MADOCA-PPP/INS Tightly Coupled Integration Based on RTKLIB for Moving Vehicles

JAXA developed Multi-GNSS Advanced Demonstration tool for Orbit and Clock Analysis precise GNSS orbit and clock determination tool (MADOCA) and the software capable of its precise point positioning (MADOCA-PPP), which is based on RTKLIB, an open-source program package for GNSS positioning. The integration of MADOCA-PPP and inertial navigation system (INS) has the potential to perform precise and robust navigation for moving vehicles. The purpose of this study is to show and evaluate the algorithm of the INS tightly coupled integration using the MADOCA-PPP. In observation data obtained with a car, the proposed method was found to suppress the increase position errors of MADOCA-PPP compared to the case without the IMU sensor or during GNSS observation data loss, with the help of the fine-tuning of the observation error model in the PPP filter and the clock modeling. From these results, the proposed MADOCA-PPP/INS tightly coupled integration based on RTKLIB was found to achieve robust navigation with 20 centimeter-level position accuracy. The availability of QZSS MADOCA-PPP would be limited in comparison with global PPP services however, MADOCA-PPP/INS is expected to work as the more continuous and precise real-time navigation of PPP under the limited sky in multipath environment.