We have built a working model of the Optimal Elevator Control System. This system consists of an Elevator with four states i.e. Ground floor, 1st floor, 2nd floor, and 3rd floor. We have 4 call buttons which are present outside each floor, and 4 destination buttons which are all present inside the Elevator, along with a fan installed. There is a Close button inside the elevator which forcefully closes the elevator. All the 8 call and destination buttons (together called request buttons), close button, fan, and the states of the elevator are represented by LEDs.

Features of the Elevator Control System : 

• When a request button is pressed it will stay active (the request is still pending) until the Elevator reaches the corresponding floor. • If the Elevator has to change states to satisfy the request, it will either move 1 floor above or below in 2 seconds (clock cycle), depending on the request. 

• At any moment of time, when any set of request buttons are active the Elevator takes the next step in a path which requires least amount of time to satisfy all the request buttons. i.e. It takes the optimal path, minimizing ”time” parameter.

• Whenever elevator satisfies a request or when someone presses and releases the button representing i th floor at a time when elevator is itself at i th floor, then the elevator will open to let the user in and close automatically after 4 sec. The person may press and release that button continuously to hold the elevator for longer period of time. 

• Whenever the elevator is open, person inside the elevator can press the Close button to instantly close the elevator. 

• If one or more destination buttons are active, then the fan will switch ON, else will remain OFF. This not only automates the fan but also acts as an indicator to the person inside the Elevator that a destination button has been recorded or not.