Semi-autonomous Collision Avoidance Flight of UAV Under Bridge by Using Two-dimensional Laser Range Finder with Mirrors

Abstract

This paper presents a semi-autonomous collision avoidance flight using two-dimesnional laser range finder with mirrors. The sensor used in this research scans over horizontal and vertical directions simultaneously. We develop obstacle detection and height estimation system for inspection under bridge by using this sensor. The hough transform is used for the obstacle detection in the flight direction. For the height estimation under bridge, we develop a method to estimate the relative distance between the UAV and bridge even in the case when the surface of the bridge is rough. Flight experiment is carried out to verify the validity of developed system.