An international conference connecting people
in CAD research, education and business
Bookmark and Share
Copyright (C) CAD Solutions, LLC. All rights reserved.
Proceedings of CAD'16, 2016, 55-59
Component-based Building Instructions for Block Assembly

Man Zhang, Yoshihiro Kanamori, Jun Mitani, University of Tsukuba
Yuki Igarashi, Meiji University

Abstract. A well-designed set of building instructions is crucial because a LEGO sculpture with fragile constructions of blocks might easily fall to pieces during assembly. To avoid fragmentation during assembly, a smart strategy originating from assembling articulated objects  is to segment a model into solid components, assemble each of them separately, and finally combine them together. However, most block models do not have apparent articulations. For user-friendly assembly, a block model should be divided at weakly-connected blocks, and segmented into as few and as large components as possible to avoid over-segmentation. Also, the preferred assembly orders among LEGO fans seem to be "layer-by-layer and from bottom to top", as these are natural orders for building architecture. However, if building instructions are not carefully designed, some blocks might have neither upward nor downward connections during assembly. Such physically-impossible blocks, defined as floating blocks, are not rare in instructions generated by existing LEGO design systems.

Keywords. LEGO, block assembly, building instructions, segmentation

DOI: 10.14733/cadconfP.2016.55-59