Abstract: While manufacturing systems become more and more automated and robotized, full automation and robotization is unlikely to be achieved in the near future in many industries. Besides, many robot’s characteristics are similar to those of a human operator. We shall consider decision aspects of the workforce employment in the design, reconfiguration and operation of various manufacturing systems, analyse the relevant literature and determine the current research trends. The core object of this presentation is a generic manufacturing problem involving the workforce decisions. It can be formulated as follows.
There is an existing manufacturing system or a manufacturing system to be designed. A physical layout and a working equipment can be given, or they have to be decided within the same manufacturing system type. The traditional manufacturing types are dedicated manufacturing systems, mixed and multi-model assembly lines, flexible manufacturing systems, cellular and seru manufacturing systems and reconfigurable manufacturing systems. If the equipment decision depends on the product demand, then it is a part of the system reconfiguration.
The incoming sequences of (blank) product units can be repetitive or not, and they can be specified or decided. Each product unit requires a set of tasks to be performed by the system. A technological process is given which describes relations between the tasks in space and time. Each task can require additional resources, which can be homogeneous or non-homogeneous, resumable or non-resumable, discrete or continuous, constrained or unconstrained, associated with a cost and/or a priority, etc. Workforce is one of the resources. Its specificity is that it is discrete, dynamic, constrained, high-cost and high-priority.
The workforce is usually categorized into utility, temporary, walking, single-skilled, multi-skilled (cross-trained) workers, and bucket brigades. The most general decision problem is to determine a physical layout of the production system, a tooling equipment, a product flow, an assignment of the tasks to the working equipment, and an allocation of the additional resources so that one or several criteria are addressed. The decisions can be dynamic, that is, time dependent.
The traditional criteria are minimizing the maximum cycle time or maximizing the system productivity in the case of repetitive production, minimizing a function of product completion times in the in case of non-repetitive production, and minimizing the costs of the main equipment and the additional resources. The traditional criteria associated with the workforce are minimizing the maximum number of workers in each production cycle, minimizing the labour costs, minimizing the ergonomic risks, minimizing the maximum workload, maximizing the work variability, and minimizing the maximum or total travelling distance of the workers.
Biography:
Professor Mikhail Y. Kovalyov is a deputy general director for research of the United Institute of Informatics Problems (Minsk, Belarus) and corresponding member of the National Academy of Sciences of Belarus. He contributed to the theory of fully polynomial time approximation schemes, scheduling, production research, computational complexity, algorithm design, logistics, bio-informatics. He published in top Operational Research, Computer Science and Industrial Research journals. He is involved in the editorial work of the journals Computers and Operations Research, European Journal of Operational Research, INFORMS Journal on Computing, Omega and Journal of Scheduling.
