# Mutual information-based hierarchical NBV decision for active semantic visual SLAM under dynamic environments

## TL;DR

This paper introduces a new active SLAM method that improves robot mapping in dynamic environments by using mutual information and better path planning.

## Contribution

A real-time mutual information-based active SLAM approach with two NBV decision modules for dynamic environments.

## Key findings

- The method effectively excludes dynamic objects from mapping while maintaining robustness.
- Experiments show improved mapping efficiency and tracking in simulated and real-world scenarios.
- The algorithm is suitable for real-world deployment in dynamic settings.

## Abstract

Active Simultaneous Localization and Mapping (A-SLAM) technology enables a robot to autonomously plan its movements to build a comprehensive and accurate map of its surroundings. However, most existing SLAM algorithms are not robust in dynamic environments, as moving objects can negatively impact mapping and localization accuracy, making it difficult for the robot to keep tracking and fully understand its environment. While some semantic SLAM methods can identify and exclude dynamic objects, in active SLAM, excluding features without proper path planning carries significant risks of losing track. In this work, we propose a real-time mutual information-based active SLAM approach designed to enhance robustness in dynamic environments. The proposed method not only excludes dynamic objects from the mapping process but also integrates two Next-Best-View (NBV) decision modules to improve path planning and maintain robustness. This feature allows for improved mapping efficiency and robustness to avoid losing tracking in dynamic environments. Experiments conducted in two simulated environments and one real-world scenario demonstrate that the proposed active SLAM algorithm maintains its robustness and efficiency in dynamic environments, and is deployable in real applications.