Real-time global localization of intelligent road vehicles in lane-level via lane marking detection and shape registration

In this paper, we propose an accurate and real-time positioning method for intelligent road vehicles in urban environments. The proposed method uses a robust lane marking detection algorithm, as well as an efficient shape registration algorithm between the detected lane markings and a GPS based road shape prior, to improve the robustness and accuracy of global localization of a road vehicle. We exploit both the state-of-the-art technologies of visual localization based on lane marking detection and the wide availability of Global Positioning System (GPS) based localization. We show that by formulating the positioning problem in a relative sense, we can estimate the vehicle localization in real-time and bound its absolute error in centimeter-level by a cross validation scheme. The validation scheme integrates the vision based lane marking detection with the shape registration, and improves the performance of the overall localization system. The GPS localization can be refined by using lane marking detection when the GPS suffers from frequent satellite signal masking or blockage, while lane marking detection is validated and completing by the GPS based road shape prior when it does not work well in adverse weather conditions or with poor lane signature. We extensively evaluate the proposed method with a single forward-looking camera mounted on an autonomous vehicle which travels at 60km/h through several urban street scenes.