A multi-criteria approach for a tasks allocation problem with consideration of equity between operators

In this paper, we address the problem of allocating a set of tasks to a set of operators, in labor intensive work environments such as manufacturing of clothing, in order to maximize the performance of the production system. First, we model the problem as a mixed integer problem by adopting the point of view of the company through a goal programming approach. Two objectives are considered: minimizing the total production time and maximizing the quality of products. A critical analysis of the results shows an imbalance in the workload distribution among operators. This analysis led us to propose an approach which takes into account the workload balancing among operators. We study two types of balancing: (1) balancing in terms of temporal loads and (2) balancing in terms of assigned tasks’ number. The result is an integrated model allowing decision makers to find the best compromise between the company's total performance in terms of production time and quality, and the interest of operators in terms of workload. This integrated model was developed and implemented as a decision-making tool that helps companies to make decisions about training of operators.