Augmented Reality Anywhere and Anytime
The Handheld Augmented Reality
Come to ISMAR 2011
Compact Presentation of Explosion Diagrams
Inspired by handmade explosion diagrams, our renderings demonstrate the assembly of a set of similar groups of parts by rendering an exploded view only for a single representative. These images are renderings created using our system, which uses only unmodified 3d CAD geometry as input.
Illustrations of compact explosion diagrams rendered with our system. Note how the dimensions of the explosion diagram are reduced in the top left image. The bottom image additionally shows automatically generated views on small or occluded parts.
The figure at the bottom illustrates the main modules of our system, which are used to render a multi-perspective compact explosion diagram from a single point of view.
Initially, an input assembly is fully exploded (A). The system identifies similar parts of the assembly by employing a 3d shape descriptor and ensures that these similar parts are exploded in similar ways. The search for similar parts is further extended to find similar groups of parts (B). The determined similar subassemblies are incorporated into the explosion layout generation, to ensure that also similar groups of parts are exploded in the similar ways.
From the set of similar groups, a representative is selected (C) depending on a quality evaluation of its potential exploded view, including parameters such as their visibility, their size after 2D projection and the angle between explosion direction and the view vector. Moreover, our system takes into account visibility information of the remaining unexploded assemblies. This allows rendering a balanced compact explosion diagram, consisting of a clear presentation of both the exploded representatives and the unexploded remaining assemblies. Since representatives may interfere with one another, our system optimizes combinations of representatives using the approach of threshold accepting.
To increase the effectiveness of the explosion diagrams, our system detects hardly visibly explosions of subassemblies (D) and renders these from more suitable points of view (E). We relate the additional renderings as annotations to their corresponding subassemblies within the main presentation of the explosion diagram. To decrease the amount of annotations, we combine annotations to similar subassemblies into a single annotation for multiple subassemblies. The additional renderings are presented as annotations of the compact explosion diagrams.
A last module, which is not visualized in the graphic, then renders the explosion diagram from the most effective point of view. For this purpose, we compute an explosion diagram from viewpoints lying on the bounding sphere of the exploded object and computing the quality of each viewpoint using the previously mentioned quality parameters. Finally, we select the one with the highest score. Furthermore, we support canonical views and favor points of view which face the object from an elevation below 45° and an azimuth angle which is less than 45°.
The creation of an optimized explosion diagram is a computationally expensive task. Therefore, the presented system currently creates static illustrations of compact explosion diagrams. However, we are extending the system so that compact explosion diagrams can be applied in real-time Augmented Reality applications.
Modules of the system for calculating multi-perspective compact explosion diagrams.
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