Non-Line-of-Sight Tracking and Mapping with an Active Corner Camera

TL;DR

This paper introduces a novel active NLOS imaging method capable of accurately reconstructing moving objects and mapping stationary scenes without laser scanning, enhancing indoor situational awareness.

Contribution

It presents a new approach that models optical responses more completely and reconstructs dynamic and static hidden scenes without multiple illumination positions.

Findings

Accurate reconstruction of moving objects in NLOS scenarios.

Effective mapping of stationary hidden scenes.

No need for laser scanning or multiple illumination points.

Abstract

The ability to form non-line-of-sight (NLOS) images of changing scenes could be transformative in a variety of fields, including search and rescue, autonomous vehicle navigation, and reconnaissance. Most existing active NLOS methods illuminate the hidden scene using a pulsed laser directed at a relay surface and collect time-resolved measurements of returning light. The prevailing approaches include raster scanning of a rectangular grid on a vertical wall opposite the volume of interest to generate a collection of confocal measurements. These are inherently limited by the need for laser scanning. Methods that avoid laser scanning track the moving parts of the hidden scene as one or two point targets. In this work, based on more complete optical response modeling yet still without multiple illumination positions, we demonstrate accurate reconstructions of objects in motion and a 'map' of the stationary scenery behind them. The ability to count, localize, and characterize the sizes of hidden objects in motion, combined with mapping of the stationary hidden scene, could greatly improve indoor situational awareness in a variety of applications.