Design, implementation, and testing of advanced virtual coordinate-measuring machines

Copyright @ 2011 IEEE. This article has been made available through the Brunel Open Access Publishing Fund.Advanced virtual coordinate-measuring machines (CMMs) (AVCMMs) have recently been developed at Brunel University, which provide vivid graphical representation and powerful simulation of CMM operations, together with Monte-Carlo-based uncertainty evaluation. In an integrated virtual environment, the user can plan an inspection strategy for a given task, carry out virtual measurements, and evaluate the uncertainty associated with the measurement results, all without the need of using a physical machine. The obtained estimate of uncertainty can serve as a rapid feedback for the user to optimize the inspection plan in the AVCMM before actual measurements or as an evaluation of the measurement results performed. This paper details the methodology, design, and implementation of the AVCMM system, including CMM modeling, probe contact and collision detection, error modeling and simulation, and uncertainty evaluation. This paper further reports experimental results for the testing of the AVCMM

The Effects of Task, Task Mapping, and Layout Space on User Performance in Information-Rich Virtual Environments

How should abstract information be displayed in Information-Rich Virtual Environments (IRVEs)? There are a variety of techniques available, and it is important to determine which techniques help foster a user’s understanding both within and between abstract and spatial information types. Our evaluation compared two such techniques: Object Space and Display Space. Users strongly prefer Display Space over Object Space, and those who use Display Space may perform better. Display Space was faster and more accurate than Object Space for tasks comparing abstract information. Object Space was more accurate for comparisons of spatial information. These results suggest that for abstract criteria, visibility is a more important requirement than perceptual coupling by depth and association cues. They also support the value of perceptual coupling for tasks with spatial criteria

Sketching space

In this paper, we present a sketch modelling system which we call Stilton. The program resembles a desktop VRML browser, allowing a user to navigate a three-dimensional model in a perspective projection, or panoramic photographs, which the program maps onto the scene as a `floor' and `walls'. We place an imaginary two-dimensional drawing plane in front of the user, and any geometric information that user sketches onto this plane may be reconstructed to form solid objects through an optimization process. We show how the system can be used to reconstruct geometry from panoramic images, or to add new objects to an existing model. While panoramic imaging can greatly assist with some aspects of site familiarization and qualitative assessment of a site, without the addition of some foreground geometry they offer only limited utility in a design context. Therefore, we suggest that the system may be of use in `just-in-time' CAD recovery of complex environments, such as shop floors, or construction sites, by recovering objects through sketched overlays, where other methods such as automatic line-retrieval may be impossible. The result of using the system in this manner is the `sketching of space' - sketching out a volume around the user - and once the geometry has been recovered, the designer is free to quickly sketch design ideas into the newly constructed context, or analyze the space around them. Although end-user trials have not, as yet, been undertaken we believe that this implementation may afford a user-interface that is both accessible and robust, and that the rapid growth of pen-computing devices will further stimulate activity in this area

Analysis domain model for shared virtual environments

The field of shared virtual environments, which also encompasses online games and social 3D environments, has a system landscape consisting of multiple solutions that share great functional overlap. However, there is little system interoperability between the different solutions. A shared virtual environment has an associated problem domain that is highly complex raising difficult challenges to the development process, starting with the architectural design of the underlying system. This paper has two main contributions. The first contribution is a broad domain analysis of shared virtual environments, which enables developers to have a better understanding of the whole rather than the part(s). The second contribution is a reference domain model for discussing and describing solutions - the Analysis Domain Model

The renaissance of the theatre of memory

Giulio Camillo (1480 - 1544) was as well-known in his era as Bill Gates is now. Just like Gates he cherished a vision of a universal Storage and Retrieval System, and just like Microsoft Windows, his ‘Theatre of the Memory’ was, despite constant revision, never completed. Camillo’s legendary Theatre of Memory remained only a fragment, its benefits only an option for the future. When it was finished, the user - so he predicted - would have access to the knowledge of the whole universe. On account of his promising invention, Camillo’s contemporaries called him ‘the divine’. For others, like Erasmus or the Parisian scholars, he was just a ‘quack’, but also this only shows that his reception was as strong as is the case with the computer gurus of our days. Still, Camillo was forgotten immediately after his death. No trace is left of his spectacular databank - except a short treatise which he dictated on his deathbed and which was formulated in the future tense: ‘L’Idea del Theatro’ (1550). ..

A software toolkit for web-based virtual environments based on a shared database

We propose a software toolkit for developing complex web-based user interfaces, incorporating such things as multi-user facilities, virtual environments (VEs), and interface agents. The toolkit is based on a novel software architecture that combines ideas from multi-agent platforms and user interface (UI) architectures. It provides a distributed shared database with publish-subscribe facilities. This enables UI components to observe the state and activities of any other components in the system easily. The system runs in a web-based environment. The toolkit is comprised of several programming and other specification languages, providing a complete suite of systems design languages. We illustrate the toolkit by means of a couple of examples

Design of an Anatomy Information System

Biology and medicine rely fundamentally on anatomy. Not only do you need anatomical knowledge to understand normal and abnormal function, anatomy also provides a framework for organizing other kinds of biomedical data. That’s why medical and other health sciences students take anatomy as one of their first courses. The Digital Anatomist Project undertaken by members of the University of Washington Structural Informatics Group aims to “put anatomy on a computer” in such a way that anatomical information becomes as fundamental to biomedical information management as the study of anatomy is to medical students. To do this we need to develop methods for representing anatomical information, accessing it, and reusing it in multiple applications ranging from education to clinical practice. This development process engenders many of the core research areas in biological structural informatics, which we have defined as a subfield of medical informatics dealing with information about the physical organization of the body. By its nature, structural information proves highly amenable to representation and visualization by computer graphics methods. In fact, computer graphics offers the first real breakthrough in anatomical knowledge representation since publication of the first scholarly anatomical treatise in 1546, in that it provides a means for capturing the 3D dynamic nature of the human body. In this article we explain the nature of anatomical information and discuss the design of a system to organize and access it. Example applications show the potential for reusing the same information in contexts ranging from education to clinical medicine, as well as the role of graphics in visualizing and interacting with anatomical representations

A telepresence environment for concurrent life-cycle design and construction

Construction projects normally involve transient 'virtual organisations', where a multidisciplinary project team works together on the design and construction of a facility. Many of these participants often work independently while taking decisions that inevitably affect others. The research described in the thesis involved examining the adoption of concurrent engineering (CE) principles by the construction industry as a way to reduce the problems posed by the fragmentation of the industry, and to enhance its competitiveness. An important aspect of concurrent engineering in construction is the need for effective communication of design information between all members of the project team and across all stages of the constructed facility's life-cycle. The thesis describes the development of a communications infrastructure for Concurrent Life-Cycle Design and Construction. [Continues.