Nathan W. Hartman

Virtual reality-based spatial skills assessment and its role in computer graphics education

One element of using contemporary computer graphics tools is the creation of accurate 3D geometry for a variety of purposes. As part of developing effective instructional experiences for students engaged in such activities, computer graphics educators must take into account a persons spatial abilities and skills. Literature has shown these abilities are widely considered to be a significant predictor of the probability of a persons success in computer graphics-related professions. Typical spatial skills assessments examine such abilities as mental rotations, spatial visualization, and spatial perception all of which are involved in the creation of 3D computer graphics. However, most of these assessment instruments are paper-based, and the nature of the human ability being measured is such that the paper-and-pencil format currently used has no mapping to the target construct domain - namely 3D computer graphics in the real world.This lack of authenticity puts into serious question not only the perceived validity (face validity) of the test, but also the purposes for which test scores from the assessment instruments are put to use (construct validity). One such instrument is The Mental Cutting Test (MCT) which is commonly used to measure spatial visualization skills relative to a cutting plane passing through an object, which are critical in the use of many contemporary computer graphics tools. In an effort to minimize validity issues, the cognitive psychology and computer graphics communities have begun developing virtual reality-based versions of mental rotations instruments to examine various constructs. But a mental rotations assessment does not provide a complete coverage of a persons spatial abilities. This paper outlines the relationship to spatial abilities and computer graphics education and a methodology for pilot testing a working prototype of a virtual reality-based version of a spatial abilities assessment instrument which uses the MCT as a model.

Spatial abilities and virtual technologies: examining the computer graphics learning environment

Research in the area of spatial visualization enjoys a long tradition in the discipline of cognitive psychology. However, the computer graphics profession, particularly the educational component, takes into account a persons spatial abilities as a means for designing effective instructional experiences and assessments. It builds on a learners visual or haptic abilities. This paper outlines a brief history of visualization assessments instruments and strategies and their use within computer graphics-related learning environments. The use of virtual reality technologies to enable the learning process is discussed, as well as an introduction to visual science as a discipline.

Identified research directions for using manufacturing knowledge earlier in the product life cycle

Design for manufacturing (DFM), especially the use of manufacturing knowledge to support design decisions, has received attention in the academic domain. However, industry practice has not been studied enough to provide solutions that are mature for industry. The current state of the art for DFM is often rule-based functionality within computer-aided design (CAD) systems that enforce specific design requirements. That rule-based functionality may or may not dynamically affect geometry definition. And, if rule-based functionality exists in the CAD system, it is typically a customisation on a case-by-case basis. Manufacturing knowledge is a phrase with vast meanings, which may include knowledge on the effects of material properties decisions, machine and process capabilities or understanding the unintended consequences of design decisions on manufacturing. One of the DFM questions to answer is: How can manufacturing knowledge, depending on its definition, be used earlier in the product life cycle to enable a more collaborative development environment? This paper will discuss the results of a workshop on manufacturing knowledge that highlights several research questions needing more study. This paper proposes recommendations for investigating the relationship of manufacturing knowledge with shape, behaviour and context characteristics of a product to produce a better understanding of what knowledge is most important. In addition, the proposal includes recommendations for investigating the system-level barriers to reusing manufacturing knowledge and how model-based manufacturing may ease the burden of knowledge sharing. Lastly, the proposal addresses the direction of future research for holistic solutions of using manufacturing knowledge earlier in the product life cycle.

Product lifecycle management in design and engineering education: International perspectives

Technological advances in the last decade have influenced changes in the design and engineering industries on a global scale. Lean and collaborative product development are approaches increasingly adopted by the industry and seen as the core of product lifecycle management. These trends have created the need for new skilled professionals, and universities should adapt their curricula in response. There is an increased need for academia to work with industry in order to meet these challenges. This article reports on the Parametric Technology Corporation Academic Research Symposium held in April 2011. The topics were centred around understanding the essence of product lifecycle management and its impact on design and engineering education. Furthermore, examples of implementing product lifecycle management and collaborative practices in higher education were presented from the United States and France. This article concludes with a discussion of the recommendations made at the symposium for the future development and support of key skills across university curricula.

Promoting Model-Based Definition to Establish a Complete Product Definition

The manufacturing industry is evolving and starting to use 3D models as the central knowledge artifact for product data and product definition, or what is known as Model-based Definition (MBD). The Model-based Enterprise (MBE) uses MBD as a way to transition away from using traditional paper-based drawings and documentation. As MBD grows in popularity, it is imperative to understand what information is needed in the transition from drawings to models so that models represent all the relevant information needed for processes to continue efficiently. Finding this information can help define what data is common amongst different models in different stages of the lifecycle, which could help establish a Common Information Model. The Common Information Model is a source that contains common information from domain specific elements amongst different aspects of the lifecycle. To help establish this Common Information Model, information about how models are used in industry within different workflows needs to be understood. To retrieve this information, a survey mechanism was administered to industry professionals from various sectors. Based on the results of the survey a Common Information Model could not be established. However, the results gave great insight that will help in further investigation of the Common Information Model.

Metrics for the cost of proprietary information exchange languages in intelligent systems

The increasing number of intelligent software components is accompanied by an increasing number of proprietary information exchange languages between components. One of the challenges for the smart technology worker is to achieve intelligent system component interoperability, at the lowest cost possible, without sacrificing the freedom to choose from the entire spectrum of current and future software product offerings. This is best achieved when correct, complete, and unambiguous information exchange standards are implemented in vendor products worldwide. If this is the common sense solution to information incompatibility costs and risks, why is standards-based interoperability so rarely seen? One reason is that a required investment in standards must precede the savings gotten from true interoperability. Corporate management is commonly reluctant to commit to this investment, partly because there appears to be no published set of interoperability cost metrics which technology workers can employ to make an evidence-based business case. This research seeks to remedy this situation by defining realistic, comprehensive, and sector-independent cost-risk metrics.

Examining the Use of Model-Based Work Instructions in the Aviation Maintenance Environment

A fundamental tenet of product lifecycle management (PLM) environments is the use of high-fidelity, 3D product models. The capability to create models with high degrees of fidelity to the physical world has driven companies to extract as much benefit and use from these digital assets as possible throughout the design, production, and support stages of the lifecycle. This is particularly apparent in the aviation industry where aircraft lifecycles routinely reach 80 years or longer. As the aviation industry migrates to the use of 3D model-based communications mechanisms in lieu of 2D drawings, multiple factors will impact the use of digital model-based work instructions, including the device, the form of the product model data, and levels of detail in geometry and interactivity. This paper will present a series of short studies conducted over the last three years using novice university students and expert university staff aircraft mechanics to evaluate the use of model-based work instructions in a general aviation maintenance environment. The results indicate that varying levels of detail and levels of interactivity have an effect on number of errors, time on task, and mental workload.

A Framework for Evaluating Collaborative Product Representations in Product Lifecycle Workflows

Product definition technology has evolved in such a way as to encourage the proliferation of data formats used within the product lifecycle for various use cases. One such product development framework being proposed in industry today is the model-based enterprise (MBE), which is operationally driven by the model-based definition (MBD) of products. This paper describes current models of the product development process and the nature of collaborative data. This paper will also suggest a framework for evaluating various collaborative product representations. The nature of the data formats chosen for use in specific workflows have a substantial effect on the ability of users to consume data and the ability for an organization to capture and archive its critical information.

Towards an extended model-based definition for the digital twin

ABSTRACTThe concept of the digital twin calls for virtual replicas of real world products. Achieving this requires a sophisticated network of models that have a level of interconnectivity. The authors attempted to improve model interconnectivity by enhancing the computer-aided design model with spatially related non-geometric data. A tool was created to store, visualize, and search for spatial data within the computer-aided design tool. This enables both model authors, and consumers to utilize information inside the CAD tool which traditionally would have existed in separate software.

Towards Identifying the Elements of a Minimum Information Model for Use in a Model-Based Definition

The Model-Based Enterprise (MBE) paradigm is being adopted by manufacturing companies in a variety of industries. Companies benefit from enhanced visualization, documentation, and communication capabilities when 3D annotated product definitions, or Model-Based Definitions (MBD) replace two-dimensional drawings throughout an enterprise. It is critical that product information, much of which is defined implicitly in drawings, is not lost in this transition. This presents a challenge to authors and translators of 3D models used through the product lifecycle. They must understand the semantics of the product information typically presented by a drawing then explicitly include this information, in a computer-interpretable form, in the MBD.The research study described in this paper seeks to discover what is the minimum set of required information to carry out all the tasks in a given workflow of a model-based enterprise. A survey was conducted across various industry sectors to identify the foundational elements of this Minimum Information Model (MIM) in selected workflows. This study identified the information used within the specific workflows, the capabilities of 3D CAD models to carry this information, and the implications for doing so.Copyright