Rapid Prototyping in VR - Towards Virtual Clay Modelling

Keywords

Virtual Reality, Virtual and Immersive Environments, Computer-Aided Design, Solid Modelling, Clay Modelling, Octree, Spatial Data Structures

Project Description

Virtual Environments (VEs) have finally matured from proof-of-concept studies performed at university laboratories into fully featured applications. They are now applied to engineering design, research and development, manufacturing, medicine, architecture, marketing, geophysical explorations, and a variety of other fields.
VEs have the potential to revolutionize traditional industrial product design by enabling the transition from conventional keyboard and mouse-based computer-aided design (CAD) to fully virtual product design. A car design, for example, traditionally originates from a clay model that forms the basis for a numerical CAD description in Bezier, B-Spline, or NURBS format after digitization.
Furthermore, physical conceptual models, so called mock-ups, still play a key role in the otherwise CAD-centered development cycles. Our clay modelling project aims at closing this technology gap by merging classical design concepts with state-of-the-art visualization and interaction device technology, while emphasizing the creation of an intuitive and natural work environment.

The virtual clay modelling project explores the use of virtual environments (VEs) for the simulation of two-handed clay modelling and sculpting tasks.
Traditional clay modeliling concepts are implemented and enhanced with new digital design tools leveraging from virtual reality (VR) and new input device technology. In particular, the creation of an intuitive and natural work environment for comfortable and unconstrained modeling is emphasized.

VR projection devices, such as the Immersive WorkBench, shutter glasses, and pinch gloves, equipped with six-degree-of-freedom (6DOF) trackers, are used to apply various virtual cutting tools to a volumetric data structure (octree). The employment of an octree as underlying data structure for volume representation and manipulation in immersive environments allows real-time modeling of solids utilizing a suite of either geometrically or mathematically defined cutting and modeling tools.

A virtual clay model is encoded as an octree, preserving its volumetric and physical properties and design history. Incremental undo/redo functionality for rapid transitions between different modeling states increases the efficiency and flexibility, while advanced features of the primitive and wire cutting tools, such as the removal of single layers from a clay model, enhance the modeling procedure to a level of precision hardly achievable at this level of detail in real clay modeling.
Models can be passed to a raytracer or exported as either triangular or tetrahedral meshes. The resulting work environment can be utilized beyond the targeted application of virtual clay modeling, for example for the visualization and analysis of medical data.

The project was supported by the Visualization Thrust at the Center for Image Processing and Integrated Computing (CIPIC) at the University of California, Davis, U.S.A, and the AG Graphische Datenverarbeitung und Computergeometrie at the University of Kaiserslautern, Germany.

Publications

E. Moritz: Towards Rapid Prototyping With Immersive Clay Modelling: Exploring Volume Modelling in a Virtual Reality Environment, Project Thesis, University of Kaiserslautern, 2000

E. Moritz, F. Kuester, B. Hamann, K. I. Joy, H. Hagen: Towards Immersive Clay Modelling: Interactive Modelling with Octrees, in Stereoscopic Displays and Virtual Reality Systems VII, John O. Merrit, Stephen A. Benton, Andrew J. Woods, Mark T. Bolas (eds.), Proceedings of SPIE Vol. 3957, 2000, pp. 414-422

Contact Information

SnailMail

Elke Moritz

University of California, Irvine

Department of Electrical & Computer Engineering

649 Engineering Tower

Irvine, CA 92697-2625

USA

Phone/Fax

+1-(949)-824-3937 (work)

E-Mail

emoritz@uci.edu