Virtual cellular manufacturing. Relevance and development of heuristics for family-based dispatching

PhD ceremony: Mr. G. Nomden, 14.45 uur, Academiegebouw, Broerstraat 5, Groningen

Title: Virtual cellular manufacturing. Relevance and development of heuristics for family-based dispatching

Promotor(s): prof. G.J.C. Gaalman, prof.dr J. Slomp

Faculty: Economics and Business

Is it possible to achieve short throughput times in small-batch parts manufacturing operations? Even when a high variety of parts is required, in fluctuating volumes, and with a low to medium annual demand? Virtual Cellular Manufacturing may be one of the answers to the challenges that parts manufacturers face, as the research in this thesis shows.

Virtual cells are groups of resources (e.g. machines, workers), each dedicated to the manufacturing of a part family. These virtual cells help to realise the favourable throughput time performance of conventional manufacturing cells. However, the cells are only formed virtually in the planning and control system. Therefore they can relatively easily be adapted to changed circumstances, without the need for expensive layout changes on the shop floor.

The first part of this thesis focuses on the exploration of the relevant literature on Virtual Cellular Manufacturing. Next, three case studies show the applicability of Virtual Cellular Manufacturing in a practical context. The second part presents three simulation studies of family-based dispatching heuristics (one specific implementation of Virtual Cellular Manufacturing) in basic, but realistic, shop configurations. The results show that family-based dispatching heuristics can achieve significant reductions of throughput times. The findings of this thesis may therefore be relevant to many small-batch discrete parts manufacturing companies.