Interlocking problems in disassembly sequence planning

Abstract

Remanufacturing is the rebuilding of a product to specifications of the original manufactured product using a combination of directly reused, repaired and new parts. Disassembly, the first and arguably most important process in remanufacturing, tends to be labour-intensive due to complexities in the conditions of end-of-life products returned for remanufacture. Robotic disassembly is an attractive alternative to manual disassembly but robotic systems cannot plan disassembly sequences automatically and manual planning is still necessary. Planning requires machines to interpret physical space using a suitable representation to reflect physical contacts and constraints as well as rules for deciding the sequences of disassembly operations. This paper proposes a representation to describe physical contacts and constraints, and a new approach allowing machines to plan disassembly using the representation. The approach involves employing an assembly matrix and simple logic gates to generate a contact matrix, a space interference matrix and a relation matrix. Rules and algorithms are discussed to explain the calculation of sequences through manipulating the three matrices. A key benefit is that the proposed method can deal with interlocked mechanical structures which cannot be handled using conventional methods. The proposed method is also flexible and is suitable for either selective or complete disassembly.

KEYWORDS:

• Remanufacturing
• disassembly planning
• dismantling
• robotic disassembly
• Sequence planning

Acknowledgements

This paper is an extended version of the article ‘Automatic Detection of Subassemblies for Disassembly Sequence Planning‘ published In Proceedings of the 15th International Conference on Informatics in Control, Automation and Robotics (1), pp. 104-110, 2018. The authors acknowledge Dr Yuanjun Laili, Beihang University, for her comments on the research.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research is supported by the EPSRC (grant number EP/N018524/1), the Royal Society (grant number IEC∖NSFC∖181018) and the National Science Foundation of China (grant number 51775399).