The study on factors affecting the elevator performance in high-rise buildings: A case study at Petronas buildings (Petronas Twin Towers, Vista Tower, and G Tower), Kuala Lumpur / Nuraziemah Mohamad Asli

There are many approached to model an elevator routing system. In this study, some literature is shortly described, wherein different traffic categories and elevator policy types are presented. In the simulation approach, zoning is often used to model the elevator routing system. Zoning means that the floors are split into a number of zones, each consisting of a group of floors. Different zones are served by different elevators. Dynamic zoning can reduce passenger waiting times in high-rise buildings. Therefore, three types of elevator policies are chosen. In the presented model, the elevators of three policies are considered that are carrying passengers from the ground floor to higher floors in PETRONAS Twin Towers, Vista Tower, and G Tower. Four different elevators traffic (up-peak, normal, inter-floor, and down-peak), with three different elevator policies (zoning odd/even, zoning low/high, and no zoning) are compared on their performance (waiting times). Analysing the results tends to the conclusion that using zoning policies in such high-rise buildings is preferable above a policy without zoning. Furthermore, the conclusion that can be made from the results obtained is instead of the other traffic categories, the normal traffic perform the bes

Need a Lift? An Elevator Queueing Problem

Various aspects of the behavior and dispatching of elevators (lifts) were studied. Monte Carlo simulation was used to study the statistics of the several models for the peak demand at uppeak times. Analytical models problems were used to prove or disprove whether schemes were optimal. A mostly integer programming problem was formulated but not studied further

Submodular Function Maximization for Group Elevator Scheduling

We propose a novel approach for group elevator scheduling by formulating it as the maximization of submodular function under a matroid constraint. In particular, we propose to model the total waiting time of passengers using a quadratic Boolean function. The unary and pairwise terms in the function denote the waiting time for single and pairwise allocation of passengers to elevators, respectively. We show that this objective function is submodular. The matroid constraints ensure that every passenger is allocated to exactly one elevator. We use a greedy algorithm to maximize the submodular objective function, and derive provable guarantees on the optimality of the solution. We tested our algorithm using Elevate 8, a commercial-grade elevator simulator that allows simulation with a wide range of elevator settings. We achieve significant improvement over the existing algorithms.Comment: 10 pages; 2017 International Conference on Automated Planning and Scheduling (ICAPS

Performance comparison between TEMO and a typical FMS in presence of CTA and wind uncertainties

© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Best session (Aiport Management & Arrival/Departure operations) paper award - 35th DASC. 2016Continuous Descent Operations (CDO) with Con- trolled Times of Arrival (CTA) at one or several metering fixes could enable environmentally friendly procedures without com- promising airspace capacity. Extending the current capabilities of state-of-the-art Flight Management Systems (FMS), the Time and Energy Managed Operations (TEMO) concept is able to generate optimal descent trajectories with an improved planning and guidance strategy to meet CTA. The primary aim of this paper is to compare the performances of TEMO (in terms of fuel consumption and time error) with respect to a typical FMS, that is an FMS without re-planning mechanism during descent based on time or altitude errors. The comparison is performed through simulation, using an A320-alike simulation model and considering several scenarios in presence of CTA and wind uncertainties. Results show that TEMO is capable of guiding the aircraft along a minimum fuel trajectory still complying with a CTA, even if significant wind prediction errors are present. For a same scenario, a typical FMS without re-planning capabilities or tactical time-error nulling mechanism during the descent, would miss the CTA in most cases.Peer ReviewedAward-winningPostprint (published version

4D Continuous Descent Operations Supported by an Electronic Flight Bag

This paper describes a set of flight simulation experiments carried out with the DLR’s Generic Cockpit Simulator (GECO). A new concept named time and energy managed operations (TEMO), which aims to enable advanced four dimensional (4D) continuous descent operations (CDO), was evaluated after three full days of experiments with qualified pilots. The experiment focused to investigate the possibility of using a 4D-controller on a modern aircraft with unmodified or only slightly modified avionic systems. This was achieved by executing the controller in an Electronic Flight Bag (EFB) and using the pilot to “close the loop” by entering speed and other advisories into the autopilot Flight Control Unit (FCU). The outcome of the experiments include subjective (questionnaires answered by pilots) and objective (trajectory logs) data. Data analysis showed a very good acceptance (both in terms of safety and operability of the procedure) from the participating crews, only with minor suggestions to be improved in future versions of the controller and the speed advisories update rates. Good time accuracy all along the descent trajectory was also observed.Peer ReviewedPostprint (published version

Linear motor for multi-car elevators, design and position measurement

Multi-car elevator is an emerging technology consisting of two or more elevator cars moving independently in an elevator hoistway, which has become more appealing as building heights increase. In this paper, the design and drive methodologies for a linear motor driven multi-car elevator system with independently moving cars is introduced together with experimental results. Additionally, a safety method developed for the linear motor elevator and the conditions necessary for its proper operation are discussed. The new results introduced in this paper are in the areas of the design method of the linear motor for multi-car elevator system, and the preliminary results for the position measurement system

Calculation of the elevator round-trip time under destination group control using offline batch allocations and real-time allocations

The use of Destination Group Control (DGC), or Hall Call Allocation (HCA), in elevator traffic system group control is the current trend in intelligent and advanced supervisory control and expected to dominate the market in the future. In the conventional elevator traffic design process, designers usually start with a simple calculation in order to obtain a conceptual estimate of the suggested design prior to moving onto simulation. But due to the lack of a suitable set of equations for elevator traffic calculation for DGC systems, designers are forced to carry out the elevator traffic design process for a system controlled by DGC solely by using simulation. Due to dependence on the simulator and algorithms it uses, different simulation packages will produce different resultant designs. Thus, the motivation for this paper is to use calculation in order to achieve more transparency and repeatability in the design of DGC systems. In order to enable the designer to carry out a calculation for the DGC system, equations are needed to evaluate the values of H (the highest reversal floor) and S (the expected number of stops in a round trip) in order to evaluate the value of the round-trip time under destination group control. Although equations are available to compute the highest reversal floor, H, and expected number of stops, S, of a DGC system, these equations assume optimal idealized conditions and do not take into consideration the effect of real time allocation of landing calls to elevator cars. If designers use them to design the elevator traffic system, the design will be under-sized and inadequate. They do not take into consideration many of the practical implementation issues and non-ideal conditions such as: unequal floor populations, real time call allocation of calls to elevator cars, and the different floor to sector arrangements, as well as the practicalities of allocating elevator cars to sectors. In this paper, more detailed consideration is given to the estimation of H and S under both offline and real-time call allocations under up-peak traffic conditions. Three methods of sectoring are suggested to take care of different combinations of the number of floors, the number of elevators, the car capacity, and the floor population distribution. Results of this research would help the designer carry out a more reasonable and practical calculation of the round-trip time under DGC and thus arrive at a transparent and repeatable elevator traffic design. The designer is still expected to move on to a simulation phase in order to understand the effect of the group controller on system performance

Flight testing Time and Energy Managed Operations (TEMO)

The expected growth in air traffic combined with an increased public concern for the environment, have forced legislators to rethink the current air traffic system design. The current air traffic system operates at its capacity limits and is expected to lead to increased delays if traffic levels grow even further. Both in the United States and Europe, research projects have been initiated to develop the future Air Transportation System (ATS) to address capacity, and environmental, safety and economic issues. To address the environmental issues during descent and approach, a novel Continuous Descent Operations (CDO) concept, named Time and Energy Managed Operations (TEMO), has been developed co-sponsored by the Clean Sky Joint Undertaking. It uses energy principles to reduce fuel burn, gaseous emissions and noise nuisance whilst maintaining runway capacity. Different from other CDO concepts, TEMO optimizes the descent by using energy management to achieve a continuous engine-idle descent, while satisfying time constraints on both the Initial Approach Fix (IAF) and the runway threshold. As such, TEMO uses timemetering at two control points to facilitate flow management and arrival spacing. TEMO is in line with SESAR step 2 capabilities, since it proposes 4D trajectory management and is aimed at providing significant environmental benefits in the arrival phase without negatively affecting throughput, even in high density and peak-hour operations. In particular, TEMO addresses SESAR operational improvement (OI) TS-103: Controlled Time of Arrival (CTA) through use of datalink [1]. TEMO has been validated starting from initial performance batch studies at Technology Readiness Level (TRL) 3, up to Human-in-the-Loop studies in realistic environments using a moving base flight simulator at TRL 5 ([2]-[6]). In this paper the definition, preparation, performance and analysis of a flight test experiment is described with the objective to demonstrate the ability of the TEMO algorithm to provide accurate and safe aircraft guidance toward the Initial Approach Fix (IAF), and further down to the Stabilization Point (1000 ft AGL), to demonstrate the ability of the TEMO algorithm to meet absolute time requirements at IAF and/or runway threshold and to evaluate the performance of the system under test (e.g. fuel usage).Peer ReviewedPostprint (published version

Time and Energy Managed Operations (TEMO): Cessna Citation II Flight Trials

From 9-26 October 2015 the Netherlands Aerospace Centre (NLR) in cooperation with Delft University of Technology (DUT) has executed Clean Sky flight trials with the Cessna Citation II research aircraft. The trials consisted of several descents and approaches at the Eelde airport near Groningen, demonstrating the TEMO (Time and Energy Managed Operations) concept developed in the Clean Sky Joint Technology Initiative research programme as part of the Systems for Green Operations (SGO) Integrated Technology Demonstrator. A TEMO descent aims to achieve an energy-managed idle-thrust continuous descent operation (CDO) while satisfying ATC time constraints, to maintain runway throughput. An optimal descent plan is calculated with an advanced on-board real-time aircraft trajectory optimisation algorithm considering forecasted weather and aircraft performance. The optimised descent plan was executed using the speed-on-elevator mode of an experimental Fly-By-Wire (FBW) system connected to the pitch servo motor of the Cessna Citation II aircraft. Several TEMO conceptual variants have been flown. It has been demonstrated that the TEMO concept enables arrival with timing errors below 10 seconds. The project was realised with the support of CONCORDE partners Universitat Politècnica de Catalunya (UPC) and PildoLabs from Barcelona, and the Royal Netherlands Meteorological Institute (KNMI).Peer ReviewedPostprint (published version

Genetic algorithm for controllers in elevator groups: analysis and simulation during lunchpeak traffic

The efficient performance of elevator group system controllers becomes a first order necessity when the buildings have a high utilisation ratio of the elevators, such as in professional buildings. We present a genetic algorithm that is compared with traditional controller algorithms in industry applications. An ARENA simulation scenario is created during heavy lunchpeak traffic conditions. The results allow us to affirm that our genetic algorithm reaches a better performance attending to the system waiting times than THV algorithm