Integrating automated vehicles into macroscopic travel demand models

Friedrich, Markus; Sonnleitner, Jörg; Richter, Emely

doi:10.1016/j.trpro.2019.09.060

Cited by 11 publications

(8 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this study a constant value is assumed for the capacity in the VDF of the macroscopic models, and the volume (demand) is adapted using the estimated PCU factors for AVs. This is one of the approaches adopted also in Friedrich et al ( 4 ). Therefore, to incorporate the impact of heterogeneous traffic with different vehicle types, such as AV, a PCU equivalent can be multiplied with the traffic volume.…”

Section: Methodsmentioning

confidence: 99%

“…A recent study ( 4 ) proposed a modeling framework for the integration of AV impacts, focusing on network capacity, into existing macroscopic travel demand models. The methodology involves extensive combinatorial analysis on disaggregated network elements (i.e., type of road, intersection) as well as different demand and supply interactions to quantify capacities in passenger car units (PCUs).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Autonomous Vehicles in Urban Networks: A Simulation-Based Assessment

Tympakianaki¹,

Nogués²,

Casas³

et al. 2022

Transportation Research Record: Journal of the Transportation R

View full text Add to dashboard Cite

The paper proposes a general framework for the assessment of the impacts of the introduction of Connected and Automated Transport Systems (CATS) on traffic. The main objective is to address the question of scalability and transferability of the identified impacts of Autonomous Vehicles (AVs) in particular, focusing on network performance of urban areas. A combination of microscopic and macroscopic simulations as well as statistical methods are applied. Microscopic simulation is conducted to measure the changes in network capacities by utilizing the concept of the Macroscopic Fundamental Diagram (MFD), under different AV penetration rates. The resulting capacities are used to estimate the effects on the Passenger Car Units (PCU) under different AV penetration rates and derive functional relationships, which are further introduced to travel demand models to forecast the macroscopic impacts on network performance. The results indicate a positive impact in relation to capacity changes resulting from the presence of AVs which vary with penetration rate. Analysis of three different urban networks, Barcelona, Bilbao (Spain), and Athens (Greece), reveals consistent trends. However, notable differences are observed on the estimated PCUs for Athens, potentially because of the different mixed-traffic composition. Further exploration of the critical AV modeling specifications and network characteristics is therefore required for deriving transferable PCU functional relationships across networks. Nevertheless, the static assignment results verify the expected trends in network performance impacts in relation to the applied PCU relationships. Finally, the transferability of the proposed methodology across networks is demonstrated.

show abstract

Section: Methodsmentioning

confidence: 99%

mentioning

confidence: 99%

Autonomous Vehicles in Urban Networks: A Simulation-Based Assessment

Tympakianaki¹,

Nogués²,

Casas³

et al. 2022

Transportation Research Record: Journal of the Transportation R

View full text Add to dashboard Cite

show abstract

“…e concept of passenger car units (PCUs) is used to represent the connection between volume and capacity, where capacity and vehicle volumes are converted into passenger car equivalents. Presuming that AVs differ from CVs in terms of performance and that this performance is also affected by the type of road environment, the PCU concept must be extended to AVs as well as intersections and roadway types [25][26][27][28].…”

Section: Literature Reviewmentioning

confidence: 99%

Macroscopic Experiments on Coexistence of Autonomous Vehicle Behavior on Various Heterogeneous Traffic Conditions

Desta

Tóth

2022

Journal of Advanced Transportation

View full text Add to dashboard Cite

Automated vehicles (AVs) are likely to bring paradigm shift in the future of transportation and in the transformation of urban space as they could reduce traffic accidents, energy consumption, and pollution while also lowering congestion expenses. To provide meaningful insights, there is a substantial need for investigation into the macroscopic evaluation of various evolutions of AVs using several measures of effectiveness. The main focus of this study is to evaluate the macroscopic operational impacts of AVs in terms of their driving logics, automation levels, and roadway type, all of which are adopted based on their passenger car unit (PCU) factors at various penetration rates, in order to assess the coexistence of AVs with heterogeneous traffic. The daily vehicle hours travelled, daily vehicle kilometers travelled, sum of delays on links, speed variation, and sum of vehicle volumes on links are used as measures of effectiveness parameters based on outputs of PTV Visum scenario manager. The results of the various scenario combinations depicted an overall improvement with advancement of driving logics, automation levels, and roadway types for each studied parameter. For instance, for better roadway condition with the motorway scenario and at higher AV penetration, the cautious driving behavior negatively affects the network performance, whereas favorable improvements are observed for the parameters of the normal and aggressive driving behaviors. Decision makers could make use of the insights obtained from the results to further shape the AV deployment aspects and extend the study considering infrastructure AV-readiness along with AV communication systems.

show abstract

“…These effects, which depend on the characteristics and the share of the AV, must be replicated in assignment and traffic flow models. Examples for such extensions can be found for assignment models in Friedrich et al (2019), for macroscopic traffic flow models in Friedrich (2016) and microscopic traffic flow models in Wagner (2016) and Sukennik et al (2018a).…”

Section: Capacity Impactsmentioning

confidence: 99%

Impacts of highly automated vehicles on travel demand: macroscopic modeling methods and some results

Sonnleitner¹,

Friedrich²,

Richter³

2021

Transportation

Self Cite

View full text Add to dashboard Cite

Automated vehicles (AV) will change transport supply and influence travel demand. To evaluate those changes, existing travel demand models need to be extended. This paper presents ways of integrating characteristics of AV into traditional macroscopic travel demand models based on the four-step algorithm. It discusses two model extensions. The first extension allows incorporating impacts of AV on traffic flow performance by assigning specific passenger car unit factors that depend on roadway type and the capabilities of the vehicles. The second extension enables travel demand models to calculate demand changes caused by a different perception of travel time as the active driving time is reduced. The presented methods are applied to a use case of a regional macroscopic travel demand model. The basic assumption is that AV are considered highly but not fully automated and still require a driver for parts of the trip. Model results indicate that first-generation AV, probably being rather cautious, may decrease traffic performance. Further developed AV will improve performance on some parts of the network. Together with a reduction in active driving time, cars will become even more attractive, resulting in a modal shift towards car. Both circumstances lead to an increase in time spent and distance traveled.

show abstract

Integrating automated vehicles into macroscopic travel demand models

Cited by 11 publications

References 10 publications

Autonomous Vehicles in Urban Networks: A Simulation-Based Assessment

Autonomous Vehicles in Urban Networks: A Simulation-Based Assessment

Macroscopic Experiments on Coexistence of Autonomous Vehicle Behavior on Various Heterogeneous Traffic Conditions

Impacts of highly automated vehicles on travel demand: macroscopic modeling methods and some results

Contact Info

Product

Resources

About