Analytical RTT Estimation of a 3-D Elevator System by Exact Stop Positions - Extension to Multi-floor and Non-uniform Population Applications

Albert Ting Pat So


3-dimensional (3-D) elevator systems will be the industrial trend. Traditionally, designers first perform a calculation on traffic analysis to get an overall concept and then go ahead to carry out simulation to obtain details. This tradition is still maintained throughout the world. In one previous article, a “Scanner” approach was adopted to convert a 2-D or 3-D path of scanning to a 1-dimensional line and a sophisticated origin/destination stops matrix was generated to calculate the round trip time (RTT). A probability matrix was generated with an assumption that only one floor was served in one round trip. In a more recent article, by using order statistics, a method to break down a series of repeatable stops in a 3-D system into several series of non-repeatable stops was developed for easy reasoning by designers. Here, a uniform population distribution of all potential stops and a single floor service were assumed. In this article, by following the concept of the most recent article, RTT calculation could be extended to non-uniform population distribution of stops and multi-floor applications which may be the most general approach to calculate the RTT of a truly 3-D elevator system.

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