Cyclic scheduling of multiple tours with multiple frequencies for a single vehicle

This paper discusses a cyclic scheduling problem arising in cyclic inventory routing, in which a single vehicle has to make multiple tours with different frequencies. The objective is to find a minimal makespan schedule in which the vehicle never travels more than 8 hours per day [and] all tours are repeated with constant intervals. A mathematical model and a best‐fit insertion heuristic are presented for this problem. Computational experiments show that the heuristic finds the optimal solution for 79 out of 100 randomly generated test instances.