System and method of asynchronous robotic retrieval and delivery of items

A method comprising:

• receiving, at a depot and via a depot user interface, a specification by a user of a destination depot and an item to yield item delivery data;
• selecting, based on item delivery data and by a depot control system, a drawer from a rack module in the depot that houses drawers;
• receiving the item from the user via the depot user interface;
• transferring the item to the drawer within the rack module that houses drawers;
• communicating, from the depot and to a mobile robot, a message to pick up the item;
• transferring the item from the drawer to the mobile robot using a depot drawer-swapping module and a mobile robot drawer-swapping module;
• and
• delivering, by the mobile robot, the item to the destination depot.

A system comprising:

• a processor;
• and
• a computer-readable storage device storing instructions which, when executed by the processor, cause the processor to perform operations comprising:
• receiving, at a depot and via a depot user interface, a specification by a user of a destination depot and an item to yield item delivery data;
• selecting, based on item delivery data and by a depot control system, a drawer from a rack module in the depot that houses drawers;
• receiving the item from the user via the depot user interface;
• transferring the item to the drawer within the rack module that houses drawers;
• communicating, from the depot and to a mobile robot, a message to pick up the item;
• and
• transferring the item from the drawer to the mobile robot using a depot drawer-swapping module and a mobile robot drawer-swapping module, wherein the mobile robot is configured to deliver the item to the destination depot.