Laser Radar based Vehicle Localization in GPS Signal Blocked Areas

Reliable vehicle localization is a basic requirement in many applications in transportation field. GPS-based localization is quite popular nowadays. However, in urban environments applications, signal of GPS is often blocked by surrounding objects like high-rise buildings, tunnels, overhead roads, etc, making localization information unavailable. This paper proposed a laser radar based map matching approach to address this problem, especially when GPS signal blocked area is large. The proposed approach includes mapping and localization. In the mapping, after map initialization sensor data constraints are linearized to formulate an optimal linear estimation based map optimization framework, which can improve map accuracy effectively. In the localization, vehicle pose is estimated by matching the current laser scan with the best submap and by a UKF (Unscented Kalman Filter) based fusion strategy. Results from both synthetic and real experiments show good performance of the proposed approach. Keywords: GPS Signal Blocked, Vehicle Localization, Mapping, Map Optimizatio