The Impact of Adverse Environmental Conditions on Fiducial Marker Detection from Rotorcraft

This paper quantifies the impact of adverse environmental conditions on the detection of fiducial markers (i.e., artificial landmarks) by color cameras mounted on rotorcraft. We restrict our attention to square markers with a black-and-white pattern of grid cells that can be nested to allow detection at multiple scales. These markers have the potential to enhance the reliability of precision takeoff and landing at vertiports by flying vehicles in urban settings. Previous studies have demonstrated high accuracy in pose estimation, primarily relying on image sequences captured indoors using handheld cameras. However, the scope of much of this prior work has been limited to indoor environments. Our work is based on image sequences collected outdoors with cameras mounted on a quadrotor during takeoff and landing operations under adverse environmental conditions that include variations in temperature, illumination, wind speed, and precipitation. We evaluate the marker detection performance based on both the detection rate and the accuracy of pose estimation.