Saved in:
Bibliographic Details
Main Authors: Jaisankar, Kanishkha, Tandel, Sunidhi
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2510.10503
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915548700344320
author Jaisankar, Kanishkha
Tandel, Sunidhi
author_facet Jaisankar, Kanishkha
Tandel, Sunidhi
contents Motion planning in complex scenarios is a core challenge in autonomous driving. Conventional methods apply predefined rules or learn from driving data to generate trajectories, while recent approaches leverage large language models (LLMs) for decision-making. However, it remains unclear whether LLMs truly capture human driving logic. We propose Align2Act, a motion planning framework that transforms instruction-tuned LLMs into interpretable planners aligned with human behavior. We derive structured driving instructions based on human reasoning patterns (e.g., anticipate hazards, yield at intersections) and traffic rules (e.g., stop at red lights, maintain lane boundaries). Our Align2ActChain module guides step-by-step reasoning to produce both an interpretable rationale and a safe trajectory. By fine-tuning LLaMA-2-7B with LoRA on one million scenarios from the nuPlan dataset, our method achieves an open-loop score of 85.17 and closed-loop scores of 70.31 (non-reactive) and 66.96 (reactive) on Test14-random. Unlike prior work focused on synthetic or open-loop settings, we demonstrate improved planning quality and human-likeness on the real-world nuPlan closed-loop benchmark. Ablation studies confirm that structured reasoning significantly improves performance over baseline LLM planners.
format Preprint
id arxiv_https___arxiv_org_abs_2510_10503
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Align2Act: Instruction-Tuned Models for Human-Aligned Autonomous Driving
Jaisankar, Kanishkha
Tandel, Sunidhi
Machine Learning
Artificial Intelligence
Robotics
Motion planning in complex scenarios is a core challenge in autonomous driving. Conventional methods apply predefined rules or learn from driving data to generate trajectories, while recent approaches leverage large language models (LLMs) for decision-making. However, it remains unclear whether LLMs truly capture human driving logic. We propose Align2Act, a motion planning framework that transforms instruction-tuned LLMs into interpretable planners aligned with human behavior. We derive structured driving instructions based on human reasoning patterns (e.g., anticipate hazards, yield at intersections) and traffic rules (e.g., stop at red lights, maintain lane boundaries). Our Align2ActChain module guides step-by-step reasoning to produce both an interpretable rationale and a safe trajectory. By fine-tuning LLaMA-2-7B with LoRA on one million scenarios from the nuPlan dataset, our method achieves an open-loop score of 85.17 and closed-loop scores of 70.31 (non-reactive) and 66.96 (reactive) on Test14-random. Unlike prior work focused on synthetic or open-loop settings, we demonstrate improved planning quality and human-likeness on the real-world nuPlan closed-loop benchmark. Ablation studies confirm that structured reasoning significantly improves performance over baseline LLM planners.
title Align2Act: Instruction-Tuned Models for Human-Aligned Autonomous Driving
topic Machine Learning
Artificial Intelligence
Robotics
url https://arxiv.org/abs/2510.10503