Patent · US Expired

Queue based elevator dispatching system using peak period traffic prediction

US4838384A · kind A · utility

51Cited by
26References
27Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 21, 1988
Grant dateJun 13, 1989
Priority date
Expiry dateJun 21, 2008

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB66B2201/403
  • WIPO fieldHandling
  • WIPO sectorMechanical engineering

Abstract

Elevator system with multiple cars (1-4) and a group controller (32) having signal processing means (CPU) controlling car dispatching from the lobby (L). During peak conditions (up-peak, down-peak and noontime), each car is dispatched and assigned to hall call floors having a large predicted number of passengers waiting on priority basis, resulting in queue length and waiting time at the lobby and upper floors being decreased, and system handling capacity increased. Estimations of future traffic flow levels for the floors for five minute intervals are made using traffic levels measured during the past few time intervals on that day as real time predictors, using a linear exponential smoothing model, and traffic levels measured during similar time intervals on previous similar days as historic traffic predictors, using a single exponential smoothing model. Combined prediction is used to assign hall calls to cars on priority basis for those floors having predicted high level of passenger traffic to limit maximum waiting time and car load. Noontime priority scheme is based on multiple queue sizes and percentages of maximum waiting time limits. Different waiting time limits can be used…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.