Safety validation for connected autonomous vehicles using large-scale testing tracks in high-fidelity simulation environment
Open accessAbstract
• Proposed a co-simulation framework for systematic safety evaluations of CAVs in large-scale networks. • Observed that safety benefits do not consistently correlate linearly with increasing CAV penetration rates. • Identified optimal stability between automated and human-driven vehicles at 70% CAV penetration. • Found that roundabouts and signalized intersections account for over 70% of conflicts involving CAVs. Public concern over the implementation of Connect Autonomous Vehicles (CAVs) remains a significant issue, and safety validation for CAVs remains a critical challenge due to the limitations of existing testing methods. While real-world testing is crucial, it can be expensive, time-consuming, and potentially impractical for evaluating the operation of CAV fleets. This paper presents a comprehensive co-simulation framework integrating the fully compiled CARLA with traffic microsimulation to establish a large-scale (20 × 20 km 2 ) testing environment for systematic CAV safety validation. The framework encompasses three key components: 1) a high-fidelity testing environment featuring diverse road geometries and dynamic conditions including weather variations and realistic traffic flows; 2) an intelligent CAV function developed through deep reinforcement learning and enhanced with utility-based connectivity strategies; 3) A sophisticated safety measurement metric that utilizes surrogate safety assessments, integrating a multi-type Bayesian hierarchical model to comprehensively evaluate risk factors and incident probabilities. The case study assessed CAV penetration rates ranging from 0 % to 100 %, identifying an optimal safety performance at a 70 % penetration rate, which resulted in an 86.05 % reduction in accident rates compared to conventional driving scenarios. This optimal safety level was effectively achieved in rural and suburban areas, where the average conflict probability was 0.4. However, in transition zones that connect high-, medium-, and low-density areas, significant traffic conflicts persisted even at this optimal penetration rate, with a conflict probability exceeding 0.7. Key results highlight critical safety patterns under optimal conditions, revealing that roundabouts and signalized intersections account for over 70 % of conflicts involving CAVs. This work advances CAV safety validation by providing a more realistic, large-scale testing environment that compensates for real-world testing limitations and allows for comprehensive safety evaluations across diverse scenarios.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
Cites
Human-level control through deep reinforcement learning
Mnih, V., Kavukcuoglu, K., Silver, D., Rusu, A. A., Veness, J., Bellemare, M. G., Graves, A., Riedmiller, M., Fidjeland, A. K., Ostrovski, G., et al. (2015) · Nature · doi:10.1038/nature14236 · Cited by 30,357 · see citing works
CARLA: An open urban driving simulator
Dosovitskiy, A., Ros, G., Codevilla, F., Lopez, A., & Koltun, V. (2017) · arXiv · doi:10.48550/arxiv.1711.03938 · Cited by 3,718 · see citing works
Challenges in autonomous vehicle testing and validation
Koopman, P., & Wagner, M. (2016) · SAE International Journal of Transportation Safety · doi:10.4271/2016-01-0128 · Cited by 675 · see citing works
Statistics of Extremes: Theory and Applications
Lazar, N. A. (2005) · Technometrics · doi:10.1198/tech.2005.s297 · Cited by 517 · see citing works
Evaluating the safety impact of connected and autonomous vehicles on motorways
Papadoulis, A., Quddus, M., & Imprialou, M. (2019) · Accident Analysis & Prevention · doi:10.1016/j.aap.2018.12.019 · Cited by 480 · see citing works
Feng, S., Yan, X., Sun, H., Feng, Y., & Liu, H. X. (2021) · Nature Communications · doi:10.1038/s41467-021-21007-8 · Cited by 413 · see citing works
Li, G., Yang, Y., Li, S., Qu, X., Lyu, N., & Li, S. E. (2022) · Transportation Research Part C: Emerging Technologies · doi:10.1016/j.trc.2021.103452 · Cited by 308 · see citing works
Virdi, N., Grzybowska, H., Waller, S. T., & Dixit, V. V. (2019) · Accident Analysis & Prevention · doi:10.1016/j.aap.2019.06.001 · Cited by 211 · see citing works
Experimental validation of connected automated vehicle design among human-driven vehicles
Ge, J. I., Avedisov, S. S., He, C. R., Qin, W. B., Sadeghpour, M., & Orosz, G. (2018) · Transportation Research Part C Emerging Technologies · doi:10.1016/j.trc.2018.04.005 · Cited by 210 · see citing works
Rahman, M. M., & Thill, J. (2023) · Sustainable Cities and Society · doi:10.1016/j.scs.2023.104649 · Cited by 182 · see citing works
Caird, J. K., Simmons, S. M., Wiley, K., Johnston, K. A., & Horrey, W. J. (2018) · Human Factors The Journal of the Human Factors and Ergonomics Society · doi:10.1177/0018720817748145 · Cited by 180 · see citing works
Safety benefits of arterials’ crash risk under connected and automated vehicles
Rahman, M. S., Abdel-Aty, M. A., Lee, J. J., et al. (2019) · Transportation Research Part C Emerging Technologies · doi:10.1016/j.trc.2019.01.029 · Cited by 163 · see citing works
A Survey on Automated Driving System Testing: Landscapes and Trends
Tang, S., Zhang, Z., Zhang, Y., Zhou, J., Guo, Y. R., Liu, S., Guo, S., Li, Y., Ma, L., Xue, Y., et al. (2023) · ACM Transactions on Software Engineering and Methodology · doi:10.1145/3579642 · Cited by 162 · see citing works
Connected and Autonomous Vehicles and Infrastructures: A Literature Review
Rana, M. M., & Hossain, K. (2021) · International Journal of Pavement Research and Technology · doi:10.1007/s42947-021-00130-1 · Cited by 160 · see citing works
Xu, C., Ding, Z., Wang, C., & Li, Z. (2019) · Journal of Safety Research · doi:10.1016/j.jsr.2019.09.001 · Cited by 146 · see citing works
Learning naturalistic driving environment with statistical realism
Yan, X.-T., Zou, Z., Feng, S., Zhu, H., Sun, H.-W., & Liu, H. X. (2023) · Nature Communications · doi:10.1038/s41467-023-37677-5 · Cited by 145 · see citing works
Simmons, S. M., Hicks, A., & Caird, J. K. (2015) · Accident Analysis & Prevention · doi:10.1016/j.aap.2015.11.015 · Cited by 143 · see citing works
Sinha, A., Chand, S., Wijayaratna, K. P., Virdi, N., & Dixit, V. V. (2020) · Accident Analysis & Prevention · doi:10.1016/j.aap.2020.105567 · Cited by 132 · see citing works
Lee, D., & Hess, D. J. (2020) · Transportation Research Part A Policy and Practice · doi:10.1016/j.tra.2020.03.026 · Cited by 112 · see citing works
Sohrabi, S., Khodadadi, A., Mousavi, S. M., Dadashova, B., & Lord, D. (2021) · Accident Analysis & Prevention · doi:10.1016/j.aap.2021.106003 · Cited by 105 · see citing works
Safety assessment of highly automated driving systems in test tracks: A new framework
Feng, S., Feng, Y., Yan, X., et al. (2020) · Accident Analysis & Prevention · doi:10.1016/j.aap.2020.105664 · Cited by 80 · see citing works
Liu, Q., Wang, X., Liu, S., Yu, C., & Glaser, Y. (2024) · Accident Analysis & Prevention · doi:10.1016/j.aap.2023.107383 · Cited by 74 · see citing works
Self-citationXiao, G., Lee, J. J., Jiang, Q., Huang, H., Abdel-Aty, M. A., & Wang, L. E. (2021) · Accident Analysis & Prevention · doi:10.1016/j.aap.2021.106234 · Cited by 71 · see citing works
Multi-type Bayesian hierarchical modeling of traffic conflict extremes for crash estimation
Fu, C., Sayed, T., & Zheng, L. (2021) · Accident Analysis & Prevention · doi:10.1016/j.aap.2021.106309 · Cited by 71 · see citing works
Astarita, V., & Giofrè, V. P. (2019) · Simulation Modelling Practice and Theory · doi:10.1016/j.simpat.2019.03.003 · Cited by 67 · see citing works
Alozi, A. R., & Hussein, M. (2022) · Analytic Methods in Accident Research · doi:10.1016/j.amar.2022.100230 · Cited by 65 · see citing works
On the Implementation of Behavior Trees in Robotics
Colledanchise, M., & Natale, L. (2021) · IEEE Robotics and Automation Letters · doi:10.1109/lra.2021.3087442 · Cited by 64 · see citing works
Wijayaratna, K. P., Cunningham, M. L., Regan, M., Jian, S., Chand, S., & Dixit, V. V. (2019) · Accident Analysis & Prevention · doi:10.1016/j.aap.2019.04.017 · Cited by 59 · see citing works
Regulatory governance in emerging technologies: The case of autonomous vehicles in Sweden and Norway
Hansson, L. (2020) · Research in Transportation Economics · doi:10.1016/j.retrec.2020.100967 · Cited by 56 · see citing works
Kolekar, S., Petermeijer, B., Boer, E. R., de Winter, J., & Abbink, D. A. (2021) · Transportation Research Part C Emerging Technologies · doi:10.1016/j.trc.2021.103428 · Cited by 53 · see citing works
Freeman, J., & Rakotonirainy, A. (2015) · Accident Analysis & Prevention · doi:10.1016/j.aap.2015.01.015 · Cited by 53 · see citing works
Performance Evaluation of Data Dissemination Protocols for Connected Autonomous Vehicles
Malik, F., Khattak, H. A., Almogren, A., et al. (2020) · IEEE Access · doi:10.1109/access.2020.3006040 · Cited by 50 · see citing works
When the automated driving system fails: Dynamics of public responses to automated vehicles
Xu, Z., Jiang, Z., Wang, G., Wang, R., Li, T., Liu, J., Zhang, Y., & Liu, P. (2021) · Transportation Research Part C Emerging Technologies · doi:10.1016/j.trc.2021.103271 · Cited by 49 · see citing works
Self-citationChen, P., Ni, H., Wang, L., et al. (2024) · Accident Analysis & Prevention · doi:10.1016/j.aap.2024.107530 · Cited by 47 · see citing works
Sørensen, J. V., Ma, Z. G., & Jôrgensen, B. N. (2022) · Energy Informatics · doi:10.1186/s42162-022-00227-2 · Cited by 41 · see citing works
Xu, Z., Zheng, N., Lv, Y., Fang, Y., & Vu, H. L. (2023) · Transportation Research Part C Emerging Technologies · doi:10.1016/j.trc.2023.104451 · Cited by 37 · see citing works
Self-citationXu, Z., Zheng, N., Logan, D. B., & Vu, H. L. (2023) · Accident Analysis & Prevention · doi:10.1016/j.aap.2023.107194 · Cited by 36 · see citing works
Self-citationReview of driving-behaviour simulation: VISSIM and artificial intelligence approach
Al-Msari, H., Koting, S. B., Ahmed, A. N., & El‐Shafie, A. (2024) · Heliyon · doi:10.1016/j.heliyon.2024.e25936 · Cited by 34 · see citing works
DECISIONS TO BREAK OR ADHERE TO THE RULES OF THE ROAD, VIEWED FROM THE RATIONAL CHOICE PERSPECTIVE
Corbett, C., & Simon, F. (1992) · The British Journal of Criminology · doi:10.1093/oxfordjournals.bjc.a048256 · Cited by 32 · see citing works
Abdel-Aty, M. A., Cai, Q., Wu, Y., & Zheng, O. (2022) · Accident Analysis & Prevention · doi:10.1016/j.aap.2022.106797 · Cited by 31 · see citing works
Xu, Z., Fang, Y., Zheng, N., & Vu, H. L. (2022) · Journal of Intelligent and Connected Vehicles · doi:10.1108/jicv-05-2022-0017 · Cited by 29 · see citing works
Self-citationInteractive Left-Turning of Autonomous Vehicles at Uncontrolled Intersections
Sun, C., Leng, J., & Lu, B. (2022) · IEEE Transactions on Automation Science and Engineering · doi:10.1109/tase.2022.3227964 · Cited by 28 · see citing works
Siebke, C., Mai, M., & Prokop, G. (2022) · IEEE Transactions on Intelligent Transportation Systems · doi:10.1109/tits.2022.3220961 · Cited by 27 · see citing works
Safety Testing of Automated Driving Systems: A Literature Review
Khan, F., Falco, M., Anwar, H., & Pfahl, D. (2023) · IEEE Access · doi:10.1109/access.2023.3327918 · Cited by 25 · see citing works
Impediments to Environmental Awareness in Autonomous Driving Systems and its Effect on User Adoption
Xu, Z., Wang, C., Jiang, T., Liu, Z., & Zheng, N. (2024) · IEEE Transactions on Intelligent Vehicles · doi:10.1109/tiv.2024.3373773 · Cited by 24 · see citing works
Self-citationYu, R., & Li, S. (2021) · Accident Analysis & Prevention · doi:10.1016/j.aap.2021.106537 · Cited by 23 · see citing works
Ni, H., Yu, G., Chen, P., Zhou, B., Liao, Y., & Li, H. (2024) · IEEE Transactions on Vehicular Technology · doi:10.1109/tvt.2024.3377288 · Cited by 22 · see citing works
Yang, S., Huang, Y., Li, L., Feng, S., Na, X., Chen, H., & Khajepour, A. (2024) · IEEE Intelligent Transportation Systems Magazine · doi:10.1109/mits.2023.3345930 · Cited by 20 · see citing works
This Is How To Be a Rule Breaker
Wirth, R., Foerster, A., Herbort, O., Kunde, W., & Pfister, R. (2018) · Advances in Cognitive Psychology · doi:10.5709/acp-0235-2 · Cited by 20 · see citing works
Test and Evaluation of Connected and Autonomous Vehicles in Real-world Scenarios
Pereira, J., Premebida, C., Asvadi, A., et al. (2019) · IEEE Intelligent Vehicles Symposium · doi:10.1109/ivs.2019.8814032 · Cited by 19 · see citing works
Assessing the impact of passenger compliance behavior in CAVs on environmental benefits
Xu, Z., Zheng, Z., Xiao, D., Tu, R., Ma, W., & Zheng, N. (2024) · Transportation Research Part D Transport and Environment · doi:10.1016/j.trd.2024.104278 · Cited by 16 · see citing works
Self-citationA Qualitative and Quantitative Analysis of Real Time Traffic Information Providers
Bauer, T. P., Edinger, J., & Becker, C. (2019) · IEEE International Conference on Pervasive Computing and Communications Workshops (PerCom Workshops) · doi:10.1109/percomw.2019.8730795 · Cited by 8 · see citing works
Devalla, J. (2018) · DOAJ (DOAJ: Directory of Open Access Journals) · Cited by 2 · see citing works
Automated System for Traffic Control and Management
Ranjane, H., Talware, R., Bang, A. V., et al. (2023) · International Conference on I-SMAC (IoT in Social, Mobile, Analytics and Cloud) (I-SMAC) · doi:10.1109/i-smac58438.2023.10290157 · Cited by 1 · see citing works
Flagged first, then by citations
Research works printed but not linked: 1
- Wiedemann, 1992, Microscopic traffic simulation: the simulation system MISSION, background and actual state, Project ICARUS (V1052) Final Report, 2, 1
Cited by
Sorted by citations
Xu, Z., Zheng, N., Fang, Y., & Vu, H. L. (2025) · Transportation Research Part C: Emerging Technologies · doi:10.1016/j.trc.2025.105367 · Cited by 6 · see citing works
Self-citation
- Authors
- Xu, Z., Wang, X., Wang, X., & Zheng, N.
- Affiliations
- Monash University (AU)
- Tongji University (CN)
- Corresponding author
- Xu, Zheng
- ORCID
- Venue
- Accident Analysis & Prevention
- Publisher
- Elsevier BV
- Published
- 2025-06
- Volume
- 215
- Pages
- 108011
- ISSN
- 0001-4575 (ISSN-L)
- OpenAlex
- W4408558711
- Semantic Scholar
- 26f715d43c3428ddb4061e9699b8987ce38f38ff
- Cited by
- 29
- References
- 54
- Citations by year
- 2026: 17 · 2025: 12
- FWCI
- 10.77
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Accident Analysis & Prevention (publishedVersion, cc-by)
- PubMed (publishedVersion)
- Topics
- Physical Sciences › Engineering › Control and Systems Engineering › Traffic control and management
- Physical Sciences › Engineering › Safety, Risk, Reliability and Quality › Traffic and Road Safety
- Physical Sciences › Engineering › Automotive Engineering › Autonomous Vehicle Technology and Safety
- Keywords
- connected and autonomous vehicles, CAV penetration rate, co-simulation, CARLA, microscopic traffic simulation, deep reinforcement learning, Bayesian hierarchical model, intersection conflicts, roundabouts, signalized intersections
- MeSH terms
- Accidents, Traffic, Automation, Automobile Driving, Automobiles, Bayes Theorem, Computer Simulation, Humans, Safety
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review