APPARATUS AND METHOD FOR REPLACING POWER SUPPLY DEVICE IN A UAV

An order fulfillment facility with a delivery system is disclosed having plurality of mobile robots with containers to bring customer orders and/or power supply device/s to UAV/s for final delivery. UAV leaves the discharged power supply devices that are received in empty container and transported to storage area for replenishment and diagnostic checks. Order fulfillment operations along with power supply device charging and monitoring is performed to achieve timely delivery of customer orders.