Illustrating How Mechanical Assemblies Work

Niloy J. Mitra, Yong-Liang Yang, Dong-Ming Yan, Wilmot Li, Maneesh Agrawala


How things work visualizations use a variety of visual techniques to depict the operation of complex mechanical assemblies. We present an automated approach for generating such visualizations. Starting with a 3D CAD model of an assembly, we first infer the motions of individual parts and the interactions between parts based on their geometry and a few user specified constraints. We then use this information to generate visualizations that incorporate motion arrows, frame sequences and animation to convey the causal chain of motions and mechanical interactions between parts. We present results for a wide variety of assemblies.

Given a geometric model of a mechanical assembly, we analyze it to infer how the individual parts move and interact with each other. The relations and motion parameters are encoded as a time-varying motiongraph. Once the driver is indicated by the user, we compute the motion of the assembly and use it to generate an annotated illustration to depict how the assembly works. We also produce a corresponding causal chain sequence to help the viewer better mentally animate the motion.

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Illustrating How Mechanical Assemblies Work
SIGGRAPH 2010. July 2010. 58:1-58:12.