,
Rong Gu
,
Cristina Seceleanu
,
Ning Xiong
,
Peter Backeman
,
Tiberiu Seceleanu
,
Zhennan Fei
,
Ali Nouri
Creative Commons Attribution 4.0 International license
The validation of Automated Driving Systems (ADSs) has shifted from distance-based metrics to Scenario-Based Testing (SBT). Large Language Models (LLMs) have emerged as powerful tools with potential for generating vehicular scenarios at scale. However, generative models, used for direct simulation synthesis, produce inadequate output, therefore necessitating a more structured compilation approach. In this regard, we present HASCO (Hybrid AI Simulation COmpiler), a system that translates natural-language driving scene specifications into executable simulation artifacts (XOSC/XODR files) for the esmini/OpenSCENARIO ecosystem. While LLMs excel at narrative parsing, we demonstrate that direct synthesis of simulation artifacts fails in the vast majority of cases due to hallucinated physics or schema violations. To resolve this, HASCO treats scenario creation as a compilation task rather than a generative one. The pipeline supports three compilation paths: direct synthesis, a Python intermediate (via scenariogeneration), and an ontology-guided path that grounds intent into an intermediate representation (IR) before compilation. We further evaluate a self-judging mechanism for automated repair. Across six operating modes evaluated on 40 real-world accident reports, the ontology-guided compiler and Python-based compiler achieve 95% and 90% executability rates, respectively (compared to 5% for direct synthesis). Additionally, we evaluate outputs on semantic fidelity, positioning HASCO as a robust tool for forensic scene reconstruction.
@InProceedings{jelacic_et_al:OASIcs.AEiC.2026.4,
author = {Jela\v{c}i\'{c}, Edin and Gu, Rong and Seceleanu, Cristina and Xiong, Ning and Backeman, Peter and Seceleanu, Tiberiu and Fei, Zhennan and Nouri, Ali},
title = {{HASCO: A Hybrid AI Simulation Compiler for Semantic Accident Reconstruction}},
booktitle = {30th Ada-Europe International Conference on Reliable Software Technologies (AEiC 2026)},
pages = {4:1--4:22},
series = {Open Access Series in Informatics (OASIcs)},
ISBN = {978-3-95977-425-3},
ISSN = {2190-6807},
year = {2026},
volume = {143},
editor = {Filieri, Antonio and Backeman, Peter},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.AEiC.2026.4},
URN = {urn:nbn:de:0030-drops-259220},
doi = {10.4230/OASIcs.AEiC.2026.4},
annote = {Keywords: Autonomous Driving, OpenSCENARIO, Large Language Models, Scenario Generation, Semantic Reconstruction}
}