Odometer, low-cost inertial sensors, and four-GNSS data to enhance PPP and attitude determination

• Published in: GPS solutions Vol. 22; no. 3
• Main Authors: Gao, Zhouzheng, Ge, Maorong, Li, You, Chen, Qijin, Zhang, Quan, Niu, Xiaoji, Zhang, Hongping, Shen, Wenbin, Schuh, Harald
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.07.2018
• Subjects: Atmospheric Sciences; Automotive Engineering; Earth and Environmental Science; Earth Sciences; Electrical Engineering; Geophysics/Geodesy; Original Article; Space Exploration and Astronautics; Space Sciences (including Extraterrestrial Physics; Global navigation satellite systems (GNSSs); Odometer; Attitude determination; Low-cost inertial navigation system (INS); Precise point positioning (PPP)
• ISSN: 1080-5370; 1521-1886
• DOI: 10.1007/s10291-018-0725-y

To upgrade the positioning accuracy, re-initialization speed, and attitude determination performance of precise point positioning (PPP) in dynamic applications, we proposed a multi-sensor fusion system consisting of four global navigation satellite systems (GNSSs), namely GPS, BDS, Galileo, and GLONASS, several low-cost inertial sensors, and an odometer. The study shows that the performance of PPP in terms of continuity, reliability, stability, and re-initialization speed improves by such a multi-sensor fusion system. This manifests itself in a significantly increased accuracy. For position solutions, compared to un-aided PPP solutions, the improvements achieved using low-cost inertial navigation system (INS) are about 36.4, 38.7, and 31.3% in the north, east, and vertical components, respectively, and the improvement using odometer are about 1.58, 0.35, and 4.32% relative to the INS-aided PPP solutions. Moreover, using the odometer can provide more than 2.1, 1.4, and 50.6% attitude improvements for roll, pitch, and heading angles compared to the attitude solutions obtained from the INS-aided PPP system. Under GNSS outage conditions, the mean position improvements using the odometer are about 2.3, 1.8, and 8.7%, with maximum increases of 74.6, 74.7, and 28.3%, and the average attitude improvements are about 4.7, 5.4, and 3.3%, with maximum increases of 36.4, 31.7, and 28.9%, respectively. This means that the odometer can enhance the performance of PPP and PPP/INS integration in challenging dynamic conditions.