to stop elevators from going to floors with no one in them it would use a motion detector on the inside of the elevator
so if there is no one at all in the elevator and someone presses all the buttons the elevator will cancel the internal buttons pressed if it doesnt detect motion in 10 seconds inside of the elevator
the button to call the elevator on the outside of the elevator on every floor probably does not need motion detectors aimed at the button area the elevator will still respond to go to floor by floor if the button is pressed per floor
THE ELEVATOR ONLY TRAVELS WHEN SOMEONE PRESSES THE BUTTON ON THE INSIDE OF THE ELEVATOR WHEN A MOTION DETECTOR DETERMINES IF SOMEONE IS OCCUPYING THE ELEVATOR
(THIS CAN BE DONE 100% USING A MOTION DETECTOR TO CANCEL THE INTERNAL BUTTONS WHEN THE ELEVATOR DOESNT DETECT ANY MOVEMENT AT ALL INSIDE OF IT FOR 10 SECONDS ITS A PRANK OF SOMEONE PRESSING EVERY BUTTON AND THEN GETTING OFF WHEN THEY ARE THE LAST PERSON THE ELEVATOR)
IT CAN ALSO BE USED WITH REGULAR CAMERA DETECTION USING MOTION
OR IT CAN BE DONE 100% USING A THERMAL IMAGING CAMERA ON THE INSIDE OF THE ELEVATOR TO DETECT IF ANY PEOPLE ARE INSIDE OF THE ELEVATOR