Optical aberrations in autonomous driving: Physics-informed parameterized temperature scaling for neural network uncertainty calibration

TL;DR

This paper introduces a physics-informed calibration method for neural networks in autonomous driving, leveraging optical aberration metrics to improve uncertainty estimates and robustness against dataset shifts caused by optical distortions.

Contribution

It proposes incorporating optical system parameters as physical priors into neural network calibration to enhance uncertainty reliability in autonomous driving perception systems.

Findings

Significantly reduces calibration error under optical aberrations

Improves robustness of uncertainty estimates against dataset shifts

Enables holistic verification of perception systems

Abstract

'A trustworthy representation of uncertainty is desirable and should be considered as a key feature of any machine learning method' (Huellermeier and Waegeman, 2021). This conclusion of Huellermeier et al. underpins the importance of calibrated uncertainties. Since AI-based algorithms are heavily impacted by dataset shifts, the automotive industry needs to safeguard its system against all possible contingencies. One important but often neglected dataset shift is caused by optical aberrations induced by the windshield. For the verification of the perception system performance, requirements on the AI performance need to be translated into optical metrics by a bijective mapping. Given this bijective mapping it is evident that the optical system characteristics add additional information about the magnitude of the dataset shift. As a consequence, we propose to incorporate a physical inductive bias into the neural network calibration architecture to enhance the robustness and the trustworthiness of the AI target application, which we demonstrate by using a semantic segmentation task as an example. By utilizing the Zernike coefficient vector of the optical system as a physical prior we can significantly reduce the mean expected calibration error in case of optical aberrations. As a result, we pave the way for a trustworthy uncertainty representation and for a holistic verification strategy of the perception chain.