Energy-constrained multi-visit TSP with multiple drones considering non-customer rendezvous locations

•We study a multi-visit traveling salesman problem with multiple drones.•Drone energy consumption in all phases of flight is considered to plan drone trips.•We propose a subproblem to locate candidate non-customer retrieval nodes for drones.•MILP formulations are developed for the proposed subproblem and problem.•Effective heuristic and matheuristic solution approaches are provided for problems.