THE ELEVATOR DISPATCHING PROBLEM: HYBRID SYSTEM MODELING AND RECEDING HORIZON CONTROL

Elevator dispatching is a combinatorially hard problem with many control constraints, time-varying traffic patterns, partial state information, and random effects. We develop a hybrid system model of a building with multiple elevator cars and apply a receding horizon control approach, bypassing some of the problem's complexities. Thus, we obtain a “universal” dispatcher which is robust with respect to changing traffic patterns and avoids the problem of having to switch among different controllers when these patterns change over the course of a day (as currently done). Moreover, simulation results show that the performance of this approach improves upon that of state-of-the-art dispatchers.