Corba-Based Collaboration in a Virtual Assembly Design Environment

Abstract The use of virtual environments to plan and evaluate assembly processes has been gaining significant acceptance in the engineering community. The prohibitive costs of immersive virtual environments and the availability of the internet have brought to the forefront the need for methods for sharing the virtual environment during the assembly evaluation process. This will support true collaborative engineering. This paper presents the design and implementation of a CORBA-based distributed virtual assembly environment. The architecture is based on capturing key states and events in the virtual assembly process. This collaborative environment is based on the VADE system created at Washington State University. Test cases were conducted using this system and the results are presented in this paper.

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A Collision Contact Modeling Method for Rigid Bodies Represented as Triangle Meshes

Volume 4: 24th Computers and Information in Engineering Conference ◽

10.1115/detc2004-57725 ◽

2004 ◽

Author(s):

Qiang Wu ◽

Sankar Jayaram ◽

Uma Jayaram

Keyword(s):

Virtual Environments ◽

Rigid Bodies ◽

Modeling Method ◽

Dynamics Simulation ◽

Test Cases ◽

Triangle Mesh ◽

Design Environment ◽

Contact Modeling ◽

Triangle Meshes ◽

Assembly Design

In this paper, a collision contact modeling method for virtual reality environments is presented. Models in virtual environments are typically represented using triangle meshes. Most traditional collision contact simulations require the surface information of rigid bodies. This makes traditional collision contact simulations inapplicable for most virtual environments. This paper presents methods to model the behavior of colliding objects in virtual environments using triangle mesh representations of the objects. RAPID™ is used to obtain the approximate collision contact information between individual triangle meshes. Impulse calculations are combined with the collision detection to simulate post-collision behavior of objects. A three-point method is introduced to calculate the final resting place of objects or calculate unstable equilibrium and further dynamics of objects. These methods have been integrated with the Virtual Assembly Design Environment (VADE) to enhance VADE’s existing dynamics simulation capabilities. A series of test cases are presented and analyzed to validate these new methods.

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Virtual Assembly Design Environment

ASME 1995 15th International Computers in Engineering Conference and the ASME 1995 9th Annual Engineering Database Symposium ◽

10.1115/cie1995-0816 ◽

1995 ◽

Author(s):

Hugh I. Connacher ◽

Sankar Jayaram ◽

Kevin Lyons

Keyword(s):

Virtual Reality ◽

Research Effort ◽

New Technology ◽

Natural Extension ◽

Virtual Assembly ◽

Software Systems ◽

Design Environment ◽

Cad System ◽

Assembly Design ◽

Design And Manufacturing

Abstract Virtual reality is a technology which is often regarded as a natural extension to 3D computer graphics with advanced input and output devices. This technology has only recently matured enough to warrant serious engineering applications. The integration of this new technology with software systems for engineering, design and manufacturing will provide a new boost to the field of computer-aided engineering. One aspect of design and manufacturing which may be significantly affected by virtual reality is design for assembly. This paper presents the ideas behind a current research effort aimed at creating a virtual assembly design environment and integrating that environment with a commercial, parametric CAD system.

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Quality Management of Student-Student Evaluations

Journal of Educational Computing Research ◽

10.2190/0gcn-38hr-q0au-9gq4 ◽

1997 ◽

Vol 17 (3) ◽

pp. 199-215 ◽

Cited By ~ 4

Author(s):

Tom Henderson ◽

Roy Rada ◽

Chaomei Chen

Keyword(s):

Collaborative Work ◽

Evaluation Process ◽

Peer Evaluation ◽

State University ◽

Work Skills ◽

Traditional Grading ◽

Washington State University ◽

Peer Evaluations ◽

Course Work ◽

Timely Feedback

Classes delivered via the World Wide Web (WWW) have the ability to access large amounts of hypermedia. They can also be designed to present course work in small, orderly steps. Many learning theorists hypothesize that it is important to provide timely feedback which acts as a reinforcer if answers are good and as a corrective measure if answers are inadequate. However, it may not be practical for an instructor to give timely feedback on each submission done by all students in the class. One possible solution is to combine peer-peer evaluations with timely computer generated reports to help the instructor manage such a course. The peer evaluations may replace some or all of the traditional “grading” done by the professor. This process can contribute to higher developmental levels of understanding and students collaborative work skills may be honed by the requirements of the course. We hypothesize that instructors can adopt graphical methods of data presentation and quality improvement to help monitor the peer evaluation process in a timely and adequate fashion. Three such methods were applied to a class at Washington State University. Pseudo R-charts were used to track when comment scores by peers varied widely on an exercise submission. Pseudo X-bar charts helped identify exercise answers with unusually low average comment scores. Finally, relative frequency histograms were used to compare the frequency of questions asked to the frequency of questions answered when categorized using Bloom's taxonomy. Such tools were used during the class and were valuable input to the instructor.

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Research on Knowledge-Based Virtual Assembly Planning

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.10-12.435 ◽

2007 ◽

Vol 10-12 ◽

pp. 435-439

Author(s):

Bin Wang ◽

D.F. Liu ◽

P. Wang ◽

Q.S. Xie

Keyword(s):

Engineering Design ◽

Virtual Assembly ◽

Assembly Planning ◽

Design Domain ◽

Assembly Rules ◽

Assembly Sequence ◽

Design Environment ◽

Assembly Design ◽

Knowledge Based ◽

Assembly Method

In order to find an optimum assembly sequence in engineering design domain, a knowledge-based virtual assembly approach was put forward. Virtual assembly design environment was also introduced, and knowledge representation models for virtual assembly rules and cases are introduced and studied respectively. A side-center virtual assembly method was applied to avoid the occurrence of assembly interference. Finally, a case was employed to demonstrate the practicality of knowledge-based virtual assembly planning.

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