Due to the declining birthrate and aging population, the shortage of labor in the construction industry has become a serious problem, and increasing attention has been paid to automation of construction equipment. We focus on the automatic operation of articulated six-wheel dump trucks at construction sites. For the automatic operation of the dump trucks, it is important to estimate the position and the articulated angle of the dump trucks with high accuracy. In this study, we propose a method for estimating the state of a dump truck by using four global navigation satellite systems (GNSSs) installed on an articulated dump truck and a graph optimization method that utilizes the redundancy of multiple GNSSs. By adding real-time kinematic (RTK)-GNSS constraints and geometric constraints between the four antennas, the proposed method can robustly estimate the position and articulation angle even in environments where GNSS satellites are partially blocked. As a result of evaluating the accuracy of the proposed method through field tests, it was confirmed that the articulated angle could be estimated with an accuracy of 0.1${}^{\circ }$ in an open-sky environment and 0.7${}^{\circ }$ in a mountainous area simulating an elevation angle of 45${}^{\circ }$ where GNSS satellites are blocked.

由于出生率下降和人口老龄化，建筑行业劳动力短缺成为严重问题，建筑设备自动化越来越受到重视。我们专注于铰接式六轮自卸车在建筑工地的自动化操作。对于自卸车的自动操作，高精度地估计自卸车的位置和铰接角度非常重要。在这项研究中，我们提出了一种通过使用安装在铰接式自卸车上的四个全球导航卫星系统 (GNSS) 来估计自卸车状态的方法和一种利用多个 GNSS 冗余的图形优化方法。通过在四个天线之间添加实时运动学 (RTK)-GNSS 约束和几何约束，即使在 GNSS 卫星被部分阻挡的环境中，所提出的方法也可以稳健地估计位置和关节角度。通过现场测试评估所提出方法的准确性，结果证实铰接角度的估计精度可以达到 0.1${}^{\circ }$ 在开阔的天空环境和 0.7${}^{\circ }$ 在模拟45°仰角的山区${}^{\circ }$ GNSS 卫星被阻挡的地方。