show that each UAV can communicate with only one IoT system at any given time. In addition, to boost collaboration among the multiple UAVs, any nth IoT machine can be serviced by at most 1 UAV at the same time, represented with the constraint ∑ m χ m n https://gunnerrvzch.tinyblogging.com/aerial-photography-services-bd-things-to-know-before-you-buy-73148010