Excavator 3D pose estimation from point cloud with self-supervised deep learning

Pose estimation of excavators is a fundamental yet challenging task with significant implications for intelligent construction. Traditional methods based on cameras or sensors are often limited by their ability to perceive spatial structures. To address this, 3D light detection and ranging has emerged as a promising paradigm for excavator pose estimation. However, these methods face significant challenges: (1) accurate 3D pose annotations are labor-intensive and costly, and (2) excavators exhibit complex kinematics and geometric structures, further complicating pose estimation. In this study, a novel framework is proposed for full-body excavator pose estimation directly from 3D point clouds, without relying on manual 3D annotations. The excavator pose is parameterized using pose parameters of geometric primitives under kinematic constraints. A unified deep network is designed to predict pose parameters from point clouds. The network is initially pre-trained on synthetic data to provide parameter initialization and then fine-tuned using real-world data. To facilitate label-free training, the self-supervised loss functions are designed by exploiting the geometric and kinematic consistency between point clouds and excavators. Experimental results on real-world construction sites demonstrate the effectiveness and robustness of the proposed method, achieving an average pose estimation accuracy of 0.26 m. The method also exhibits promising performance across various excavator operational scenarios, highlighting its potential for real-world applications.