Mental rotation, a common measure of spatial ability, has traditionally been assessed through paper-based instruments like the Mental Rotation Test (MRT) or the Purdue Spatial Visualization Test: Rotations (PSVT:R). The fact that these instruments present 3D shapes in a 2D format devoid of natural cues like shading and perspective likely limits their ability to accurately assess the fundamental skill of mentally rotating 3D shapes. In this paper, we describe the Virtual Reality Mental Rotation Assessment (VRMRA), a virtual reality-based mental rotation assessment derived from the Revised PSVT:R and MRT. The VRMRA reimagines traditional mental rotation assessments in a room-scale virtual environment and uses hand-tracking and elements of gamification in attempts to create an intuitive, engaging experience for test-takers. To validate the instrument, we compared response patterns in the VRMRA with patterns observed on the MRT and Revised PSVT:R. For the PSVT:R-type questions, items requiring a rotation around two axes were significantly harder than items requiring rotations around a single axis in the VRMRA, which is not the case in the Revised PSVT:R. For the MRT-type questions in the VRMRA, a moderate negative correlation was found between the degree of rotation in the X direction and item difficulty. While the problem of occlusion was reduced, features of the shapes and distractors accounted for 50.6% of the variance in item difficulty. Results suggest that the VRMRA is likely a more accurate tool to assess mental rotation ability in comparison to traditional instruments which present the stimuli through 2D media. Our findings also point to potential problems with the fundamental designs of the Revised PSVT:R and MRT question formats.

Virtual product presentations that rely on static images and text are often insufficient to communicate all the information that is necessary to accurately evaluate a product. Technologies such as Virtual Reality (VR) or Augmented Reality (AR) have enabled more sophisticated representation methods, but certain product characteristics are difficult to assess and may result in perceptual differences when a product is evaluated in different visual media. In this article, we report two case studies in which a group of participants evaluated three designs of two product typologies (i.e., a desktop telephone and a coffee maker) as presented in three different visual media (i.e., photorealistic renderings, AR, and VR for the first case study; and photographs, a non-immersive virtual environment, and AR for the second case study) using eight semantic scales. An inferential statistical method using Aligned Rank Transform (ART) proceedings was applied to determine perceptual differences between groups. Our results show that in both cases product attributes in Jordan's physio-pleasure category are the most affected by the presentation media. The socio-pleasure category was also affected for the case of the coffee makers. The level of immersion afforded by the medium significantly affects product evaluation.

Digital product data quality and reusability has been proven a critical aspect of the Model-Based Enterprise to enable the efficient design and redesign of products. The extent to which a history-based parametric CAD model can be edited or reused depends on the geometric complexity of the part and the procedure employed to build it. As a prerequisite for defining metrics that can quantify the quality of the modeling process, it is necessary to have CAD datasets that are sorted and ranked according to the complexity of the modeling process. In this paper, we examine the concept of perceived CAD modeling complexity, defined as the degree to which a parametric CAD model is perceived as difficult to create, use, and/or modify by expert CAD designers. We present a novel method to integrate pair-wise comparisons of CAD modeling complexity made by experts into a single metric that can be used as ground truth. Next, we discuss a comprehensive study of quantitative metrics which are derived primarily from the geometric characteristics of the models and the graph structure that represents the parent/child relationships between features. Our results show that the perceived CAD modeling complexity metric derived from experts’ assessment correlates particularly strongly with graph-based metrics. The Spearman coefficients for five of these metrics suggest that they can be effectively used to study the parameters that influence the reusability of models and as a basis to implement effective personalized learning strategies in online CAD training scenarios.

The use of collaborative applications in which several individuals interact to solve a problem is an important strategy both in educational settings as well as professional environments. Virtual Reality (VR) technology, in particular, has acquired a predominant role in many industries. However, as the level of immersion and realism of the VR experience increases, so does the demand for computational resources, as rendering processes become increasingly intensive and can negatively affect other communication processes that are critical in collaborative environments. In this paper, we present a software framework based on multi-agent systems that enables the separation of rendering processes from internal data management tasks and communication processes between users, which are prevalent in collaborative virtual reality applications. The results of our validation studies show that, compared to other techniques based on protocol or network enhancements, the proposed architecture can significantly improve collaborative processes in general, and virtual reality-based applications in particular.

In this full paper, we describe a design activity method for developing research questions and present a study on student's perception to validate it. We examine, compare and discuss results from three different graduate student cohorts (first, second, and third semester Master's degree students) who used the worksheet method at different stages of their graduate careers. The method is designed to help students identify topics, think critically about the underlying questions to explore a topic, identify a problem to be addressed by the research, and identify data sources to facilitate the research effort. The four stages are introduced as an incremental scaffolding process. Preliminary results showed graduate students found the worksheets effective in helping to develop research questions. This work contributes to the development of research practices and pedagogy supported by sound research questions.

In this article, visual perception principles were used to build an artificial perception model aimed at developing an algorithm for detecting junctions in line drawings of polyhedral objects that are vectorized from hand-drawn sketches. The detection is performed in two dimensions (2D), before any 3D model is available and minimal information about the shape depicted by the sketch is used. The goal of this approach is to not only detect junctions in careful sketches created by skilled engineers and designers but also detect junctions when skilled people draw casually to quickly convey rough ideas. Current approaches for extracting junctions from digital images are mostly incomplete, as they simply merge endpoints that are near each other, thus ignoring the fact that different vertices may be represented by different (but close) junctions and that the endpoints of lines that depict edges that share a common vertex may not necessarily be close to each other, particularly in quickly sketched drawings. We describe and validate a new algorithm that uses these perceptual findings to merge tips of line segments into 2D junctions that are assumed to depict 3D vertices.

This paper builds on the authors' previous work with Augmented Reality (AR) technology as a tool to enhance traditional visualizations and facilitate the understanding of complex information. In this paper, we expand our previous work with AR technology by focusing on the process of creating custom content. Based on users' feedback, we describe and compare various strategies to create 3D models from real objects that can be subsequently integrated into augmented reality scenes. Specifically, we evaluate current 3D scanning technologies that are affordable and suitable for educational applications. We present a comparative analysis of low-cost 3D scanning technologies, its use, integration with AR, and implementation as educational tools. Factors considered in our study include portability, model size, resolution, and postproduction requirements.

Information and Communication Technologies (ICTs) have played a major role in shaping our society, affecting nearly all aspects of our daily lives. In educational contexts, the ongoing technological revolution we are experiencing naturally calls for a transformation of traditional teaching and learning processes. The integration and efficient use of emergent technologies have become fundamental challenges in the educational domain. In this paper, we evaluate the use of Augmented Reality (AR) technology in a classroom with middle school special-needs students. Our primary goal is to quantitatively assess whether AR helps special-needs students to improve their results, performance, motivation, and other aspects of the learning process. Information was collected via pre and post questionnaires distributed to participants before and after an intervention. Our results serve as basis for improving future educational AR-related projects and materials.

This paper builds on the authors' previous work with Augmented Reality (AR) technology, where interactive three-dimensional (3D) content was developed and combined with traditional printed materials to enhance the visualization and understanding of technical information. In this study, we describe a method to rapidly create custom marker-based AR content using 3D data from real objects and an authoring tool developed in-house. We present a two step process, where 3D geometry is generated automatically by capturing and processing a series of photographs of a real object and subsequently converted to an AR element that can be linked to a unique marker and used with a marker-based AR system. This system provides an opportunity for instructors to quickly and effortlessly create their own AR content to support their innovative teaching practices.

The development of knowledge-based engineering systems and their integration with CAD environments require the use of efficient user interfaces, communication tools, and practical mechanisms to elicit knowledge in order to avoid information-acquisition bottlenecks. Therefore, it is critical to design systems that do not overload users with information and facilitate the representation of knowledge in a simple and friendly manner. The concept of “extended annotation” as a tool to communicate knowledge is a mechanism based on using 3D annotations directly within CAD models, so that stakeholders that participate in the design process can associate textual information to the various aspects of the model, facilitating design intent and design rationale communication. In this paper, we incorporate communication functionalities to the extended annotation concept by presenting an interactive mechanism based on video conferencing that enables users to quickly communicate with the model annotators in situations where the contents of the annotation need to be extended or clarified. This approach eliminates the need for separate communication tools and provides a collaborative space that is built directly into the CAD interface. The system architecture and the foundations for its implementation are described in the final section of the paper. An initial evaluation of a software prototype has shown positive reactions and acceptance among users.

In this paper, we present a computer assisted creativity tool based on natural interfaces that allows the creation of distributed collaborative workspaces by merging the real and digital worlds in a tabletop setting. These workspaces are used to promote the exchange and sharing of graphical information by simulating a physical workbench where designers traditionally work with paper sketches, images, and handwritten notes. Our tool allows users to manage and organize images and textual notes in a natural manner. The application is multiplatform with support for the TUIO protocol and can be run on one or multiple tabletops that can interact with one another. Each group of designers can use a tabletop system, which becomes an interactive window to a virtual common desktop. We present a case study where our team successfully implemented and tested the system in an international collaborative design project.

This paper describes the results of a comparative pilot study of three different approaches to deliver three-dimensional content in an Engineering Design Graphics textbook using Augmented Reality: Desktop Augmented Reality, Mobile Augmented Reality, and an interactive 3D viewer. This work builds on a previous version of our augmented book, which only implements Desktop Augmented Reality. In this extended version, two new visualization mechanisms for mobiles devices were incorporated with the purpose of improving the students' visualization skills. A small group of users was selected to evaluate the usability of the technology and the effectiveness of the materials. In general, participants showed mixed reactions in terms of their preferred method to interact with the content. Nevertheless, we observed a general positive attitude, excitement, and a high level of user satisfaction, which suggests that augmented reality can be a valuable method for self-directed learning and self-assessment.

In this paper, we compare a classic collaborative workspace designed to develop creative skills of Industrial Design students with a digital approach using blended spaces and ubiquitous computing. We adapted a distributed digital collaborative workspace previously developed by our team to a new system that we call "The Ideas Machine." This system is capable of suggesting new ideas and research tips to students based on various methodologies of creativity and the initial input provided by the instructor. The system is designed for interactive tabletop systems, which promote collaboration by supporting face-to-face communication around a large work area. Since digital spaces facilitate the acquisition of a variety of data in real time, our system allows instructors to gather extensive and up-to-date information from students that could not be obtained otherwise in a traditional environment because of technical and time constraints. Leveraging this capability, we developed a mechanism that acts as an assistant to the instructor by automatically evaluating students according to certain parameters. Finally, to assess the capabilities of our system as a tool to support creativity, we conducted an experiment with Industrial Design students over the course of an academic year. Information used to evaluate efficiency includes student qualifications, number of information items provided and shared (sketches, images, etc.), and number and quality of new ideas generated.

This paper describes the development and integration of augmented reality content with traditional Engineering Design Graphics materials, and presents the results of a preliminary usability study conducted with Freshman Engineering students. The resources developed combine printed text and images with interactive three-dimensional content with the purpose of enhancing the understanding of technical graphics concepts and improving the students' visualization skills. In general, students had a very positive reaction when first presented with the materials and showed an optimistic attitude while interacting with the content. Additionally, augmented reality materials promote the development of self-directed learning skills and self-assessment.

Dimensioning plays an important role in the product development process. It is usually learned through sketching exercises where students add the corresponding dimensions to different parts of an engineering drawing. Nevertheless, being able to self-learn proper dimensioning methods is challenging, as a geometric figure requires a specific number of dimensions to be correctly defined. This paper presents an educational software application for multi-touch tablet devices to support dimensioning activities. Our application uses a multi-touch interface where students can create 2D parametric drawings with dimensions using freehand sketches and receive feedback from the system about the quality of their dimensioning exercises. When a student finishes a sketch, the system reports back the correct and incorrect dimensions. Multi-touch gestures are also used for basic sketch manipulation (panning, zooming, and rotating), similar to the standard functionality found in modern smart phones and tablets. Preliminary experiences show that multi-touch interfaces provide an effective way to capture students' attention. Students found the system very natural, and the time required to learn how to use the application is short. They enjoyed the simplicity of the interface and valued the powerful control of the geometry.

Collaborative learning is an effective educational method that plays an essential role in theories such as Constructivism and Knowledge Building. Studies have shown that collaborative work in small groups significantly improves learning when supported by concept maps. Although useful in collaborative environments, most applications available for the development of concept maps are designed for personal or small tablet computers, which can limit student communication in a team. In addition, the use of these applications usually requires learning or training periods, which can also interfere with the learning process. In this paper, we present a software tool for generating concept maps and constructing learning spaces under both local and distributed collaboration scenarios. Our system uses a natural interface with multi-touch and multi-user capabilities. It was specifically designed for tabletop systems, which provide a large horizontal interactive surface suitable for collaboration and face-to-face communication. The tool is also available in other platforms, which makes it useful in a variety of classroom orchestration settings. Finally we present the results of a preliminary usability study of our tool in a real educational environment.

In this paper, we present a functional prototype of an interactive multi-touch book with drawing capabilities, intended to enhance the understanding of engineering graphics concepts and improve visualization skills. Our multi-touch book combines textual elements with rich media content and interactive exercises to allow students to practice technical sketching in an environment that simulates traditional paper-based drawings and tools. Additionally, finished drawings can be submitted to the instructor via email directly from the digital book, which facilitates management tasks. A comparative study of traditional and digital sketching using our prototype was conducted with a small group of participants to evaluate the effectiveness of the tool. Preliminary results show positive reactions and acceptance.