bi-objective approach based on fuzzy logic for multi-period technician routing and scheduling problems
This paper deals with a multi-period technician routing and scheduling problem. The problem carries out the tasks at various locations by being divided into teams considering differently skilled technicians. This paper provides a bi-objective mixed integer programming method to model the problem since the goals of the performed model are to optimize the travel cost while simultaneously minimizing the overtime and the waiting time. The paper introduces a fuzzy logic approach to solving the problem by offering a single Pareto solution to satisfy both objectives, rather than providing efficient solutions as in the case of classical multi-objective models. Furthermore, the problem specifies the division of the technicians of different skills into teams, assigning tasks with varying skill requirements to groups, and the routes for each team simultaneously. Finally, the paper presents the computational experiments and analyses to evaluate the efficiency of the suggested mathematical formulation and solution approach. The results demonstrate that the performed model accomplishes an acceptable satisfaction level.