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

Assessing the impact of geometric design intent annotations on parametric model alteration activities

The effective representation and communication of design intent plays a crucial role in CAD model alteration activities. In history-based parametric modeling systems, design intent information is usually expressed implicitly within the model. However, there is evidence that suggests that an explicit representation can increase productivity and quality and facilitate the transferring of design knowledge throughout the different stages of the product lifecycle. In this paper, we assess the effectiveness of 3D annotations as mechanisms for explicit design intent representation and examine their impact in model alteration processes that require a direct interaction with the model s geometry. We present the results of a series of studies aimed at measuring user performance and model quality in two scenarios. First, we hypothesized that annotations are valuable tools to provide design information when inadequate modeling assumptions can be made by designers. Second, we evaluated annotations as tools to communicate design decisions 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.This work was supported by the Spanish Ministry of Economy and Competitiveness and the FEDER Funds, through the ANNOTA project (Ref. TIN2013-46036-C3-1-R).Camba, JD.; Contero, M. (2015). Assessing the impact of geometric design intent annotations on parametric model alteration activities. Computers in Industry. 71:35-45. https://doi.org/10.1016/j.compind.2015.03.006S35457

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

Implementation challenges of annotated 3D models in collaborative design environments

Recent studies in the area of collaborative design have proposed the use of 3D annotations as a tool to make design information explicitly available within the 3D model, so that different stakeholders can share information throughout the product lifecycle. Annotation practices defined by the latest digital definition standards have formalized the presentation of information and facilitated the implementation of annotation tools in CAD systems. In this paper, we review the latest studies in annotation methods and technologies and explore their expected benefits in the context of collaborative design. Next, we analyze the implementation challenges of different annotation approaches, focusing specifically on design intent annotations. An analysis of the literature suggests that the use of annotations has a positive effect on collaborative design communication as long as proper implementation practices, tools, and user interaction mechanisms are in placeCamba, J.; Contero, M.; Salvador Herranz, GM. (2014). Implementation challenges of annotated 3D models in collaborative design environments. Lecture Notes in Computer Science. 8683:222-229. doi:10.1007/978-3-319-10831-5_332222298683Katzenbach, J.R., Smith, D.K.: The Discipline of Teams. Harvard Business Review 71(2), 111–120 (2005)Campion, M.A., Medsker, G.J., Higgs, A.C.: Relations between Work Group Characteristics and Effectiveness: Implications for Designing Effective Work Groups. Personnel Psychology 46, 823–850 (1993)Chudoba, K.M., Wynn, E., Lu, M., Watson-Manheim, M.B.: How Virtual Are We? Measuring Virtuality and Understanding its Impact in a Global Organization. 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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

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”)

Parametric CAD modeling: An analysis of strategies for design reusability

CAD model quality in parametric design scenarios largely determines the level of flexibility and adaptability of a 3D model (how easy it is to alter the geometry) as well as its reusability (the ability to use existing geometry in other contexts and applications). In the context of mechanical CAD systems, the nature of the feature-based parametric modeling paradigm, which is based on parent-child interdependencies between features, allows a wide selection of approaches for creating a specific model. Despite the virtually unlimited range of possible strategies for modeling a part, only a small number of them can guarantee an appropriate internal structure which results in a truly reusable CAD model. In this paper, we present an analysis of formal CAD modeling strategies and best practices for history-based parametric design: Delphi's horizontal modeling, explicit reference modeling, and resilient modeling. Aspects considered in our study include the rationale to avoid the creation of unnecessary feature interdependencies, the sequence and selection criteria for those features, and the effects of parent/child relations on model alteration. We provide a comparative evaluation of these strategies in the form of a series of experiments using three industrial CAD models with different levels of complexity. We analyze the internal structure of the models and compare their robustness and flexibility when the geometry is modified. The results reveal significant advantages of formal modeling methodologies, particularly resilient techniques, over non-structured approaches as well as the unexpected problems of the horizontal strategy in numerous modeling situations. (C)2016 Elsevier Ltd. All rights reserved.Camba, JD.; Contero, M.; Company, P. (2016). Parametric CAD modeling: An analysis of strategies for design reusability. Computer-Aided Design. 74:18-31. doi:10.1016/j.cad.2016.01.003S18317

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)

Approach for developing coordinated rubrics to convey quality criteria in MCAD training

This paper describes an approach to convey quality-oriented strategies to CAD trainees by embedding quality criteria into rubrics so as to force CAD trainees to understand them early in their instruction. To this end, the paper analyzes how CAD quality criteria can be organized around quality dimensions and embedded into rubrics in order to enforce quality modeling during the CAD training of novice product designers. Hence, the ambit of this study is training with history-based parametric feature-based MCAD systems, although the general conclusions are believed to be adaptable to other CAD training scenarios. Furthermore, it introduces an approach based on progressive refinement, which results in an assertions map that indicates quality dimensions vs. sequence of tasks for CAD models. The map illustrates how the expand contract strategy adapts the rubrics to CAD trainee progress and assists them in comprehending the different dimensions of the rubrics. The paper also highlights lessons learned on the suitability of using separate rubrics for different tasks, the need of accurately timing the expand contract process, and on the convenience of supporting rubrics with suitable teaching, which must convey good practices and evaluation tools through rubrics. The experiments describe the different lessons learned and illustrate the suggested process for replicating our approach for further developing rubrics adapted to other scenarios.Company, P.; Contero, M.; Otey, J.; Plumed, R. (2015). Approach for developing coordinated rubrics to convey quality criteria in MCAD training. Computer-Aided Design. 63:101-117. doi:10.1016/j.cad.2014.10.001S1011176

应用扎根理论分析中等教育科技课程的组织和设置

Technology is a cross-cutting subject of knowledge and skills in the Secondary Education curriculum. Its curricular content demands constant changes due to the requirements posed by society and educational laws in Spain. This article presents a qualitative empirical research, whose methodology is based on the Grounded Theory. Although the objective of the research is broader, for reasons of space, the part corresponding to the analysis of the organizational and curricular context from the teachers' perspective is presented here. The interviewers' data collection was through observation, field diary, and audio recording of the focus groups, with the participation of 68 teachers from 17 Secondary Schools in the province of Valencia, reaching theoretical saturation in the eighth school. The fieldwork was carried out between October 2019 and February 2020. The Atlas.ti software (v.8) was used for data processing, which allowed open, axial, co-occurrence and selective coding. The conclusions of the study are: (1) the difference in infrastructure, size and ratio have an impact on educational quality, (2) institutional coordination is necessary to adapt the student transition between the different educational levels, (3) school organization together with a fragmented curriculum in core, specific and free configuration subjects, hinder the acquisition of competencies, and (4) the choice of STEM subjects depends on the gender of the students and their family environment.La asignatura Tecnología es una materia transversal de conocimientos y habilidades en el currículo de la Educación Secundaria. Su contenido curricular demanda constantes cambios debido a los requerimientos que plantea la sociedad y las leyes educativas en España. Este artículo presenta una investigación empírica de tipo cualitativo, cuya metodología se apoya en la Teoría Fundamentada. Aunque el objetivo de la investigación es más amplio, por razón de espacio, aquí se presenta la parte que corresponde al análisis del contexto organizativo y curricular desde la perspectiva de los docentes. La recopilación de datos de los entrevistadores fue mediante la observación, diario de campo, y grabación de audio de los grupos focales, con la participación de 68 docentes de 17 Institutos de Educación Secundaria de la provincia de València, alcanzando la saturación teórica en el octavo instituto. El trabajo de campo se realizó entre octubre de 2019 y febrero de 2020. Para el tratamiento de datos se empleó el software Atlas.ti (v.8) que permitió la codificación abierta, axial, coocurrencias y selectiva. Las conclusiones del estudio son: (1) la diferencia en infraestructura, tamaño y ratio repercuten en la calidad educativa, (2) la coordinación institucional es necesaria para adecuar la transición estudiantil entre los diferentes niveles educativos, (3) la organización escolar junto con un currículo fragmentado en asignaturas troncales, específicas y de libre configuración, dificultan la adquisición de competencias, y (4) la elección de asignaturas STEM depende del género de los estudiantes y de su entorno familiar.  A disciplina de Tecnologia é uma disciplina transversal de conhecimentos e competências no currículo do Ensino Secundário. O seu conteúdo curricular exige alterações constantes devido às exigências da sociedade e das leis educativas em Espanha. Este artigo apresenta uma investigação empírica qualitativa, cuja metodologia se baseia na Teoria Fundamentada. Embora o objetivo da investigação seja mais amplo, por razões de espaço, apresentamos aqui a parte que corresponde à análise do contexto organizacional e curricular do ponto de vista dos professores. Os entrevistadores recolheram dados através da observação, diário de campo e gravação de áudio dos grupos focais, com a participação de 68 professores de 17 escolas secundárias da província de Valência, atingindo a saturação teórica na oitava escola. O trabalho de campo foi realizado entre outubro de 2019 e fevereiro de 2020. O software Atlas.ti (v.8) foi utilizado para processamento de dados, permitindo a codificação aberta, axial, coocorrências e seletiva. As conclusões do estudo são: (1) a diferença em infraestruturas, dimensão e rácio repercute-se na qualidade da educação, (2) a coordenação institucional é necessária para adequar a transição dos estudantes entre diferentes os níveis de ensino, (3) a organização escolar juntamente com um currículo fragmentado em disciplinas nucleares, específicas e de livre escolha dificultam a aquisição de competências, e (4) a escolha das disciplinas STEM depende do sexo dos estudantes e do seu meio familiar.A disciplina de Tecnologia é uma disciplina transversal de conhecimentos e competências no currículo do Ensino Secundário. O seu conteúdo curricular exige alterações constantes devido às exigências da sociedade e das leis educativas em Espanha. Este artigo apresenta uma investigação empírica qualitativa, cuja metodologia se baseia na Teoria Fundamentada. Embora o objetivo da investigação seja mais amplo, por razões de espaço, apresentamos aqui a parte que corresponde à análise do contexto organizacional e curricular do ponto de vista dos professores. Os entrevistadores recolheram dados através da observação, diário de campo e gravação de áudio dos grupos focais, com a participação de 68 professores de 17 escolas secundárias da província de Valência, atingindo a saturação teórica na oitava escola. O trabalho de campo foi realizado entre outubro de 2019 e fevereiro de 2020. O software Atlas.ti (v.8) foi utilizado para processamento de dados, permitindo a codificação aberta, axial, coocorrências e seletiva. As conclusões do estudo são: (1) a diferença em infraestruturas, dimensão e rácio repercute-se na qualidade da educação, (2) a coordenação institucional é necessária para adequar a transição dos estudantes entre diferentes os níveis de ensino, (3) a organização escolar juntamente com um currículo fragmentado em disciplinas nucleares, específicas e de livre escolha dificultam a aquisição de competências, e (4) a escolha das disciplinas STEM depende do sexo dos estudantes e do seu meio familiar.在中等教育的课程设置中，科技课程是汇集多种知识和技能的交叉课程。由于西班牙教育法及社会环境的要求，课程内容需要不断地变化。因此该研究以扎根理论为方法依据，进行了定性观察研究。该研究的目标较广泛，但是出于篇幅限制，这里主要呈现了以教师视角出发对课程组织分析的部分。通过观察、田野调查、对焦点小组录音的方式收集数据。最后共有来自瓦伦西亚省17所中学的68名教师参与，在调查进行到第八所学校时，研究数据达到理论饱和。田野调查时间为2019年10月到2020年2月。在数据处理方面，研究使用可以进行开放、轴向、共现、选择编码的Atlas.ti（v.8）软件。研究最终得到的结论为：（1）基础设施规模及比例的差异影响到教学质量；（2）教学机构良好的协调能力可以促进学生在不同学习级别间的顺利转换；（3）断片式的主干课程、特定课程和自选课程的设置和组织阻碍了学生的能力获取；（4）学生的性别和家庭环境决定了学生对STEM（科学、技术、工程和数学）课程的选择