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 the individual parts and the interactions across the 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 across parts. We demonstrate our system on a wide variety of assemblies.

We analyze a given geometric model of a mechanical assembly to infer how the individual parts move and interact with each other and encode this information as a time-varying interaction graph. once the user indicates a driver part, we use the interaction graph to compute the motion of the assembly and generate an annotated illustration to depict how the assembly works. We also produce a corresponding causal chain sequence to help the viewer mentally animate the motion.

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Illustrating How Mechanical Assemblies Work
Communications of the ACM, January 2013, 56 (1), pp. 106-114.