Search

This article presents an investigation into a historical invention consisting of a stationary steam engine designed by Henry Muncaster: a two-cylinder entablature steam engine with parallel motion crosshead. The present interdisciplinary research, based on the theoretical and methodological concepts of engineering drawing and computer-aided design, has allowed us to understand the operation of this invention from the 3D CAD model of the invention obtained thanks to the original drawings published in the magazine Model Engineer in 1957 and reproduced in 2017, since there is no descriptive information related to the invention. However, there have been drawbacks in the geometric modeling process since the dimensions of some components did not exist and in other cases they were erroneous. For this reason, dimensional, geometric and movement constraints (degrees of freedom) had to be applied so that said 3D CAD model would be coherent and functional, and an interference analysis also had to be performed. Finally, the existing symmetry in the arrangement of the cylinders and the crosshead has been discovered, it being essential to guarantee that the forces and movements are uniform on both sides of the steam engine, and allowing the work to be carried out in a more balanced manner by reducing vibrations and improving the overall efficiency of the invention. [ABSTRACT FROM AUTHOR]

Engineering Drawing (ED) is one of the fundamental courses for various engineering disciplines. However, first-year engineering undergraduates often face difficulties in learning and solving ED problems that require visualisation of 3D objects. Conventional and modern teaching methods do assist the teaching-learning of a subject but do not guarantee the elimination of the learning difficulties, specifically related to visualising spatial relationships. Mental rotation (MR) skills play a major role in learning such concepts, and students should be trained for the execution of MR processes. This paper presents a 3D visualisation tool-based training programme where students practice MR processes. The training guides students through hands-on tasks, coupled with the cognitive steps of MR. We investigate the effect of the training on improving 253 engineering undergraduates' ED problem-solving performance by administering a pipeline of four research studies. Results show that the training successfully helps students in enhancing their ED problem-solving performance. [ABSTRACT FROM AUTHOR]

Interactive Web Environments and multimedia tools are very common in engineering studies. However, these resources are very limited when graphical resolution is needed during the learning process. A learning environment that combines video and self-assessment Computer-Aided Design (CAD) tools was developed to analyse this problem and to determine if the combined use of these two tools may be important in learning these subjects. A comparative study of 124 engineering students was carried out. They were randomly assigned into three groups: Group-A using only traditional tools, Group-B using traditional tools and CAD tools, and Group-C using traditional tools, CAD tools, and video training. The statistical analysis of the results showed that a greater number of students of Group-C passed the test and improved their scores. Therefore, the combined use of these two types of resources can be an important aid in the study of subjects requiring graphic tools for their learning. [ABSTRACT FROM AUTHOR]

Engineering drawings are commonly used across different industries such as oil and gas, mechanical engineering and others. Digitising these drawings is becoming increasingly important. This is mainly due to the legacy of drawings and documents that may provide rich source of information for industries. Analysing these drawings often requires applying a set of digital image processing methods to detect and classify symbols and other components. Despite the recent significant advances in image processing, and in particular in deep neural networks, automatic analysis and processing of these engineering drawings is still far from being complete. This paper presents a general framework for complex engineering drawing digitisation. A thorough and critical review of relevant literature, methods and algorithms in machine learning and machine vision is presented. Real-life industrial scenario on how to contextualise the digitised information from specific type of these drawings, namely piping and instrumentation diagrams, is discussed in details. A discussion of how new trends on machine vision such as deep learning could be applied to this domain is presented with conclusions and suggestions for future research directions. [ABSTRACT FROM AUTHOR]

In under graduate engineering education, engineering drawing is a basic course offered to 1st semester engineering students. With the advent of computers, the traditional engineering drawing practice in both industry and academia is being extensively replaced with computer aided engineering drawing. The present scenario in Indian engineering educational institutions has been studied and based on it an approach is proposed in the present paper, which involves the integration of software-based practice with client–server architecture. The proposed approach has been implemented to practice in our institute for few years. The use of this approach is required proper planning of the course content, delivery, practice and evaluation. The detailed discussion on the approach and its implications are examined through results. All the stakeholders are benefited by adopting this approach. The present paper focuses on the use of drafting software for the practice of engineering drawing-based courses in a secured client–server environment. This proposed approach guarantees multiple cascading advantages of improved understanding and enhanced spatial visualization among students. The proposed approach has been implemented for the students who admitted in the academic year 2014–15. The end exam results of these students have been compared with results of the batch admitted in academic year 2013–14. It was observed that the number of failures in the proposed approach were reduced up to 85% compared to conventional mode. Further, it facilitates to modernize the conduct of courses, provides data security, optimizes the utilization of computing facilities and most importantly it tests the students for the understanding of the topic and not for their artistic skills. Ultimately, it makes the engineering students industry-ready by enhancing their employability skills. [ABSTRACT FROM AUTHOR]

Separation of text and non-text is an essential processing step for any document analysis system. Therefore, it is important to have a clear understanding of the state-of-the-art of text/non-text separation in order to facilitate the development of efficient document processing systems. This paper first summarizes the technical challenges of performing text/non-text separation. It then categorizes offline document images into different classes according to the nature of the challenges one faces, in an attempt to provide insight into various techniques presented in the literature. The pros and cons of various techniques are explained wherever possible. Along with the evaluation protocols, benchmark databases, this paper also presents a performance comparison of different methods. Finally, this article highlights the future research challenges and directions in this domain. [ABSTRACT FROM AUTHOR]

Many current Web-based learning environments facilitate the theoretical teaching of a subject but this may not be sufficient for those disciplines that require a significant use of graphic mechanisms to resolve problems. This research study looks at the use of an environment that can help students learn engineering drawing with Web-based CAD tools, including a self-correction component. A comparative study of 121 students was carried out. The students were divided into two experimental groups using Web-based interactive CAD tools and into two control groups using traditional learning tools. A statistical analysis of all the samples was carried out in order to study student behavior during the research and the effectiveness of these self-study tools in the learning process. The results showed that a greater number of students in the experimental groups passed the test and improved their test scores. Therefore, the use Web-based graphic interactive tools to learn engineering drawing can be considered a significant improvement in the teaching of this kind of academic discipline. [ABSTRACT FROM AUTHOR]

Spatial ability is one of the most important skills that an engineer, an architect or an artist should master. The conceptualizing process of an idea is the hardest stage of any creative process. Such a skill has become so vital that many authors believe its measure is critical to establish the likely academic and/or professional success, i.e. a noticeably defined type of intelligence. This paper has a description of basic concepts associated to spatial skill, showing a standardized assessment method for mind rotations, and also a statistical analysis of results for a sample of first semester students of Industrial Engineering in Francisco José de Caldas University in Bogota. The final section offers an analysis about some factors that may affect their performance and outlines feasible strategies to enable and develop spatial skill of new curricula students. It is a part of 'Generation and validation of curricula for development of spatial skills of Engineering students through ICT implementation', a project developed since August 2012. [ABSTRACT FROM AUTHOR]

Abstract: This study focuses on the comparison of traditional engineering drawings with a CAD (computer aided design) visualization in terms of user performance and eye movements in an applied context. Twenty-five students of mechanical engineering completed search tasks for measures in two distinct depictions of a car engine component (engineering drawing vs. CAD model). Besides spatial dimensionality, the display types most notably differed in terms of information layout, access and interaction options. The CAD visualization yielded better performance, if users directly manipulated the object, but was inferior, if employed in a conventional static manner, i.e. inspecting only predefined views. An additional eye movement analysis revealed longer fixation durations and a stronger increase of task-relevant fixations over time when interacting with the CAD visualization. This suggests a more focused extraction and filtering of information. We conclude that the three-dimensional CAD visualization can be advantageous if its ability to manipulate is used. [Copyright &y& Elsevier]

The quality of engineering drawings affects the inter-departmental information interchange of engineering objects in the industry, directly. Indirectly, it plays an important role in the manufacturing of engineering products because a poor quality drawing can produce an incomplete and/or incorrect product. Quality of a manually drawn engineering drawing is inspected through well established standards, however, the inspection of a computerized engineering (CE) drawing for its quality needs further research. In this paper, we have proposed different quality metrics to check the quality of a CE drawing in terms of its completeness and correctness. The proposed metrics can facilitate the engineering industry by saving the time and cost of manual inspection through automating the process. [ABSTRACT FROM AUTHOR]

Abstract: View identification is the basic process for solid reconstruction from engineering drawings. A new method is presented to label various views from a section-involved drawing and identify geometric planes through the object at which the sections are to be located. In the approach, a graph representation is developed for describing multiple relationships among various views in the 2D drawing space, and a reasoning technique based on evidence theory is implemented to validate view relations that are used to fold views and sections in the 3D object space. This is the first automated approach which can handle multiple sections in diverse arrangements, especially accommodating the aligned section for the first time. Experimental results are given to show that the proposed solution makes a breakthrough in the field and builds a promising basis for further expansibility, although it is not a complete one. [Copyright &y& Elsevier]

Since its early days, geometrical reconstruction (GR) has been developed as a stand-alone process for reconstructing a 3D CAD model from a 2D engineering drawing. Addressed in this paper is an attempt to extend GR application to interface it with the rapid prototyping process (RP) in order to construct a prototype directly from an engineering drawing. A layer-based geometric reconstruction (LBGR) concept has been developed to couple the two applications. LBGR locally translates information on the 2D drawing into a stack of contours section-by-section in a top-down direction, in which the top and bottom contours of each section are identified before its intermediate contours are generated. It can be applied to parts that consist of regular surfaces whose edges are clearly presented on the orthographic views (e.g. plane surfaces, conical surfaces, ruled surfaces with cross-sectional contours parallel with the xy plane). This concept has been implemented in LabVIEW to demonstrate this direct interface. Inputs and outputs are orthographic view images of a drawing and the vector files of contours, respectively. The direct transformation of mechanical part drawings into physical prototypes is also presented in this paper. [ABSTRACT FROM AUTHOR]

Recognition of engineering drawing entities is one of the most difficult stages in engineering drawing interpretation and many attempts to recognize various types of ED entities have been made. In this paper, we review algorithms for the recognition of ED entities, especially dimensions and crosshatching areas. For the recognition of dimensions, we analyze how dimension texts can be separated from graphics and how arrowheads of dimension lines are recognized. We also analyze the recent systems of ED interpretation. Finally, future tasks are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Engineering drawings produced by computer-aided design and drafting (CADD) software are widely employed in the construction industry, as well as many other manufacturing sectors. It is very common for a drawing plan to undergo many revisions, thus, many different versions of the drawing are generated before the final product is achieved. Thus, a drawing management system needs to maintain the history of different versions of drawings, and version control becomes a key function for any drawing management system. In this paper, a knowledge-based version information extraction method is presented. The method analyzes the layout of the drawing frame and extracts the version information with the help of predefined key words. Then a comparison method between two versions of drawing is introduced. The comparison method highlights the differences between two versions of the drawings, so that engineers can locate and find the changes quickly. [Copyright &y& Elsevier]

The wide applications of CAD/CAM technologies have promoted the development and application of many advanced technologies, such as digital manufacturing, rapid prototyping, enterprise resources planning, computer integrated manufacturing, concurrent engineering, virtual reality, and mass customization. These advanced technologies all need to be supported by three-dimensional (3D) solid models of products. Most enterprises, however, still organize their production using 2D paper drawings, which makes difficulties for the application of these advanced technologies. It is needed to convert engineering paper drawings into 3D solid models for applications. Based on holo-extraction of information from paper drawings, this paper develops a systematic 3D reconstruction method, which simulates an experienced human designer''s thinking mode in transforming inaccurate outlines with inaccurate projection relationships in 2D drawings into 3D image, with the aid of Genetic Algorithms. [Copyright &y& Elsevier]

After analyzing the existing methods, based on holo-extraction method of information, this paper develops a recognition method of digital curves scanned from paper drawings for subsequent pattern recognition and 3D reconstruction. This method is first to construct the networks of single closed region (SCRs) of black pixels with all the information about both segments and their linking points, to classify all the digital contours represented by SCRs into three types: straight-line segments, circular arcs, and combined lines, and then to decompose the combined lines into least basic sub-lines or segments (straight-line segments or circular arcs) with least fitting errors using genetic algorithms with adaptive probabilities of crossover and mutation and to determine their relationships (intersecting or being tangential to each other). It is verified that the recognition method based on the networks of SCRs and the genetic algorithm is feasible and efficient. This method and its software prototype can be used as a base for further work on subsequent engineering drawing understanding and 3D reconstruction. [Copyright &y& Elsevier]

In computer graphics one is often concerned with representing three-dimensional objects on a two-dimensional display surface. The choice of such a representation depends on several factors, including the purpose for which the representation is intended, the visual effects that are desired, and the shape of the object. This paper describes how two-dimensional views can be obtained using planar geometric projections such as perspective and parallel projections. It discusses how these projections can be generated from a three-dimensional representation of an object in a manner suitable for computer graphics systems. In particular, it shows how these projections can be generated using the viewing transformations of the Core Graphics System. The factors that affect the choice of projection are also discussed, and some guidelines for making such a choice are given. [ABSTRACT FROM AUTHOR]

" Engineering Drawing autonomous learning platform " provides a completely independent, opening, interactive learning environment for the engineering drawing learners and enthusiasts. The platform focuses on " electronic classroom", is assisted with " electronic laboratory" and supported by " learning management system" . The platform integrates the functions of teaching, learning, practice, test, and judgment. It has many features, such as autonomy, assistant, reproducibility, opening, interactivity and so on. When the learners log in, the management system wilprovide study Yuidance accordinYto the reYistration information. Learners can learn repeatedly and autonomously, practice in the " electronic classroom", see tri(dimensional models in the " electronic laboratory" . These functions wiil help) the learners to understand, master and expand of their knowledge. After finishing learning, the learners can log in the " examination system " to test the learning effect and then the system wiil guide the learners for their further learning. The platform keeps to the " student-centered" teaching philosophy, follows up the " learn for fun", " learn for knowledge" and " learn for life" training modes. This paper focused on the construction of the engineering drawing platform, and explores the mode for training the high quality military talents. [ABSTRACT FROM AUTHOR]