mixed-autonomy traffic control

Scaling Up Reinforcement Learning for Traffic Smoothing: A 100-AV Highway Deployment

Berkeley AI Research (BAIR) deployed 100 RL-controlled autonomous vehicles into real rush-hour highway traffic on Interstate 24 near Nashville to dampen stop-and-go waves and reduce fuel consumption. The RL controllers were trained in data-driven simulations built from real highway trajectory data, using only local sensor inputs (speed, lead vehicle speed, gap) to enable decentralized deployment on standard vehicles. Reward design balanced wave smoothing, energy efficiency, safety, comfort, and adherence to human driving norms. The paper documents the sim-to-real transfer challenges encountered during this large-scale field experiment.