Abstract:

We present an efficient algorithm for exact calculation and minimization of expected waiting times of all passengers using a bank of elevators. The dynamics of the system are represented by a discrete-state Markov chain embedded in the continuous phase-space diagram of a moving elevator car. The chain is evaluated efficiently using dynamic programming to compute measures of future system performance such as expected waiting time, properly averaged over all possible future scenarios. An elevator group controller based on this method significantly outperforms benchmark algorithms, and although slower than them, is completely within the computational capabilities of currently existing elevator bank controllers.