Data

Deploying Traffic Smoothing Cruise Controllers Learned from Trajectory Data

Lichtle, Nathan
Vinitsky, Eugene
Nice, Matthew
Seibold, Benjamin
Work, Dan
Bayen, Alexandre M.
2022

Autonomous vehicle-based traffic smoothing con-trollers are often not transferred to real-world use due to challenges in calibrating many-agent traffic simulators. We show a pipeline to sidestep such calibration issues by collecting trajectory data and learning controllers directly from trajectory data that are then deployed zero-shot onto the highway. We construct a dataset of 772.3 kilometers of recorded drives on the I–24. We then construct a simple simulator using the recorded drives as the lead vehicle in front of a simulated platoon consisting of one autonomous vehicle and five human...

Traffic Smoothing Controllers for Autonomous Vehicles Using Deep Reinforcement Learning and Real-World Trajectory Data

Lichtle, Nathan
Jang, Kathy
Shah, Adit
Vinitsky, Eugene
Lee, Jonathan W.
Bayen, Alexandre M.
2023

Designing traffic-smoothing cruise controllers that can be deployed onto autonomous vehicles is a key step towards improving traffic flow, reducing congestion, and enhancing fuel efficiency in mixed autonomy traffic. We bypass the common issue of having to carefully fine-tune a large traffic micro-simulator by leveraging real-world trajectory data from the I–24 highway in Tennessee, replayed in a one-lane simulation. Using standard deep reinforcement learning methods, we train energy-reducing wave-smoothing policies. As an input to the agent, we observe the speed and distance of only the...

Integrating Multi-Source Data for Bi-Level Traffic Simulator Calibration: A Literature Review and Highway Case Study

Samaei, Maryam
Ameli, Mostafa
Davis, Jon F.
McQuade, Sean T.
Lee, Jonathan W.
Piccoli, Benedetto
Bayen, Alexandre M.
2024

Traffic simulation serves as a powerful tool for pre-evaluating policies and technologies. In this context, simulation-based Dynamic traffic assignment (DTA) models are capable of capturing traffic dynamics. They are well-known as critical tools in controlling and predicting traffic situations. The reliability of simulation results heavily depends on the calibration process. Most studies in the literature formulate and calibrate simulators based on a single source of collected data or multiple data sets with the same spatiotemporal characteristics. However, in practice, traffic data is...

Validation and Calibration of Energy Models with Real Vehicle Data from Chassis Dynamometer Experiments

Carpio, Joy
Almatrudi, Sulaiman
Khoudari, Nour
Fu, Zhe
Butts, Kenneth
Lee, Jonathan
Seibold, Benjamin
Bayen, Alexandre
2025

Accurate estimation of vehicle fuel consumption typically requires detailed modeling of complex internal powertrain dynamics, often resulting in computationally intensive simulations. However, many transportation applications-such as traffic flow modeling, optimization, and control-require simplified models that are fast, interpretable, and easy to implement, while still maintaining fidelity to physical energy behavior. This work builds upon a recently developed model reduction pipeline that derives physics-like energy models from high-fidelity Autonomie vehicle simulations. These reduced...

Application of Fuzzy Logic and Neural Networks to Automatically Detect Freeway Traffic Incidents

Hsiao, Chien-Hua
Lin, Ching-Teng
Cassidy, Michael
1994

To date, efforts to manage freeway congestion have been seriously impeded by the inability to promptly and reliably detect the presence of traffic incidents. Traditional incident‐detection algorithms distinguish between congested and uncongested operation by comparing measured traffic‐stream parameters with predefined threshold values. Given the range of possible operating conditions in the traffic stream, selecting a single threshold value, and the suitability of that selected threshold, is full of uncertainty. This inherent uncertainty makes fuzzy logic a promising approach to...

Middleware for Cooperative Vehicle-Infrastructure Systems

Manasseh, Christian
Sengupta, Raja
2008

Middleware has emerged as an important architectural component in supporting distributed applications. The role of middleware is to present a unified programming model to application writers and to mask out problems of heterogeneity and distribution. Mobile sensors fall into the space of distributed systems that suffer from isolated data sources, heterogeneous communication infrastructure and varying application requirements. In this report, we provide a middleware architecture that addresses the needs of a distributed system made of mobile sensors in general and discuss the implementation...

Modeling The Santa Monica Freeway Corridor: A Feasibility Study

Skabardonis, Alexander
Dahlgren, Joy
May, Adolf D.
1998

This report presents the findings of a feasibility study which developed a simulation testbed for the Santa Monica freeway corridor. The study involved performing an evaluation of the state-of-the-art models for Advanced Traffic Management and Traffic Information Systems (ATMIS) on freeway corridors. The evaluation was based on the model capabilities, input data requirements and output options, with focus on the record of real-life calibration, validation and practical application of the models. The findings show that the CORSIM and INTEGRATION models have the higher probability of...

Traffic Data Measurement and Validation

Coifman, Benjamin
2001

Caltrans collects traffic data for many monitoring and control applications and the ultimate goal of the traffic surveillance system is to provide accurate data to these high level applications. The surveillance system includes data measurement, averaging and verification algorithms. This report presents improvements to many elements of the surveillance system. First, section 2addresses many shortcomings in average speed estimation at single loop detectors, as well as other sensors that estimate speed from average flow and occupancy. At the root of these problems is the fact that the...

Assessing the Benefits and Costs of ITS Projects: Volume 1 Methodology

Gillen, David
Li, Jianling
Dahlgren, Joy
Chang, Elva
1999

In this document a framework for evaluating ITS projects is developed. One of the central issues addressed is whether ITS projects are distinctly different from other more conventional transportation projects and thus the traditional decision methods such as Benefit-cost analysis cannot be used. The answer is mixed. The decision models used in the past are still relevant, however, these have been applied in an environment in which there was a well developed data base. The models identified, selected, assembled and evaluated data to make judgements as to whether the proposed projects were...

Health of California’s Loop Detector System

Rajagopal, Ram
Varaiya, Pravin
2007

The California Department of Transportation (Caltrans) freeway sensor network has two components: the sensor system of 25,000 inductive loop sensors grouped into 8,000 vehicle detector stations (VDS) and covering 30,500 freeway direction-miles; and the communication network over which the sensor measurements are transported to Caltrans Traffic Management Centers. The sensor network is virtually the only source of data for use in traffic operations, performance measurement, planning and traveler information. However, the value of these data is greatly reduced by the poor reliability of the...