Vision-model-based Real-time Localization of Unmanned Aerial Vehicle for Autonomous Structure Inspection under GPS-denied Environment

TL;DR

This paper introduces a real-time UAV localization method using only a single camera, enabling autonomous structure inspections in GPS-denied environments, thus expanding UAV application scope.

Contribution

It presents a novel vision-based self-positioning approach that eliminates the need for GPS and additional sensors, suitable for indoor and GPS-denied outdoor inspections.

Findings

Successful indoor test validation of the method

Continuous real-time pose estimation achieved

Potential for broader UAV inspection applications

Abstract

UAVs have been widely used in visual inspections of buildings, bridges and other structures. In either outdoor autonomous or semi-autonomous flights missions strong GPS signal is vital for UAV to locate its own positions. However, strong GPS signal is not always available, and it can degrade or fully loss underneath large structures or close to power lines, which can cause serious control issues or even UAV crashes. Such limitations highly restricted the applications of UAV as a routine inspection tool in various domains. In this paper a vision-model-based real-time self-positioning method is proposed to support autonomous aerial inspection without the need of GPS support. Compared to other localization methods that requires additional onboard sensors, the proposed method uses a single camera to continuously estimate the inflight poses of UAV. Each step of the proposed method is discussed in detail, and its performance is tested through an indoor test case.