Particle Filter Networks: End-to-End Probabilistic Localization From Visual Observations

Particle filters sequentially approximate posterior distributions by sampling representative points and updating them independently. The idea is applied in various domains, e.g. reasoning with uncertainty in robotics. A remaining challenge is constructing probabilistic models of the system, which can be especially hard for complex sensors, e.g. a camera. We introduce the Particle Filter Networks (PF-nets) that encode both a learned probabilistic system model and the particle filter algorithm in a single neural network architecture. The unified representation allows learning models end-to-end, circumventing the difficulties of conventional model-based methods. We applied PF-nets to a challenging visual localization task that requires matching visual features from camera images with the geometry encoded in a 2-D floor map. In preliminary experiments end-to-end PF-nets consistently outperformed alternative learning architectures, as well as conventional model-based methods.