1. Mixed Reality Benefits For Design Perception Phillip S. Dunston, Ph.D. and Xiangyu Wang Construction Engineering and Management School of Civil Engineering Purdue University, West Lafayette, IN Co-Authors: Mark Billinghurst, Ph. D. (Human Interface Technology Laboratory of New Zealand) and Ben Hampson (McKinstry Co., Seattle) 19 th ISARC Gaithersburg, MD September 2002

2. Outline Introduction AR CAD system Issues in Spatial Cognition Experimental Methodology Results Discussion Conclusion and Future Directions

3. Introduction Mixed Reality Mixed Reality (MR): an environment where real world and virtual world objects are presented together on a single display (Milgram & Kishino 1994; Milgram and Colquhoun 1999).

4. Introduction Industrial AR Applications (Azuma et al. 2001 by courtesy of Siemens Corporate Research) AR Viewing of Underground Utilities (Roberts et al. 2002)

5. Introduction Planning Phase Design Phase Construction Phase Maintenance Phase Conceptual Design Construction Documents (Plans and Specs) As-built Plans We are here right now Information Interfaces Involved in the Project Life Cycle

6. Introduction Mixed Reality Augmented Reality AR CAD System Focus on mechanical detailing

7. AR CAD System Hardware The AR CAD system consists of the following components Modeling computer: Running AutoCAD or other modeling software. AR computer: Running the Augmented Reality viewing software. Video Camera: Logitech QuickCam Pro 3000. Components of AR CAD Prototype

8. AR CAD System Tracking Technology The Process of Video-Based Marker Detection and Overlay of Virtual Objects

9. AR CAD System Tracking Technology User View of Virtual Objects in Augmented Reality (AR) Scene

10. AR CAD System Tracking Technology User View of Virtual Objects in Augmented Reality (AR) Scene

11. Issues in Spatial Cognition Spatial cognition is the internalized reflection and reconstruction of space in thought (Hart and Moore, 1973). Why explore spatial cognition? To understand the structure (coding) of the mental models and the process of utilizing those mental models (decoding). To most efficiently present and effect spatial information via the human-computer interface.

12. Issues in Spatial Cognition Main Process Main Processes of Human Spatial Cognition Extracting process: obtaining spatial information from physical space. Storage or encoding process: building a memory representation from visual perception. Decoding process: retrieving information from memory for decision making.

13. Issues in Spatial Cognition Cognition Cost Cognition Cost Indication of the effort required by different mental transformations associated with changes and factors involved in switching viewing perspectives.

14. Issues in Spatial Cognition Viewpoint Comparison Viewpoint Comparison between AR and AutoCAD

15. Experimental Methodology Objective Primary Objective: To determine whether standard AutoCAD or AR CAD (AutoCAD + AR view) is more effective in the task of conflict detection with respect to the cognition cost associated with scene/perspective changes.

16. Experimental Methodology Interference Detection Wire Frame Representation of Object Interferences

17. Results Discussion = Estimated time value

18. Results Discussion CombinationMean Value(sec)Median Value(sec) AutoCAD®+P1196.75134.50 AR CAD+P150.7549.50 AutoCAD®+P274.7565.50 AR CAD+P228.5027.00 Mean and Median Value of Each Combination

19. Conclusion and Future Directions Conclusion AR CAD can be a worthwhile viewer assistant for identifying interferences without increasing a detailer’s overall time due to the cognition cost associated with perspective switching. Future Directions Continued exploration of human interface issues, e.g., spatial cognition Computer Supported Cooperative Work (CSCW)

20. Conclusion and Future Directions Collaborative work Concept by Andrei State at University of North Carolina at Chapel Hill

21. Questions? Dr. Phillip S. Dunston 765-494-0640 dunston@purdue.edu Mr. Xiangyu Wang wang0@purdue.edu