  In this paper, the supervisory control of a Discrete Event System (DES)
analyses states and events to construct an autonomous package delivery system.
The delivery system includes a legged robot in order to autonomously navigate
uneven indoor terrain and a conveyor belt for transporting the package to the
legged robot.The aim of the paper is using the theory of supervisory control of
DES to supervise and control machine's state and event and ensure robots
autonomously collaborate. By applying the theory, we show the collaboration of
two individual robots to deliver goods in a multi-floor environment. The
obtained results from the theory of supervisory control are implemented and
verified in a simulation environment.
