A novel multi-objective optimization model for vehicle routing problem with drone delivery and dynamic flight endurance

In these instances, the number of customers is set to 40, 80, 120, and 160 respectively. All customers and depot are located in a square area. The vertical distance from the edge of the area to the center of the area is set to 20 km, 30 km, and 40 km, which represent the three different sizes of square areas respectively. Because the maximum load capacity of drones can not satisfy the demand of all customers in the real world, the percentage of customers that can be served by drones is assumed to be 30%, 50%, and 70% respectively in these instances. Since these instances involve the different types of combinations (the number of customers, the vertical distance from the edges of square area to its center, and the percentage of customers who can be served by drones), they can be simply named intuitively. For example, the instance "40-20-30" means that there are 40 customers located in a square area, the vertical distance from the edge of the area to its center is 20 km, and only 30% of the customers can be served by the drone.