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Can Autonomous Vehicles Identify, Recover From, and Adapt to Distribution Shifts?

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 نشر من قبل Angelos Filos
 تاريخ النشر 2020
  مجال البحث الهندسة المعلوماتية
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Out-of-training-distribution (OOD) scenarios are a common challenge of learning agents at deployment, typically leading to arbitrary deductions and poorly-informed decisions. In principle, detection of and adaptation to OOD scenes can mitigate their adverse effects. In this paper, we highlight the limitations of current approaches to novel driving scenes and propose an epistemic uncertainty-aware planning method, called emph{robust imitative planning} (RIP). Our method can detect and recover from some distribution shifts, reducing the overconfident and catastrophic extrapolations in OOD scenes. If the models uncertainty is too great to suggest a safe course of action, the model can instead query the expert driver for feedback, enabling sample-efficient online adaptation, a variant of our method we term emph{adaptive robust imitative planning} (AdaRIP). Our methods outperform current state-of-the-art approaches in the nuScenes emph{prediction} challenge, but since no benchmark evaluating OOD detection and adaption currently exists to assess emph{control}, we introduce an autonomous car novel-scene benchmark, texttt{CARNOVEL}, to evaluate the robustness of driving agents to a suite of tasks with distribution shifts.



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