Travel Behavior

Collaborative High-Accuracy Localization in Mobile Multipath Environments

Ekambaram, Venkatesan N.
Ramchandran, Kannan
Raja Sengupta
2016

We study the problem of high-accuracy localization of mobile nodes in a multipath-rich environment where submeter accuracy values are required. We employ a peer-to-peer framework where nodes can get pairwise multipath-degraded ranging estimates in local neighborhoods, with the multipath noise correlated across time. The challenge is to enable high-accuracy positioning under severe multipath conditions when the fraction of received signals corrupted by multiple paths is significant. Our contributions are twofold. We provide a practical distributed localization algorithm by invoking an...

Drones in Smart Cities: Overcoming Barriers Through Air Traffic Control Research

Foina, Aislan Gomide
Raja Sengupta
Lerchi, Patrick
Liu, Zhilong
Krainer, Clemens
2015

Within the last decade, the recent automation of vehicles such as cars and planes promise to fundamentally alter the microeconomics of transporting people and goods. In this paper, we focus on the self-flying planes (drones), which have been renamed Unmanned Aerial System (UAS) by the US Federal Aviation Agency (FAA). The most controversial operations envisaged by the UAS industry are small, low-altitude UAS flights in densely populated cities - robotic aircraft flying in the midst of public spaces to deliver goods and information. This subset of robotic flight would be the most valuable...

Cooperative and Non-Cooperative UAS Traffic Volumes

Bulusu, Vishwanath
Raja Sengupta
Polishchuk, Valentin
Sedov, Leonid
2017

We describe an analytical process to determine how much UAS traffic is feasible. The process is a simulator and data processing tools. The two are applied to the US San Francisco Bay Area and Norrkoping, Sweden. The amount of UAS traffic is measured in flights per day and simulated up to 200,000 flights. A UAS traffic volume is feasible if specified metrics meet operational requirements with high probability and are stable, in the sense of being below thresholds observed for monotone properties in random geometric graphs. We focus on conflict cluster size and argue for it as a fundamental...

The San Francisco Travel Quality Study: Tracking Trials and Tribulations of a Transit Taker

Carrel, Andre
Raja Sengupta
Walker, Joan L.
2017

In helping understand the dynamics of travel choice behavior and traveler satisfaction over time, multi-day panel data is invaluable (McFadden in Am Econ Rev 91(3): 351–378, 2001). The collection of such data has become increasingly feasible thanks to smartphones, which researchers can use to present surveys to travelers and to collect additional information through the phones’ location services and other sensors. This paper describes the design and implementation of the San Francisco Travel Quality Study, a multi-day research study conducted in autumn 2013 with 838 participants. The...

The San Francisco Travel Quality Study: tracking trials and tribulations of a transit taker

Carrel, Andre
Raja Sengupta
Joan Walker
2017

In helping understand the dynamics of travel choice behavior and traveler satisfaction over time, multi-day panel data is invaluable (McFadden in Am Econ Rev 91(3): 351–378, 2001). The collection of such data has become increasingly feasible thanks to smartphones, which researchers can use to present surveys to travelers and to collect additional information through the phones’ location services and other sensors. This paper describes the design and implementation of the San Francisco Travel Quality Study, a multi-day research study conducted in autumn 2013 with 838 participants. The...

Chapter 31 - Innovative Pricing Policies for Commuting: A Field Experiment

Lehner, Stephan
Peer, Stefanie
Gren, Mateusz
Koller, Hannes
Dragaschnig, Melitta
Brändle, Norbert
Raja Sengupta
2020

Based on an innovative field experiment, this paper analyzes the effect of spatially and temporally differentiated pricing instruments on the travel behavior of commuters. The study aims to understand the underlying preferences, trade-offs, and restrictions faced by participants. The experiment uses a smartphone-based tracking technology performing automatic detection of travel modes. We recruited volunteers commuting by car to Vienna (Austria). A dedicated app recorded the commuting behavior of 95 participants throughout five weeks, including a week of pre- and post-measurement,...

Urban Air Mobility: Viability of Hub-Door and Door-Door Movement by Air

Bulusu, Vishwanath
Raja Sengupta
2020

Owing to a century of innovation in connected and automated aircraft design, for the rst time in history, air transport presents a potential competitive alternative to road, for hub-to-door and door-to-door urban services. In this article, we study the viability of air transport, for moving people and goods in an urban area, based on three metrics - enroute travel time, fuel cost and carbon dioxide (CO2) emissions. We estimate the metrics from emission standards and operational assumptions on vehicles based on current market data and compare electric air travel to gasoline road travel. For...

Research Brief: The Changing Impacts of the COVID-19 Pandemic on Individuals and Households in the U.S.

Bouzaghrane, Mahamed Amine
Obeid, Hassan
Parker, Madeleine
Hayes, Drake
Chen, Minnie
Karen Trapenberg Frick
Daniel Rodriguez
Joan Walker
Raja Sengupta
Daniel Chatman
2021

This brief describes findings from a research effort to understand the changing impacts of the pandemic upon households from different places and backgrounds living in the United States. We investigated the effects of the pandemic along with pandemic-based restrictions and rules on people’s behavior along with their mental and emotional health, social relations, and livelihoods. Unlike other research efforts, as far as we are aware this effort is the only one to join passive data from cell phones with survey information collected from the same individuals over time. We combined these data...

Hierarchical Vertiport Network Design for On-Demand Multi-modal Urban Air Mobility

Peng, Xin
Bulusu, Vishwanath
Raja Sengupta
2022

The vertiports that connect ground and air transportation modes play a critical role in enabling Urban Air Mobility (UAM). Parameters like aircraft occupancy and vertiport operational capacity, along with the ground traffic congestion near vertiports have dominant impacts on the vertiport network design and consequently on the total addressable market and value proposition of UAM. We propose a hierarchical method to design a vertiport network for multi-modal UAM with multiple-seat aircraft based on the passenger demand. Our objective is to determine vertiport locations and assign...

Public Transit Use in the United States in the Era of COVID-19: Transit Riders’ Travel Behavior in the COVID-19 Impact and Recovery Period

Parker, Madeleine E. G.
Li, Meiqing
Bouzaghrane, Mohamed Amine
Obeid, Hassan
Hayes, Drake
Karen Trapenberg Frick
Daniel Rodriguez
Raja Sengupta
Joan Walker
Daniel Chatman
2021

COVID-19 has upended travel across the world, disrupting commute patterns, mode choices, and public transit systems. In the United States, changes to transit service and reductions in passenger volume due to COVID-19 are lasting longer than originally anticipated. In this paper we examine the impacts of the COVID-19 pandemic on individual travel behavior across the United States. We analyze mobility data from Janurary to December 2020 from a sample drawn from a nationwide smartphone-based panel curated by a private firm, Embee Mobile. We combine this with a survey that we administered to...