Robust Path Tracking Control of an E-Corner Vehicle under Nonlinear Tire Dynamics Using Soft Actor-Critic

Eun-jin Jang; Jae-poong Lee; Hee-seung Lim

doi:10.22680/kasa2026.18.1.099

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Robust Path Tracking Control of an E-Corner Vehicle under Nonlinear Tire Dynamics Using Soft Actor-Critic

31 March 2026. pp. 99-109

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Abstract

This paper aims to design a robust path tracking controller for E-Corner vehicles operating under environmental uncertainties and varying driving conditions. To this end, we build a vehicle dynamics simulation incorporating the Fiala tire model with a compact parameter set to capture realistic lateral tire behavior. A steering policy is then trained using Soft Actor-Critic, an off-policy reinforcement learning algorithm that maximizes both expected return and policy entropy, thereby promoting robust exploration and stable learning in continuous action spaces. The entropy-regularized objective of SAC enables the policy to remain resilient to modeling uncertainties and variations in vehicle dynamics, which are critical in path tracking tasks under diverse operating conditions. The vehicle model adopts a steering configuration that includes both front-wheel steering and rear-wheel steering to improve yaw rate tracking performance during path tracking maneuvers. Simulation results show that the learned agent maintains stable tracking performance under various conditions, achieving a yaw rate tracking error as low as 0.0023 rad/s at a vehicle speed of 20 m/s. In particular, a policy trained under a weave scenario also exhibits stable path tracking performance when deployed on trajectories acquired from the KIAPI Proving Ground, indicating good transferability beyond the training conditions and improved robustness to unseen path profiles.

Keywords

Reinforcement learning

Path tracking

Soft actor-critic

Nonlinear tire model

E-corner

References

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Information

Publisher :Korean Auto-vehicle Safety Association
Publisher(Ko) :한국자동차모빌리티안전학회
Journal Title :Journal of Auto-vehicle Safety Association
Journal Title(Ko) :자동차안전학회지
Volume : 18
No :1
Pages :99-109
Received Date : 2026-01-19
Revised Date : 2026-02-06
Accepted Date : 2026-02-11
DOI :https://doi.org/10.22680/kasa2026.18.1.099

Journal of Auto-vehicle Safety Association ISSN:2005-9396(Print) 자동차안전학회지

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