A multi-user selective undo/redo approach for collaborative CAD systems. Issue 2 (1st April 2014)

• Record Type: Journal Article
• Authors: Cheng, Yuan; He, Fazhi; Xu, Bin; Han, Soonhung; Cai, Xiantao; Chen, Yilin
• Is Part Of: Journal of computational design and engineering. Volume 1:Issue 2(2014)
• Page Start: 103
• Page End: 115
• Publication Date: 2014-04-01
• Subjects: Undo/Redo -- Collaborative CAD -- Intention preservation -- Configuration management; Engineering -- Data processing -- Periodicals; Computer-aided design -- Periodicals; Computer-aided design; Engineering -- Data processing; Electronic journals; Electronic journals; Periodicals; 620.0042
• DOI: 10.7315/JCDE.2014.011
• Languages: English
• ISSNs: 2288-4300

Abstract

Abstract: The engineering design process is a creative process, and the designers must repeatedly apply Undo/Redo operations to modify CAD models to explore new solutions. Undo/Redo has become one of most important functions in interactive graphics and CAD systems. Undo/Redo in a collaborative CAD system is also very helpful for collaborative awareness among a group of cooperative designers to eliminate misunderstanding and to recover from design error. However, Undo/Redo in a collaborative CAD system is much more complicated. This is because a single erroneous operation is propagated to other remote sites, and operations are interleaved at different sites. This paper presents a multi-user selective Undo/Redo approach in full distributed collaborative CAD systems. We use site ID and State Vectors to locate the Undo/Redo target at each site. By analyzing the composition of the complex CAD model, a tree-like structure called Feature Combination Hierarchy is presented to describe the decomposition of a CAD model. Based on this structure, the dependency relationship among features is clarified. B-Rep re-evaluation is simplified with the assistance of the Feature Combination Hierarchy. It can be proven that the proposed Undo/Redo approach satisfies the intention preservation and consistency maintenance correctness criteria for collaborative systems.