ITS Berkeley

Traffic Control via Connected and Automated Vehicles (CAVs): An Open-Road Field Experiment with 100 CAVs

Lee, Jonathan W.
Wang, Han
Jang, Kathy
Lichtle, Nathan
Hayat, Amaury
Bunting, Matthew
Alanqary, Arwa
Barbour, William
Fu, Zhe
Gong, Xiaoqian
Gunter, George
Hornstein, Sharon
Kreidieh, Abdul Rahman
Nice, Mat-Thew W.
Richardson, William A.
Shah, Adit
Vinitsky, Eugene
Wu, Fangyu
Xiang, Shengquan
Almatrudi, Sulaiman
Althukair, Fahd
Bhadani, Rahul
Carpio, Joy
Chekroun, Raphael
Cheng, Eric
Chiri, Maria Teresa
Chou, Fang-Chieh
Delorenzo, Ryan
Gibson, Marsalis
Gloudemans, Derek A.
Gollakota, Anish
Ji, Junyi
Keimer, Alexander
Khoudari, Nour
Mahmood, Malaika
Mahmood, Mikail
Matin, Hossein Nick Zinat
McQuade, Sean T.
Ramadan, Rabie
Urieli, Daniel
Wang, Xia
Wang, Yanbing
Xu, Rita
Yao, Mengsha
You, Yiling
Zachár, Gergely
Zhao, Yibo
Ameli, Mostafa
Baig, Mirza Najamuddin
Bhaskaran, Sarah
Butts, Kenneth
Gowda, Manasi
Janssen, Caroline
Lee, John
Pedersen, Liam
Wagner, Riley
Zhang, Zimo
Zhou, Chang
Work, Daniel B.
Seibold, Benjamin
Sprinkle, Jonathan M.
Piccoli, Benedetto
Monache, Maria Laura Delle
Bayen, Alexandre M.
2025

The CIRCLES project aims to reduce instabilities in traffic flow, which are naturally occurring phenomena due to human driving behavior. Also called “phantom jams” or “stop-and-go waves,” these instabilities are a significant source of wasted energy. Toward this goal, the CIRCLES project designed a control system, referred to as the MegaController by the CIRCLES team, that could be deployed in real traffic. Our field experiment, the MegaVanderTest (MVT), leveraged a heterogeneous fleet of 100 longitudinally controlled vehicles as Lagrangian traffic actuators, each of which ran a controller...

Hierarchical Speed Planner for Automated Vehicles: A Framework for Lagrangian Variable Speed Limit in Mixed-Autonomy Traffic

Wang, Han
Fu, Zhe
Lee, Jonathan W.
Matin, Hossein Nick Zinat
Alanqary, Arwa
Urieli, Daniel
Hornstein, Sharon
Kreidieh, Abdul Rahman
Chekroun, Raphael
Barbour, William
Richardson, William A.
Work, Dan
Piccoli, Benedetto
Seibold, Benjamin
Sprinkle, Jonathan M.
Bayen, Alexandre M.
Monache, Maria Laura Delle
2025

This article presents a novel hierarchical speed planning framework for variable speed limits in mixed-autonomy traffic environments, leveraging server-side macroscopic control and vehicle-side microscopic execution. The framework integrates real-time traffic state estimation (TSE) and reinforcement learning (RL)-based control to mitigate congestion and improve traffic flow. A TSE enhancement module combines macroscopic data from sources like INRIX with high-resolution observations from connected autonomous vehicles (CAVs), enabling predictive modeling to address latency and noise. The...

Modeling, Monitoring, and Controlling Road Traffic Using Vehicles to Sense and Act

Monache, Maria Laura Delle
McQuade, Sean T.
Matin, Hossein Nick Zinat
Gloudemans, Derek A.
Wang, Yanbing
Gunter, George L.
Bayen, Alexandre M.
Lee, Jonathan W.
Piccoli, Benedetto
Seibold, Benjamin
Sprinkle, Jonathan M.
Work, Daniel B.
2025

This review offers a comprehensive overview of current traffic modeling, estimation, and control methods, along with resulting field experiments. It highlights key developments and future directions in leveraging technological advancements to improve traffic management and safety. The focus is on macroscopic, microscopic, and micro-macro models, as well as state-of-the-art control techniques and estimation methods for deploying vehicles in traffic field experiments.

Reevaluating Policy Gradient Methods for Imperfect-Information Games

Rudolph, Max
Lichtle, Nathan
Mohammadpour, Sobhan
Bayen, Alexandre
Kolter, J. Zico
Zhang, Amy
Farina, Gabriele
Vinitsky, Eugene
Sokota, Samuel
2025

In the past decade, motivated by the putative failure of naive self-play deep reinforcement learning (DRL) in adversarial imperfect-information games, researchers have developed numerous DRL algorithms based on fictitious play (FP), double oracle (DO), and counterfactual regret minimization (CFR). In light of recent results of the magnetic mirror descent algorithm, we hypothesize that simpler generic policy gradient methods like PPO are competitive with or superior to these FP, DO, and CFR-based DRL approaches. To facilitate the resolution of this hypothesis, we implement and release the...

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...

A Proposed Analytical Technique for the Design and Analysis of Major Freeway Weaving Sections

Cassidy, Michael James
1990

Weaving occurs when merging traffic streams entering a freeway from an on-ramp cross over diverging traffic streams exiting the freeway via a nearby off-ramp. The intense lane-changing activity which typically occurs in weaving areas can create significant operational problems. Thus, weaving sections often represent bottleneck locations in urban freeway systems. The prevalence of weaving areas on U.S. freeways warrants the need for analytical techniques which can reliably analyze and/or design these critical freeway components. However, previous research at the Institute of Transportation...