LangTraj is a novel diffusion model that enables intuitive, language-based control of traffic simulations for more efficient and safer autonomous vehicle testing.

• Creates realistic multi-agent scenarios through natural language instructions
• Enables counterfactual testing of autonomous vehicles in challenging conditions
• Generates nuanced interactions between vehicles for comprehensive safety evaluation
• Provides more intuitive control than traditional parameter-based simulation methods

Security Impact: This approach significantly enhances AV safety validation by allowing testers to easily generate diverse safety-critical scenarios using simple language prompts rather than complex mathematical parameters.

LANGTRAJ: Diffusion Model and Dataset for Language-Conditioned Trajectory Simulation