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  • 1.
    Andersson, Malin
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Simuleringsbaserad analys av pendelbåtstrafik i Stockholm2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper analyzes how an agent-based simulation model of Stockholm can be used for water transitplanning. A new route for commuters by boat was added to the model of Stockholm’s existingtransport system and evaluated. By comparing results from the model and statistic data fromTrafikförvaltningen Region Stockholm during the morning rush-hour, a scale factor was calculated.The scale factor was later used to adjust the number of travelers on the added new water transit routeas the model underestimate the number of persons who use the available public transport by boat. Thelarge size of the calculated factor made the results uncertain when trying to predict any effects the newroute would have, e.g. on congestion in the system. Simulations of the new transit line resulted in amajority of short trips, between stations were the other public transit options took longer routes. Thetransit stops close to the city centre were used the most and most trips were conducted between them.To gain an improved ability to simulate water transit, continued studies of people’s preferencesregarding mode choice appear to be crucial.

  • 2.
    Babicheva, Tatiana
    et al.
    VEDECOM, 77 Rue Chantiers, F-78000 Versailles, France..
    Burghout, Wilco
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. VEDECOM, 77 Rue Chantiers, F-78000 Versailles, France..
    Andreasson, Ingmar
    LogistikCtr Goteborg AB, Osbergsgatan 4 A, S-42677 Vastra Frolunda, Sweden..
    Faul, Nadege
    VEDECOM, 77 Rue Chantiers, F-78000 Versailles, France..
    Empty vehicle redistribution and fleet size in autonomous taxi systems2019In: IET Intelligent Transport Systems, ISSN 1751-956X, E-ISSN 1751-9578, Vol. 13, no 4, p. 677-682Article in journal (Refereed)
    Abstract [en]

    This study investigates empty vehicle redistribution algorithms for personal rapid transit and autonomous taxi services. The focus is on passenger service and operator cost. A new redistribution algorithm is presented in this study: index-based redistribution (IBR). IBR is a proactive method, meaning it takes into account both current demand and anticipated future demand, in contrast to reactive methods, which act based on current demand only. From information on currently waiting for passengers, predicted near-future demand and projected arrival of vehicles, IBR calculates an index for each vehicle station, and redistribution is done based on this index. Seven different algorithm combinations are evaluated using a test case in Paris Saclay, France (20 stations and 100 vehicles). A combination of simple nearest neighbours and IBR is shown to be promising. Its results outperform the other methods tested in peak and off-peak demand, in terms of average and maximum passenger waiting times as well as station queue length. The effect of vehicle fleet size on generalised cost is analysed. Waiting times, mileage and fleet size are taken into account while assessing this generalised cost.

  • 3.
    BERG WINCENT, BOEL
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Gångavstånd för resor med elsparkcykel: En studie baserat på elsparkcykelaktören Voi Technology i Stockholm2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Electric scooters, or e-scooters as they also are called, were launched in California in USA as a bike share system, in 2017. A year later, in September 2018, the Swedish company Voi Technology launched the first e-scooters in Stockholm, Sweden. Bike share systems has been around since the 1960s but has grown substantially in the past 15 years. New technical solutions have solved past problems with theft and payment in bike shares. Since e-scooters are new, there is a lack of research and knowledge about practical use. The study aims to examine how long users of e-scooters walk to utilize the service. Travel data from Voi Technology is used to determine walking distance. The distance from the location where the app was opened to the location where the e-scooter trip begun was measured. The result was also compared the walking distance of other bike share systems and travelers of public transportation. The majority of e-scooter users walk less than 100 meters and 38 per cent walk less than 50 meters. The users have the shortest walking distance in the morning and the longest in the afternoon. During the weekend's users walk further than in weekdays. The users who travel longer distances with the e-scooters don’t walk further than other users. About a third of the users walk in the opposite direction of travel, to some extent, to catch an e-scooter. That indicates that the aim of the user in general seems to be to always have the shortest possible walking distance to the e-scooter.

  • 4.
    Cebecauer, Matej
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Short-Term Traffic Prediction in Large-Scale Urban Networks2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    City-wide travel time prediction in real-time is an important enabler for efficient use of the road network. It can be used in traveler information to enable more efficient routing of individual vehicles as well as decision support for traffic management applications such as directed information campaigns or incident management. 3D speed maps have been shown to be a promising methodology for revealing day-to-day regularities of city-level travel times and possibly also for short-term prediction. In this paper, we aim to further evaluate and benchmark the use of 3D speed maps for short-term travel time prediction and to enable scenario-based evaluation of traffic management actions we also evaluate the framework for traffic flow prediction. The 3D speed map methodology is adapted to short-term prediction and benchmarked against historical mean as well as against Probabilistic Principal Component Analysis (PPCA). The benchmarking and analysis are made using one year of travel time and traffic flow data for the city of Stockholm, Sweden. The result of the case study shows very promising results of the 3D speed map methodology for short-term prediction of both travel times and traffic flows. The modified version of the 3D speed map prediction outperforms the historical mean prediction as well as the PPCA method. Further work includes an extended evaluation of the method for different conditions in terms of underlying sensor infrastructure, preprocessing and spatio-temporal aggregation as well as benchmarking against other prediction methods.

  • 5.
    Cebecauer, Matej
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Gundlegård, David
    Department of Science and Technology,Linköping University.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Burghout, Wilco
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    3D Speed Maps and Mean Observations Vectors for Short-Term Urban Traffic Prediction2019In: TRB Annual Meeting Online, Washington DC, US, 2019, p. 1-20Conference paper (Refereed)
    Abstract [en]

    City-wide travel time prediction in real-time is an important enabler for efficient use of the road network. It can be used in traveler information to enable more efficient routing of individual vehicles as well as decision support for traffic management applications such as directed information campaigns or incident management. 3D speed maps have been shown to be a promising methodology for revealing day-to-day regularities of city-level travel times and possibly also for short-term prediction. In this paper, we aim to further evaluate and benchmark the use of 3D speed maps for short-term travel time prediction and to enable scenario-based evaluation of traffic management actions we also evaluate the framework for traffic flow prediction. The 3D speed map methodology is adapted to short-term prediction and benchmarked against historical mean as well as against Probabilistic Principal Component Analysis (PPCA). The benchmarking and analysis are made using one year of travel time and traffic flow data for the city of Stockholm, Sweden. The result of the case study shows very promising results of the 3D speed map methodology for short-term prediction of both travel times and traffic flows. The modified version of the 3D speed map prediction outperforms the historical mean prediction as well as the PPCA method. Further work includes an extended evaluation of the method for different conditions in terms of underlying sensor infrastructure, preprocessing and spatio-temporal aggregation as well as benchmarking against other prediction methods.

  • 6.
    Cebecauer, Matej
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Burghout, Wilco
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Integrated framework for real-time urban network travel time prediction on sparse probe data2018In: IET Intelligent Transport Systems, ISSN 1751-956X, E-ISSN 1751-9578, Vol. 12, no 1, p. 66-74Article in journal (Refereed)
    Abstract [en]

    The study presents the methodology and system architecture of an integrated urban road network travel time prediction framework based on low-frequency probe vehicle data. Intended applications include real-time network traffic management, vehicle routing and information provision. The framework integrates methods for receiving a stream of probe vehicle data, map matching and path inference, link travel time estimation, calibration of prediction model parameters and network travel time prediction in real time. The system design satisfies three crucial aspects: computational efficiency of prediction, internal consistency between components and robustness against noisy and missing data. Prediction is based on a multivariate hybrid method of probabilistic principal component analysis, which captures global correlation patterns between links and time intervals, and local smoothing, which considers local correlations among neighbouring links. Computational experiments for the road network of Stockholm, Sweden and probe data from taxis show that the system provides high accuracy for both peak and off-peak traffic conditions. The computational efficiency of the framework makes it capable of real-time prediction for large-scale networks. For links with large speed variations between days, prediction significantly outperforms the historical mean. Furthermore, prediction is reliable also for links with high proportions of missing data.

  • 7.
    Cebecauer, Matej
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Burghout, Wilco
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Spatio-Temporal Partitioning of Large Urban Networks for Travel Time Prediction2018In: 2018 21ST INTERNATIONAL CONFERENCE ON INTELLIGENT TRANSPORTATION SYSTEMS (ITSC), IEEE , 2018, p. 1390-1395Conference paper (Refereed)
    Abstract [en]

    The paper explores the potential of spatiotemporal network partitioning for travel time prediction accuracy and computational costs in the context of large-scale urban road networks (including motorways/freeways, arterials and urban streets). Forecasting in this context is challenging due to the complexity, heterogeneity, noisy data, unexpected events and the size of the traffic network. The proposed spatio-temporal network partitioning methodology is versatile, and can be applied for any source of travel time data and multivariate travel time prediction method. A case study of Stockholm, Sweden considers a network exceeding 11,000 links and uses taxi probe data as the source of travel times data. To predict the travel times the Probabilistic Principal Component Analysis (PPCA) is used. Results show that the spatio-temporal network partitioning provides a more appropriate bias-variance tradeoff, and that prediction accuracy and computational costs are improved by considering the proper number of clusters towards robust large-scale travel time prediction.

  • 8.
    Fröidh, Oskar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Berg, Mats
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Rail Vehicles.
    Framtida trafikeringskostnader och utveckling av persontågsparken: Slutrapport2019Report (Other academic)
    Abstract [sv]

    Syftet med projektet och rapporten är att beräkna och redovisa trafikeringskostnader med typtåg som underlag för ASEK 7.0 i Trafikverkets kommande nationella trafik- och infrastrukturplanering, och att göra en bedömning av vilka framtida tågtyper som kan rulla på spåren.

    Projektets resultat är främst val av typtåg och de trafikeringskostnader för typtågen som presenteras i rapporten.

    En äldre modell för att beräkna trafikeringskostnader i persontrafik har uppdaterats och vidareutvecklats vid KTH till Costmodel PT. Denna modell har använts att beräkna kostnader för framtida typtåg. I vissa fall saknas motsvarande tågtyp i Sverige idag och det har också varit svårt att få tillgång till aktuella data genom kommersiell sekretess. Trots det har den kalibrering som gjorts mot tillgängliga verkliga värden visat på en relativt god överensstämmelse.

  • 9.
    Jin, Junchen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. Enjoyor Co Ltd, Hangzhou 310030, Zhejiang, Peoples R China.
    Ma, Xiaoliang
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    A non-parametric Bayesian framework for traffic-state estimation at signalized intersections2019In: Information Sciences, ISSN 0020-0255, E-ISSN 1872-6291, Vol. 498, p. 21-40Article in journal (Refereed)
    Abstract [en]

    An accurate and practical traffic-state estimation (TSE) method for signalized intersections plays an important role in real-time operations to facilitate efficient traffic management. This paper presents a generalized modeling framework for estimating traffic states at signalized intersections. The framework is non-parametric and data-driven, without any requirement on explicit modeling of traffic flow. The Bayesian filter (BF) approach is the core of the framework and introduces a recursive state estimation process. The required transition and measurement models of the BFs are trained using Gaussian process (GP) regression models with respect to a historical dataset. In addition to the detailed derivation of the integration of BFs and GP regression models, an algorithm based on the extended Kalman filter is presented for real-time traffic estimation. The effectiveness of the proposed framework is demonstrated through several numerical experiments using data generated in microscopic traffic simulations. Both fixed-location data (i.e., loop detector) and mobile data (i.e., connected vehicle) are examined with the framework. As a result, the method shows good performance under the different traffic conditions in the experiment. In particular, the approach is suitable for short-term estimation, a challenging task in traffic control and operations.

  • 10.
    Langbroek, Joram H. M.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment. KTH, School of Industrial Engineering and Management (ITM), Centres, Integrated Transport Research Lab, ITRL.
    Cebecauer, Matej
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Malmsten, Jon
    Franklin, Joel P.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment.
    Susilo, Yusak O.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment.
    Georén, Peter
    KTH, School of Industrial Engineering and Management (ITM), Centres, Integrated Transport Research Lab, ITRL. Solkompaniet Sverige AB, Vastbergavagen 4, S-12630 Hagersten, Sweden..
    Electric vehicle rental and electric vehicle adoption2019In: Research in Transportation Economics, ISSN 0739-8859, E-ISSN 1875-7979, Vol. 73, p. 72-82Article in journal (Refereed)
    Abstract [en]

    This case study describes the project Elbilsiandet (The Electric Vehicle Country) in Gotland, Sweden, where the island Gotland is made "ready for electric vehicles" by providing a network of charging infrastructure and electric vehicle rental during several summer seasons. The influence of the electric vehicle (EV) rental scheme on the process towards electric vehicle adoption is investigated using the Protection Motivation Theory (PMT) and the Transtheoretical Model of Change (TTM). Moreover, the travel patterns of electric rental cars are compared with those of conventional rental cars. The main results of this study are the following: Firstly, people renting an EV are on average closer to electric vehicle adoption than people renting a conventional vehicle. Secondly, people who rent an EV are at the time of rental associated with more positive attitudes towards EVs, have more knowledge about EVs and would feel more secure driving an EV. Thirdly, EV-rental does not seem to have a large additional effect on the stage-of-change towards EV-adoption of the participants. Lastly, the driving patterns of EVs do not seem to indicate serious limitations regarding driving distance, parking time and the destinations that have been visited, as compared to the driving patterns of conventional rental cars.

  • 11.
    Leffler, David
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Simulation based evaluation of flexible transit2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Transport authorities are faced with the challenge of making effective use of existing transportation infrastructure under increasing needs of transport accessibility, sustainability, and safety. The ongoing growth and adoption of shared mobility options, the anticipation of automated vehicles, and the increased availability of real-time data brought on with the developments of Intelligent Transport Systems, have all inspired many innovations in public transit design. The integration of these technologies in existing public transit holds great potential for operational planning and control, but is also notoriously difficult to evaluate. In the included papers, flexible operational policies that make use of real-time data and connected vehicles are developed and assessed through the extension of an existing public transit simulation framework, BusMezzo.

    Paper I explores the incorporation of flexibility in fixed urban transit via real-time short-turning, a fleet management strategy not often studied in a real-time context. In this paper, a decision rule for when and where a short-turn should occur based on predicted passenger costs is developed and evaluated in a case study of a bidirectional urban bus line in Stockholm, Sweden.

    Paper II focuses on the design and analysis of an automated feeder service. In this paper an extension of BusMezzo with a module for simulating a variety of flexible transit operations is presented. Estimated reductions in on-board crew costs with vehicle automation motivate a case study of two vehicle fleets where a fully demand-responsive operational policy is compared against fixed route and schedule operations.

  • 12.
    Leffler, David
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Cats, Oded
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. Delft University of Technology, Netherlands.
    Burghout, Wilco
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Simulation of fixed versus on-demand station-based feeder operationsManuscript (preprint) (Other academic)
    Abstract [en]

    Motivated by lower predicted operational costs, and opportunities for efficient real-time control, automated, centrally coordinated vehicles have in many studies shown great potential as a shared resource within public transit. One particular use case that has grown in popularity over recent years is the application of smaller, automated shuttles as an on-demand feeder to mass transit solution. To investigate differences in fixed versus on-demand operational policies, this paper discusses the operational design and analysis of an automated feeder solution. To this end, a simulation model of demand-responsive transit is developed and incorporated into the transit simulation model BusMezzo. An estimation of operational cost reductions with vehicle automation motivates the case study of two fleets that are deemed comparable with respect to service capacity and operational cost per hour. Results from simulation studies of varying levels of demand indicate that the on-demand policy reduces average total passenger travel times and, for the larger fleet, lowers average vehicle-kilometers traveled per passenger relative fixed service operations. Without achieving a competitive reduction in waiting times, however, on-demand coordination often underperforms with respect to level-of-service and reliability when compared with fixed service operations. When there is slack in fixed service capacity, the performance of the on-demand service outperforms the fixed service with respect to both level-of-service and vehicle utilization only for the lowest demand level tested and the smaller fleet. Average total system costs under on-demand operations improve, however, for the lowest demand levels and the larger fleet due to a reduction in vehicle-kilometers traveled relative a fixed service. When fixed service capacity is exceeded it is found that on-demand coordination outperforms fixed operations with respect to average level-of-service, vehicle-kilometers traveled, and total system costs. Furthermore, when planned service capacity is exceeded, it is found that total passenger waiting time is more equally distributed under on-demand operations relative to fixed.

  • 13.
    LIDSTRÖM OLSSON, DANIEL
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Inlandsbanan – befintliga spår, ny trafik: Förutsättningar för regional spårtrafik i glesbebyggda områden2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When the car dependency grew under many decades in Sweden parts of the rail network was shutdown or got reduced traffic due to the diminishing demand for rail travel. The railway lines affectedwere primarily those in rural areas with an already low number of travellers. One of these linesthreatened to be shut down was the line called Inlandsbanan (Inland line). Inlandsbanan was savedby the municipalities located along the line who now manage the railway by a co-owned company.Since the railway became managed by the co-owned company the railway has mostly been used fortourist-oriented traffic and freight traffic.Today the conditions are different, the demand for rail travel has increased due to a general highertransport demand and an increased environmental awareness. This study has been carried out tofind out if there is possibility to re-establish regional rail traffic for passengers on Inlandsbanan.The study has been carried out using statistics of current travel volumes and inhabitants in thepopulation centres along the line. This data has been analysed with support from earlier studiesregarding regional rail traffic and public transport in rural areas. As an extra tool in the study asimulation program has been used to estimate the travel demand for the line.The study found that the current low speed on Inlandsbanan is the biggest obstacle for implementingan attractive regional rail service on the line. The train is too slow in comparison to the car andtherefore it is not able to gain any considerable share of the total amount of travellers. It is possibleto replace regional bus service at some parts of the line since the train has some minor time gaincompared to the current bus service and the train could also offer a higher level of comfort.

  • 14.
    Rickardsson, Johan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Olofsson, Josefin
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Att utforma en gång- och cykelbana: En analys av utrymmesbehovet på ytbegränsade gång- och cykelbanor i Stockholm2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Region Stockholm recently set a goal to highly increase the bicycle traffic share the comingdecade. Bicycles as a means of transport has grown in popularity and current trends showa steady yearly increase. The ambitiously set goal puts high demands on the currentpedestrian and bicycle paths in the city. More often than not, pedestrians and cyclists sharethe same space, and thus creating a source for conflicts. Accident statistics show these twogroups are particularily vulnerable, and as a result there is a considerable need for gooddesign of pedestrian and bicycle paths.The aims of this study are to examine the current guiding manuals for design; to developand use a method of analysing the interactions between pedestrians and cyclists; andfinally to explore how the design recommendations from the guiding manuals are followedthroughout routes in the city. The study’s purpose could be summarised as investigatingwhich widths of the pedestrian and bicycle paths result in the smallest amount of conflictsbetween the two groups. The project is split into one part literature study, one part fieldstudy.The literature study scrutinises the guiding manuals for design published by RegionStockholm, The Swedish Transport Administration ( Trafikverket ), The City of Stockholm,and The Swedish Authority of Local Authorities and Regions ( SKL ). Other works, such asreports and papers, or guiding design manuals from Denmark, a country in the frontier ofbicycle planning, are included in the analysis. In the field study, nine suitable locations inStockholm are chosen for data collection. The number of interactions and conflictsbetween pedestrians and cyclists are analysed for each location with intention of findingconnections between the conflicts and the design of the pedestrian and bicycle paths.Ultimately the study concludes that pedestrian paths should have a minimum width of 210centimetres. A satisfying interval of 220 - 230 centimetres is shown to be sufficient as thewidth of the bicycle path, which in total adds up to about 4.3 metres.

  • 15.
    Zhang, Wei
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Planning and evaluation of autonomous vehicles in freight and public transport services2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The introduction of automation technology in transport systems brings both opportunities and challenges. The direct benefits of automation technology are obvious, for instance, reduced marginal driving cost, improved energy efficiency and increased safety. However, factors such as additional vehicle acquisition cost might hinder the implementation of autonomous vehicles, especially in the early stages when mass production is not realized yet. Besides, some benefits require large-scale applications or cooperation among multiple vehicles, while the low market penetration rate of autonomous vehicles may make system-specific benefits insignificant. Without proper planning and operation schemes, the advantages of automation technology can be cancelled out by its disadvantages. Given that the advantages of individual autonomous vehicles have been extensively explored, it is necessary to estimate the efficiency of transport systems involving autonomous vehicles. This thesis intends to solve the operation problem of autonomous vehicles in freight and public transport systems, focusing on system cost analysis.

    In freight transport, semi-autonomous truck platooning is a promising way to reduce fuel consumption. By instructing vehicles to form groups and drive together closely, the trailing vehicles experience reduced air resistance from the leading vehicle, and thus less fuel consumption. However, in practice, freight transport companies should also take time windows and transport reliability into consideration. The study answers the questions whether platoons should be formed and how significant can the savings be, considering driving cost, predefined time windows, travel time uncertainty and fuel cost. System optimization techniques, including stochastic optimization and mixed-integer linear programming, are adopted to minimize the total cost.

    In public transport, autonomous buses are assumed to save on-board crew cost, partially or fully. Similar with truck platoons, semi-autonomous buses can also form bus platoons for the purpose of eliminating the drivers from trailing buses. By contrast, fully autonomous buses are completely driverless and operates individually like conventional buses. To investigate the efficiency of autonomous buses, we compare the total cost of autonomous buses with conventional buses, where both passengers’ cost and service provider’s cost are modelled. In a general trunk-and-branches network connecting city center and suburbs, both fully autonomous bus and semi-autonomous bus systems are assessed. On a simple highly demanded corridor where demand varies during peak and off-peak hours, semi-autonomous bus platoons can be used as trains by extending its capacity in peak hours. Application of semi-autonomous vehicles are considered in traditional bus transit and BRT, by comparing with its conventional opponents.

  • 16.
    Zhang, Wei
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Badia, Hugo
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Efficiency of connected semi-autonomous platooning bus services in high-demand transit corridorsManuscript (preprint) (Other academic)
    Abstract [en]

    The paper investigates the efficiency of serving high demand transit corridors with connected semi-autonomous busplatoons in both bus and BRT services. Platooning could make it possible to provide higher capacity than with conventionalbuses by forming virtual long buses out of multiple smaller vehicles, which could be particularly relevant inscenarios with large variation in demand between peak and off-peak hours. The problem is formulated as a constrainedoptimization problem to minimize total system cost, which includes waiting cost, access cost, riding cost, operatingcost and capital cost. For single period with fixed demand, both analytical solutions and numerical examples areprovided. Sensitivity analysis is carried out with regard to demand levels and capacity upper bound. The problemis generalized to a two-period problem considering peak and off-peak demand. Numerical results are provided withsensitivity analysis regarding average demand level and ratio of peak/off-peak demand. Furthermore, the impact of alower bound on service headway is investigated. The result shows that semi-autonomous vehicle platooning is competitivein medium and high demand scenarios, with the potential of reduced users’ cost and operator’s operating costat the expense of additional rolling stock cost. The minimum headway, restricted vehicle size, and higher demandratio all make semi-autonomous platooning more advantageous.

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