was developed that enhances the functionality of standard 3D annotation mechanisms and enables users to interact with the technical training materials directly within the CAD interface. New data structures were implemented to support the connection and integration with PLM systems. A group of tutorials are described to illustrate the system architecture and implementation details

Improving Visualization Skills in Engineering Education

This article analyzes the importance of visualization skills in engineering education. It proposes a dual approach based on computer graphics applications using both Web-based graphic applications and a sketch based modeling system. It addresses the importance of spatial abilities in the context of engineering education and the available techniques for evaluating these abilities from a psychological point of view. It then reviews some Web resources conceived to help students improve their spatial abilities and presents two educational applications. Finally, it presents a pilot study carried out at La Laguna University

FOCUSING ON COMPETENCE AS A STRATEGY TO TEACH ESP IN CONTENT AND LANGUAGE INTEGRATED LEARNING CONTEXTS

The increasing spread of bilingual programs in Spanish Universities has had to face multiple worries and uncertainties over the success of Content and Language Integrated Learning (CLIL) and English-medium instruction (EMI) plans (Pavón, 2018). One of these concerns addresses the question of whether content or language should prevail in CLIL teaching. Content teachers worry about giving more importance to language than to the content they need to teach, fearing they will not be able to cope with all the compulsory content during their lectures (Doiz, Lasagabaster Pavón, 2020). CLIL developers have had to fight against the pessimistic opinions towards CLIL and its implementation in Higher Education (Cañado, 2020). The present paper aims to meet the need to move towards competence development in CLIL teaching. Approaching language and content teaching through a competence-focused perspective will help us tackle interdisciplinary as well as sustainable development goals through CLIL. A survey conducted on students of Business English courses within CLIL and Non-CLIL contexts will help us envisage the usefulness of adding non-linguistic skill development to English for Specific Purposes of teaching as a way to bridge the gap between language and content

EVM: An Educational Virtual Reality Modeling Tool; Evaluation Study with Freshman Engineering Students

[EN] Educational Virtual Modeling (EVM) is a novel VR-based application for sketching and modeling in an immersive environment designed to introduce freshman engineering students to modeling concepts and reinforce their understanding of the spatial connection between an object and its 2D projections. It was built on the Unity 3D game engine and Microsoft's Mixed Reality Toolkit (MRTK). EVM was designed to support the creation of the typical parts used in exercises in basic engineering graphics courses with a special emphasis on a fast learning curve and a simple way to provide exercises and tutorials to students. To analyze the feasibility of using EVM for this purpose, a user study was conducted with 23 freshmen and sophomore engineering students that used both EVM and Trimble SketchUp to model six parts using an axonometric view as the input. Students had no previous experience in any of the two systems. Each participant went through a brief training session and was allowed to use each tool freely for 20 min. At the end of the modeling exercises with each system, the participants rated its usability by answering the System Usability Scale (SUS) questionnaire. Additionally, they filled out a questionnaire for assessment of the system functionality. The results demonstrated a very high SUS score for EVM (M = 92.93, SD = 6.15), whereas Trimble SketchUp obtained only a mean score of 76.30 (SD = 6.69). The completion time for the modeling tasks with EVM showed its suitability for regular class use, despite the fact that it usually takes longer to complete the exercises in the system than in Trimble SketchUp. There were no statistically significant differences regarding functionality assessment. At the end of the experimental session, participants were asked to express their opinion about the systems and provide suggestions for the improvement of EVM. All participants showed a preference for EVM as a potential tool to perform exercises in the engineering graphics course.Conesa-Pastor, J.; Contero, M. (2022). EVM: An Educational Virtual Reality Modeling Tool; Evaluation Study with Freshman Engineering Students. Applied Sciences. 12(1):1-16. https://doi.org/10.3390/app1201039011612

Social tagging as a knowledge collecting strategy in the engineering design change process

This article focuses on analysing the feasibility of using social tagging as a tool for knowledge collection and retrieval in the context of the product development process (PDP). This process is a social activity that involves groups of individuals who share a common goal: to design a product . Traditional knowledge-based systems (KBS) are not very well suited to capture the tacit knowledge that is embedded in this process. Social tagging is proposed in this article as the mechanism to externalize the tacit knowledge about the best CAD modelling strategies between the design team members. This knowledge is especially relevant for the management of engineering change orders because this process is closely related to the modelling methodology used to create the three-dimensional (3D) CAD models that have to be adapted to accomplish a specific design modification. In order to analyse the feasibility of this approach, an experimental study was conducted to understand the tagging process in this context and the benefit of using this information in the modification procedure of 3D CAD models. Preliminary experimental results show that tagging represents a feasible approach to support knowledge collection on best CAD modelling practices.Alduchin-Quintero, G.; Contero, M. (2012). Social tagging as a knowledge collecting strategy in the engineering design change process. Art, Design and Communication in Higher Education. 10(2):147-162. doi:10.1386/adch.10.2.147_114716210