# Renderable Neural Radiance Map for Visual Navigation

## TL;DR

This paper introduces the RNR-Map, a novel neural radiance map for visual navigation that encodes environmental visual information for improved localization and navigation, demonstrating superior performance in various scenarios.

## Contribution

The paper presents the RNR-Map, a new renderable neural radiance map that effectively encodes visual environment data for navigation tasks, with frameworks for localization and navigation.

## Key findings

- RNR-Map-based localization achieves fast, accurate results with robustness to environmental changes.
- The navigation framework outperforms existing methods, especially in challenging scenarios.
- Achieved 65.7% success rate in curved scenarios, surpassing previous state-of-the-art by 18.6%.

## Abstract

We propose a novel type of map for visual navigation, a renderable neural radiance map (RNR-Map), which is designed to contain the overall visual information of a 3D environment. The RNR-Map has a grid form and consists of latent codes at each pixel. These latent codes are embedded from image observations, and can be converted to the neural radiance field which enables image rendering given a camera pose. The recorded latent codes implicitly contain visual information about the environment, which makes the RNR-Map visually descriptive. This visual information in RNR-Map can be a useful guideline for visual localization and navigation. We develop localization and navigation frameworks that can effectively utilize the RNR-Map. We evaluate the proposed frameworks on camera tracking, visual localization, and image-goal navigation. Experimental results show that the RNR-Map-based localization framework can find the target location based on a single query image with fast speed and competitive accuracy compared to other baselines. Also, this localization framework is robust to environmental changes, and even finds the most visually similar places when a query image from a different environment is given. The proposed navigation framework outperforms the existing image-goal navigation methods in difficult scenarios, under odometry and actuation noises. The navigation framework shows 65.7% success rate in curved scenarios of the NRNS dataset, which is an improvement of 18.6% over the current state-of-the-art. Project page: https://rllab-snu.github.io/projects/RNR-Map/