Most people have experienced the difficulties that arise when linebalancing has not
been achieved. Think of the times you could not get on a bus because it was crowded
by people who had boarded at earlier stops. The problems of linebalancing are
common and should be wellknown to all systems designers.
The solution to the linebalancing problem is to control the "empties", to make sure that
there is enough space available, at the right time, to all users of the system. Specifically
for the fully automated baggage system originally planned for Denver, the crux of the
solution is to devise control systems that will deliver enough empty carts to all the
conveyor belts delivering bags to the system