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Optimization of the network design of a futur- istic transport system based on moving walk- ways Riccardo Scarinci, Guillaume Lopez, Jianghang Chen, Michel Bier- laire Transport and Mobility Laboratory, EPFL May 2014 Optimization of the network design of a futuristic transport system based on moving walkways May 2014 Transport and Mobility Laboratory, EPFL Optimization of the network design of a futuristic trans- port system based on moving walkways Riccardo Scarinci, Guillaume Lopez, Jianghang Chen, Michel Bierlaire, School of Architecture, Civil and Environmental Engineering (ENAC) Transport and Mobility Laboratory (TRANSP-OR) École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland phone: +41 (0) 21 693 24 08 fax: +41 (0) 21 693 80 60 {riccardo.scarinci,guillaume.lopez,jianghang.chen,michel.bierlaire}@epfl.ch May 2014 Abstract Starting from the assumption of a future where the use of cars will be limited in dense urban areas, and thus streets could be used for innovative transport modes, this project investigates a system based on accelerated moving walkways (AMW). Differently from constant moving walkways, AMW can reach speeds up to 15km/h thanks to an acceleration section. This paper, after a review of existing AMW implementations, presents a description of this system and formulates an optimization problem to identify the optimal design of a network of AMW. Decision variables and parameters are defined for a general scenario, and five criteria are considered for the formulation of the objective function: travel time, discomfort, energy consumption, construction cost and operational cost. The resulting multi-objective mixed integer nonlinear optimization problem is evaluated for the simple case of a single link, and results of optimal speed profiles for different parameter values are presented. A network of accelerated moving walkway in a car-free urban environment may present an innovative solution, and further research at a network level could delineate the system feasibility. Keywords Accelerated moving walkway, network optimization, futuristic transport mode i Optimization of the network design of a futuristic transport system based on moving walkways May 2014 1 Introduction In a hypothetical future where the use of private cars will be limited in dense urban areas, the need of movement will be satisfied by a mix of traditional, innovative and futuristic transport modes. Beside traditional systems like bus, metro, tram and taxi, walking and cycling will play a much more important role in the future, together with innovative systems like bike-sharing and car-sharing. Also futuristic modes of transport will be part of the modal mix of tomorrow. For example, projects of urban cable cars and personal rapid transport systems are increasingly studied as a solution for the future mobility. The focus of this project is another possible futuristic system: an urban network of accelerating moving walkways (AMW). Differently from the traditional constant speed moving walkways (CMW), AMW present an acceleration (deceleration) section at the embarking (disembarking) area that accelerates pedestrians to a speed higher than a CMW in the central section. Examples of accelerating walkways show that the system can reach 12-15 km/h (Kusumaningtyas, 2009), a speed competitive with urban bus and tram services, as well as private cars which travel at an average speed of 15 km/h during peak hours (Browning, 1974). Although several implementation of traditional moving walkways and few trials of accelerating walkways exist, see Section 2, in particular in metro stations, airports and dense urban areas, this project studies and optimizes this system starting from a new radical approach. A future without the use of private cars is assumed, and a network, not only individual paths, of moving walkways is studied as one of the transport systems to be adopted to replace private cars. In this scenario, each road has the possibility to be equipped with an accelerated moving walking, and an extended network could be created. This project aims to design and to optimize a network of AMW, identifying the optimal system characteristics that could satisfy at best the demand. The innovation of this research is the study of the possible application of AMW at a network level, in a scenario where the space nowadays used by traditional mean of transport can be used for different purposes. This research is part of the more wide project Post-Car World (PCW, 2014) with the goal of exploring the future of mobility through the role of the car, where the sociological and urbanistic implications of a network of AMW will be investigated together with technological and transportation aspects. The present paper reports the initial research phases and focuses on the definition of the system variables, the formulation of the optimization problem at a link level considering several aspects like travel time, discomfort, energy consumption, construction cost and operational cost. A review of AMW and CMW implementations is carried out to define the technological assumptions necessary to the mathematical description of the system that will lead at the 1 Optimization of the network design of a futuristic transport system based on moving walkways May 2014 identification of the optimal system design. Section 2 reviews existing implementations of AMW, and Section 3 presents the system descrip- tion and characteristics. The formulation of the optimization problem, and a discussion on the decision variables and parameters is reported in Section 4. The preliminary results at a link level are presented in Section 5, and the case study, that will be investigated in further research is introduced in Section 6. The paper finishes with main conclusions and further work in Section 7. Abbreviations and notation are included at the end. 2 Review of AMW types and existing implementations Although the CMW appears to have found its niche in the transport market, the interest to have a transport system continuously moving at a speed higher than walking pace did not fade. Even since the 1960s, several ideas on how to achieve a higher transport speed have been proposed. In the 1970s and early 1980s, a few of these ideas were made into prototypes and were tested. Although none of them were commercialized, their working principles were later adapted for subsequent Accelerating Moving Walkway (AMW) designs. Prototypes of these later designs were built and tested in the late 1990s and early 2000s. This section first presents the different types of AMW based on the technology used in the acceleration section and then reviews existing case studies. 2.1 Types of AMW Based on the method used to achieve acceleration and deceleration, these systems can generally be categorized into the following four types: in-line belts, sliding parallelograms, sliding pallets and accelerating/decelerating rollers. In-line belts A number of belt conveyors with slightly different speeds are placed one after another, end to end. The in-line belts have increasing speeds at each entrance, such that they accelerate passengers to a high-speed belt conveyor in the middle section. Approaching the exit, another series of belts with decreasing speeds decelerate passengers, see Figure 1(a). This mechanism was used in the Loderway system (Loder, 1998), which was tested for public use in Brisbane Airport, Melbourne Airport and Degraves Street Subway in Melbourne. A similar system, named Speedmove, was also built by Fujitec (Kazuo et al., 2003). 2 Optimization of the network design of a futuristic transport system based on moving walkways May 2014 Figure 1: Accelerated moving walkway types. (a) in-line belts, (b) sliding parallelograms, (c) accelerating/decelerating rollers and (d) sliding pallets. Sliding parallelograms A series of parallelogram pallets form a continuous treadway. At the entrance, the pallets move at a low speed for a short distance. Then, while continuing to move forward, each pallet begins to slide progressively sideways with regard to the pallet behind it. The resultant of the forward moving and the sideway sliding creates an accelerating speed, see Figure 1(b). The pallets will stop sliding sideways once they reach the target high speed. The method is reversed for deceleration at the exit. This mechanism was used in the Dunlop Speedaway (Todd, 1974), which was installed for public trial at the Expo ’70 in Osaka, Japan, and at the Battelle Institute in Geneva, Switzerland. The Mitsubishi Speedwalk (Shirakihara, 1997), which was demonstrated at the Seaside Park in Fukuoka, Japan, also adopted this mechanism. This system uses parallelogram pallets forming an S-shape treadway. At the curves, the sideway sliding and the forward moving of each pallet results in an accelerating or decelerating speed. Accelerating/decelerating rollers In this mechanism, a “carpet” of metal rollers at the entrance accelerates passengers onto a high-speed belt conveyor. Approaching the exit, another series of metal rollers decelerates the passengers, see Figure 1(c). The mechanism was adopted by the Gateway system (Cote and Gempp, 1998), which was installed in 2002 for public demonstration in the Paris Montparnasse metro station. Sliding pallets There are a number of different variations in the way the pallets slide. One system accelerated and 3 Optimization of the network design of a futuristic transport system based on moving walkways May 2014 Figure 2: Accelerated moving walkway real implementations. (a) TurboTrack, Toronto airport and (b) Gateway Paris subway. decelerated individual main pallets by sliding them over continuous auxiliary pallets (Ikizawa et al., 2001). Another design uses an array of pallets that slightly overlap one on top of the previous at the entrance, each of which then progressively slides forward to accelerate passengers (Abe et al., 2001). These two systems were only tested in the factory. The more successful variation is the TurboTrack system (Gonzalez Alemany and Cuello, 2003), which employs auxiliary pallets and main pallets, see Figure 1(d). The auxiliary pallets “hide” underneath the main pallets at the entrance and exit, and progressively extend or retract to accelerate or decelerate the passengers.

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