๐ค AI Summary
This work addresses the challenge of obtaining accurate and temporally smooth localization covariance estimates for high-dynamic autonomous race cars in GNSS-degraded environments, where poor uncertainty quantification compromises control stability. To this end, the authors propose the LACE framework, whichโ for the first timeโmodels covariance dynamics as an exponentially stable controlled dynamical system. By integrating deep neural networks with attention mechanisms, LACE learns temporal covariance evolution from environmental features, while rigorously enforcing exponential stability and smoothness through spectral constraints grounded in contraction theory. This approach achieves tight coupling between environmental perception and state estimation. Experimental validation on the AV-24 racing platform demonstrates that, under GNSS-degraded conditions, LACE significantly improves localization accuracy, yields more reliable and smoother uncertainty estimates, and thereby enhances the robustness of the downstream control system.
๐ Abstract
Ensuring accurate and stable state estimation is a challenging task crucial to safety-critical domains such as high-speed autonomous racing, where measurement uncertainty must be both adaptive to the environment and temporally smooth for control. In this work, we develop a learning-based framework, LACE, capable of directly modeling the temporal dynamics of GNSS measurement covariance. We model the covariance evolution as an exponentially stable dynamical system where a deep neural network (DNN) learns to predict the system's process noise from environmental features through an attention mechanism. By using contraction-based stability and systematically imposing spectral constraints, we formally provide guarantees of exponential stability and smoothness for the resulting covariance dynamics. We validate our approach on an AV-24 autonomous racecar, demonstrating improved localization performance and smoother covariance estimates in challenging, GNSS-degraded environments. Our results highlight the promise of dynamically modeling the perceived uncertainty in state estimation problems that are tightly coupled with control sensitivity.