Panoramik görüntülerde gökyüzü sınır çizgisini kullanarak hareketli robotlar için yer kestirimi

Abstract

Highlights:Graphical/Tabular Abstract  Signal extraction from skylines in panoramic images to be used in localization  Use of skyline in mobile robot localization  Applicability of the proposed method on small-scale mobile robots operating outdoors Figure A. Skylines found on photos that are taken from the same spot at different times Purpose: Variety of small size and low-cost panoramic cameras are available on the market. The purpose of this work is to investigate the usability of these panoramic cameras for localization purposes especially in small-scale outdoor mobile robots. It should be noted that many mobile robots are territorial (i.e. operate in a bounded region), hence reliable map-based local navigation enhances the usability of such robots. Figure A illustrates the observation that motivates this research: Skylines on panoramic images that are captured from the same reference point at different times under different lighting conditions turn out to be very similar. Using the obvious fact that, skyline will gradually change as one moves away from this reference point, the skyline obtained at the reference point can be used as a signature signal that defines / identifies this point. Hence, skylines can be used for localization. In this study, a way of extracting signature signals from panoramic images is proposed. Signals extracted from consecutive points on a line is used to form a map. Once the map is formed, test images that are around this line are acquired at different times under different lighting conditions. The skyline signal extracted from a test image is then compared to the ones on the map using a proposed similarity measure. The map image that yields the maximum similarity that is above a certain threshold is associated with the test image and test image is considered to be localized. The study also investigates the effect of image resolution on both localization performance and computation time. Along with practical guidelines for applying the proposed method in practice, test images and source codes are provided as well. Theory and Methods: Results:Through rigorous experiments (two of which are given in the paper) it is shown that if a region is properly mapped, sub-meter localization accuracy is possible. Conclusion:What differentiates this work from others in the literature is not that skyline is used for localization purposes, but it is shown that using readily available and low cost panoramic cameras sub-meter localization can be achieved, hence, the proposed method can be used in mobile robots. Given the small size of these cameras, proposed method offers a practical localization method for small-scale outdoor robots. The dependency of the skyline being detectable by the preferred camera imposes the limitation that proposed method cannot be used during the night.Advances in robotics liberated robots from factory floors by the end of 20th century. Use of robots in our daily lives is only expected to increase in time. Robots, while relieving us of the burden of tedious, hard and dang...