Automatic Operation of an Articulated Dump Truck: State Estimation by Combined QZSS CLAS and Moving-Base RTK Using Multiple GNSS Receivers

TL;DR

This paper presents a novel GNSS-based method for automatic dump truck operation that combines QZSS CLAS and moving-base RTK to achieve high-accuracy state estimation without relying on reference stations, suitable for mountainous areas.

Contribution

It introduces a state estimation approach combining CLAS and RTK-GNSS via factor graph optimization, enabling accurate dump truck operation without reference stations in challenging terrains.

Findings

Achieves RTK-GNSS level accuracy without reference stations.

Effective in mountainous and unstable network environments.

Validated through real-world evaluation tests.

Abstract

Labor shortage due to the declining birth rate has become a serious problem in the construction industry, and automation of construction work is attracting attention as a solution to this problem. This paper proposes a method to realize state estimation of dump truck position, orientation and articulation angle using multiple GNSS for automatic operation of dump trucks. RTK-GNSS is commonly used for automation of construction equipment, but in mountainous areas, mobile networks often unstable, and RTK-GNSS using GNSS reference stations cannot be used. Therefore, this paper develops a state estimation method for dump trucks that does not require a GNSS reference station by using the Centimeter Level Augmentation Service (CLAS) of the Japanese Quasi-Zenith Satellite System (QZSS). Although CLAS is capable of centimeter-level position estimation, its positioning accuracy and ambiguity fix rate are lower than those of RTK-GNSS. To solve this problem, we construct a state estimation method by factor graph optimization that combines CLAS positioning and moving-base RTK-GNSS between multiple GNSS antennas. Evaluation tests under real-world environments have shown that the proposed method can estimate the state of dump trucks with the same accuracy as conventional RTK-GNSS, but does not require a GNSS reference station.