An ethical trajectory planning algorithm for autonomous vehicles
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Abstract
Abstract With the rise of AI and automation, moral decisions are being put into the hands of algorithms that were formerly the preserve of humans. In autonomous driving, a variety of such decisions with ethical impli-cations are made by algorithms for behavior and trajectory planning. Therefore, we present an ethical trajectory planning algorithm with a framework that aims at a fair distribution of risk among road users. Our implementation incorporates a combination of five essential ethical principles: minimization of the overall risk, priority for the worst-off, equal treatment of people, responsibility, and maximum acceptable risk. To the best of the authors’ knowledge, this is the first ethical algorithm for trajectory planning of autonomous vehicles in line with the 20 recommendations from the EU Commission expert group and with general applicability to various traffic situations. We showcase the ethical behavior of our algorithm in selected scenarios and provide an empirical analysis of the ethical principles in 2000 scenarios. The code used in this research is available as open-source software.
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Prior ethical AV approaches often rely on pre-defined rankings, hand-tuned parameters, or fixed weighting schemes, which may not adapt well to heterogeneous, real-world traffic.
“At the same time, they often rely on pre-defined rankings, hand-tuned parameters, or fixed weighting schemes, which may not adapt well to heterogeneous, real-world traffic.”
From Ethics-Aware Safe Reinforcement Learning for Rare-Event Risk Control in Interactive Urban Driving (2026) · cites this paper as [11]
The Discussion (page unavailable) says that a particular set of weighting factors may not apply universally because countries, cultures, and individuals may demand different ethical emphases. This supports the concern about fixed weights, but the paper does not establish that prior ethical AV approaches often use pre-defined rankings or hand-tuned parameters, or that those approaches fail in heterogeneous real-world traffic. (LLM, conf=0.78)
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Cites
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Cited by
Sorted by citations
Ethics-Aware Safe Reinforcement Learning for Rare-Event Risk Control in Interactive Urban Driving
Li, D., & Okhrin, O. (2026) · IEEE Transactions on Pattern Analysis and Machine Intelligence · doi:10.1109/tpami.2026.3708405
- Authors
- Geisslinger, M., Poszler, F., & Lienkamp, M.
- Affiliations
- Technical University of Munich (DE)
- Corresponding author
- Geisslinger, Maximilian
- Venue
- Nature Machine Intelligence
- Published
- 2023-02-02
- Volume
- 5
- Issue
- 2
- Pages
- 137-144
- ISSN
- 2522-5839 (ISSN-L)
- OpenAlex
- W4318982572
- Cited by
- 140
- References
- 3
- Citations by year
- 2026: 42 · 2025: 44 · 2024: 39 · 2023: 15
- FWCI
- 9.72
- Type
- journal article
- Language
- en
- Open access
- green
- doi.org
- Licence
- Locations
- Nature Machine Intelligence (publishedVersion, public-domain)
- Research Square (acceptedVersion, cc-by)
- arXiv (Cornell University) (submittedVersion, cc-by)
- mediaTUM (Technical University of Munich) (submittedVersion)
- arXiv (Cornell University) (cc-by)
- Funders
- The authors received financial support from the Technical University of Munich — Institute for Ethics in Artificial Intelligence (IEAI).
- Topics
- Physical Sciences › Engineering › Automotive Engineering › Autonomous Vehicle Technology and Safety
- Social Sciences › Safety Research › Ethics and Social Impacts of AI
- Physical Sciences › Engineering › Safety, Risk, Reliability and Quality › Safety Systems Engineering in Autonomy
- Keywords
- autonomous vehicles, algorithmic ethics, ethical principles, equal treatment, responsibility, maximum acceptable risk, risk minimization
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