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arXiv · 1907.03835

Assembly Planning by Subassembly Decomposition Using Blocking Reduction

James Watson·Tucker Hermans
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Abstract

The sequence in which a complex product is assembled directly impacts the ease and efficiency of the assembly process, whether executed by a human or a robot. A sequence that gives the assembler the greatest freedom of movement is therefore desirable. Our main contribution is an expression of obstruction relationships between parts as a disassembly interference graph (DIG). We validate this heuristic by developing a disassembly sequence planner that partitions assemblies in a way that prioritizes access to parts, resulting in plans that are comparable in efficiency to two state-of-the-art assembly methods in terms of total plan length. Using DIG, our method generates successive subassembly decompositions, yielding a tree structure that makes parallization opportunities apparent. Our planner generates viable disassembly plans by minimizing our part blockage measure, and thereby demonstrates that this measure is a valuable addition to the Assembly Sequence Planning toolkit.

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James Watson, Tucker Hermans. 2019-07-08. Assembly Planning by Subassembly Decomposition Using Blocking Reduction. https://arxiv.org/abs/1907.03835

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