Design and evaluation of a multi-trip delivery model with truck and drones

We extend the Traveling Repairman Problem (TRP) by assuming a single truck which can stop at customer locations and launch drones multiple times from each stop location to serve customers. The problem is mathematically modeled, several bound analyses are conducted to determine the maximum possible improvements in customer waiting times, and an efficient hybrid Tabu Search-Simulated Annealing algorithm is developed to solve the problem. The results of evaluations on several problem instances suggest that the system can yield considerable reductions in customer waiting time for a wide range of model parameters compared to the conventional delivery models.