Robust Lane Change Decision Making for Autonomous Vehicles: An
Observation Adversarial Reinforcement Learning Approach
Abstract
Reinforcement learning holds the promise of allowing autonomous vehicles
to learn complex decision making behaviors through interacting with
other traffic participants. However, many real-world driving tasks
involve unpredictable perception errors or measurement noises which may
mislead an autonomous vehicle into making unsafe decisions, even cause
catastrophic failures. In light of these risks, to ensure safety under
perception uncertainty, autonomous vehicles are required to be able to
cope with the worst case observation perturbations. Therefore, this
paper proposes a novel observation adversarial reinforcement learning
approach for robust lane change decision making of autonomous vehicles.
A constrained observation-robust Markov decision process is presented to
model lane change decision making behaviors of autonomous vehicles under
policy constraints and observation uncertainties. Meanwhile, a
black-box attack technique based on Bayesian optimization is implemented
to approximate the optimal adversarial observation perturbations
efficiently. Furthermore, a constrained observation-robust actor-critic
algorithm is advanced to optimize autonomous driving lane change
policies while keeping the variations of the policies attacked by the
optimal adversarial observation perturbations within bounds. Finally,
the robust lane change decision making approach is evaluated in three
stochastic mixed traffic flows based on different densities. The results
demonstrate that the proposed method can not only enhance the
performance of an autonomous vehicle but also improve the robustness of
lane change policies against adversarial observation perturbations.