Epistemic Uncertainty Aware Semantic Localization and Mapping for Inference and Belief Space Planning

TL;DR

This paper introduces a unified Bayesian framework for semantic SLAM and belief space planning that explicitly models and reasons about epistemic and localization uncertainties, improving autonomous object classification and mapping.

Contribution

It presents two novel methods, MH and JLP, for maintaining joint beliefs over poses and class probabilities, incorporating epistemic uncertainty into semantic SLAM and planning.

Findings

Developed a Bayesian approach to handle epistemic uncertainty in semantic SLAM.

Proposed two methods, MH and JLP, for joint belief maintenance.

Extended methods to belief space planning with an information-theoretic reward.

Abstract

We investigate the problem of autonomous object classification and semantic SLAM, which in general exhibits a tight coupling between classification, metric SLAM and planning under uncertainty. We contribute a unified framework for inference and belief space planning (BSP) that addresses prominent sources of uncertainty in this context: classification aliasing (classier cannot distinguish between candidate classes from certain viewpoints), classifier epistemic uncertainty (classifier receives data "far" from its training set), and localization uncertainty (camera and object poses are uncertain). Specifically, we develop two methods for maintaining a joint distribution over robot and object poses, and over posterior class probability vector that considers epistemic uncertainty in a Bayesian fashion. The first approach is Multi-Hybrid (MH), where multiple hybrid beliefs over poses and classes are maintained to approximate the joint belief over poses and posterior class probability. The second approach is Joint Lambda Pose (JLP), where the joint belief is maintained directly using a novel JLP factor. Furthermore, we extend both methods to BSP, planning while reasoning about future posterior epistemic uncertainty indirectly, or directly via a novel information-theoretic reward function. Both inference methods utilize a novel viewpoint-dependent classifier uncertainty model that leverages the coupling between poses and classification scores and predicts the epistemic uncertainty from certain viewpoints. In addition, this model is used to generate predicted measurements during planning. To the best of our knowledge, this is the first work that reasons about classifier epistemic uncertainty within semantic SLAM and BSP.