Traffic-R1: Reinforced LLMs Bring Human-Like Reasoning to Traffic Signal Control Systems
On the map: LLM reasoning → Chain-of-thought reasoning for driving
Abstract (arXiv)
We introduce Traffic-R1, a 3B-parameter foundation model with human-like reasoning for Traffic signal control (TSC), developed via self-exploration and iterative reinforcement of LLM with expert guidance in a simulated traffic environment. Compared with traditional reinforcement learning and recent LLM-based methods, Traffic-R1 offers three main advantages: zero-shot generalization, transferring unchanged to new road networks and out-of-distribution incidents by leveraging internal traffic-control policies and reasoning; a compact 3B-parameter design that supports real-time inference on mobile-class chips for edge deployment; and an explainable TSC process that enables multi-intersection coordination through communication and an asynchronous communication network. Extensive benchmarks show Traffic-R1 outperforms strong baselines and training-intensive RL controllers. In production, the model now manages signals affecting over 55,000 drivers daily, reduces average queue lengths by more than 5%, and halves operator workload. Our model is available at https://huggingface.co/Season998/Traffic-R1.
Key facts. Cited by 12 papers in the map (data through 14 Oct 2026). Placed in Chain-of-thought reasoning for driving, one of 17 directions in LLM reasoning. Builds on 19 of its 58 references that are in the map. First posted on arXiv 4 Aug 2025.
Builds on
19 of 58 references.
Closest ancestors · 1
Same direction, newest first
Other references · 18
- 2022Training a Helpful and Harmless Assistant with Reinforcement Learning from Human Feedbackcited by 3,720
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- 2024HybridFlow: A Flexible and Efficient RLHF Frameworkcited by 2,057
- 2024DeepSeek-V3 Technical Reportcited by 811
- 2024Large Language Models: A Surveycited by 525
- 2025RAGEN: Understanding Self-Evolution in LLM Agents via Multi-Turn Reinforcement Learningcited by 386
- 2025Towards Large Reasoning Models: A Survey of Reinforced Reasoning with Large Language Modelscited by 293
- 2022Is Reinforcement Learning (Not) for Natural Language Processing: Benchmarks, Baselines, and Building Blocks for Natural Language Policy Optimizationcited by 246
- 2023DiLu: A Knowledge-Driven Approach to Autonomous Driving with Large Language Modelscited by 207
- 2023Vision Language Models in Autonomous Driving: A Survey and Outlookcited by 126
- 2025A Survey of Frontiers in LLM Reasoning: Inference Scaling, Learning to Reason, and Agentic Systemscited by 111
- 2024Faithfulness vs. Plausibility: On the (Un)Reliability of Explanations from Large Language Modelscited by 105
6 more
- 2023LLMLight: Large Language Models as Traffic Signal Control Agentscited by 73
- 2024LLM-Assisted Light: Leveraging Large Language Model Capabilities for Human-Mimetic Traffic Signal Control in Complex Urban Environmentscited by 31
- 2021Efficient Pressure: Improving efficiency for signalized intersectionscited by 24
- 2025CoLLMLight: Cooperative Large Language Model Agents for Network-Wide Traffic Signal Controlcited by 15
- 2022The Real Deal: A Review of Challenges and Opportunities in Moving Reinforcement Learning-Based Traffic Signal Control Systems Towards Realitycited by 9
- 2024TSCLIP: Robust CLIP Fine-Tuning for Worldwide Cross-Regional Traffic Sign Recognitioncited by 4
Built on by
Citing papers per year: 2025: 2; 2026: 10.
12 papers.
- 2026TimeOmni-VL: Unified Models for Time Series Understanding and Generationcited by 7
- 2025Urban-R1: Reinforced MLLMs Mitigate Geospatial Biases for Urban General Intelligencecited by 3
- 2026ReRec: Reasoning-Augmented LLM-based Recommendation Assistant via Reinforcement Fine-tuningcited by 3
- 2025A Dual Large Language Models Architecture with Herald Guided Prompts for Parallel Fine Grained Traffic Signal Controlcited by 2
- 2026SignalClaw: LLM-Guided Evolutionary Synthesis of Interpretable Traffic Signal Control Skillscited by 1
- 2026LLM Agents for Time-Series: A Surveycited by 1
- 2026CuraLight: Debate-Guided Data Curation for LLM-Centered Traffic Signal Controlcited by 0
- 2026DGLight: DQN-Guided GRPO Fine-Tuning of Large Language Models for Traffic Signal Controlcited by 0
- 2026ReasonLight: A Multimodal Foundation Model-Enhanced Reinforcement Learning Framework for Zero-Shot Traffic Signal Controlcited by 0
- 2026LLM-Based Hierarchical Coordinated Control with Continuation-Aware Policy Learningcited by 0
- 2026ProcessLight: Process Supervision for Large Language Model Based Traffic Signal Controlcited by 0
- 2026VLALight: A Vision-Language-Action Model for Traffic Signal Controlcited by 0
- 2026VLALight: A Vision-Language-Action Model for Traffic Signal Control29 Sep 2026
- 2026ProcessLight: Process Supervision for Large Language Model Based Traffic Signal Control19 Sep 2026
- 2026LLM Agents for Time-Series: A Survey26 Aug 2026
- 2026LLM-Based Hierarchical Coordinated Control with Continuation-Aware Policy Learning15 Aug 2026
- 2026ReasonLight: A Multimodal Foundation Model-Enhanced Reinforcement Learning Framework for Zero-Shot Traffic Signal Control28 May 2026
- 2026DGLight: DQN-Guided GRPO Fine-Tuning of Large Language Models for Traffic Signal Control28 Apr 2026
- 2026ReRec: Reasoning-Augmented LLM-based Recommendation Assistant via Reinforcement Fine-tuning9 Apr 2026
- 2026CuraLight: Debate-Guided Data Curation for LLM-Centered Traffic Signal Control7 Apr 2026
- 2026SignalClaw: LLM-Guided Evolutionary Synthesis of Interpretable Traffic Signal Control Skills7 Apr 2026
- 2026TimeOmni-VL: Unified Models for Time Series Understanding and Generation19 Feb 2026
- 2025A Dual Large Language Models Architecture with Herald Guided Prompts for Parallel Fine Grained Traffic Signal Control31 Oct 2025
- 2025Urban-R1: Reinforced MLLMs Mitigate Geospatial Biases for Urban General Intelligence18 Oct 2025
Similar, not cited
Close in wording, no citation either way
- 2023A Fully Data-Driven Approach for Realistic Traffic Signal Control Using Offline Reinforcement Learning
- 2026LATS: Large Language Model Assisted Teacher-Student Framework for Multi-Agent Reinforcement Learning in Traffic Signal Control
- 2025Robustness of Reinforcement Learning-Based Traffic Signal Control under Incidents: A Comparative Study
- 2026EvoSignal: LLM-Guided Evolutionary Design of Modular Traffic Signal Control Programs
- 2025Evolutionary Discovery of Heuristic Policies for Traffic Signal Control
- 2026Explainable Reinforcement Learning for Adaptive Traffic Signal Control
- 2023Traffic Signal Control Using Lightweight Transformers: An Offline-to-Online RL Approach
- 2024iLLM-TSC: Integration reinforcement learning and large language model for traffic signal control policy improvement