Abstract: An autonomous fabrication method and system are described. A multi-axis robotic arm having at least one end effector is provided, where the at least one end effector comprises an additive manufacturing (AM) toolhead and a component gripping mechanism. The multi-axis robotic arm is directed to fabricate a first portion of an object in a workspace using the AM toolhead, select a prefabricated part using the component gripping mechanism, place the prefabricated part in a predetermined location of the object, and fabricate a second portion of the object in the workspace using the AM toolhead. The object may be one of an unmanned aerial vehicle and an unmanned ground-based vehicle.