SmartRainNet: Uncertainty Estimation For Laser Measurement in Rain.

Adverse weather has raised a big challenge for autonomous vehicles. Unreliable measurements due to sensor degradation could seriously affect the performance of autonomous driving tasks, such as perception and localization. In this work, we study sensor degradation in rainy weather and present a novel method that evaluates the uncertainty for each laser measurement from a 3D LiDAR. With uncertainty estimation, downstream tasks that rely on LiDAR input (e.g., perception or localization) can increase their reliability by adjusting their reliance on laser measurements with varying fidelity. Alternatively, uncertainty estimation can be used for sensor performance evaluation. Our proposed method, SmartRainNet, uses an attention-based Mixture Density Network to model the dependence between neighboring laser measurements and then calculate the probability density for each laser measurement as an uncertainty score. We evaluate SmartRainNet on synthetic and naturalistic sensor degradation datasets and provide qualitative and quantitative results to demonstrate the effectiveness of our method in evaluating uncertainty. Finally, we demonstrate three practical applications of uncertainty estimation to address autonomous driving challenges in rainy weather.