EAAI Journal 2026 Journal Article
A lightweight prior-encoding-decoding cascade framework for robust depth completion in robotic grasping of transparent objects using RGB-D sensors
- Ling Tong
- Kun Qian
- Bo Zhou
- Fang Fang
One of the critical steps in robotic sorting is the accurate perception of objects using RGB-D sensors, which enables the generation of precise grasping poses. Sorting transparent objects with industrial robots is challenging due to their low contrast and sparse depth information. Current transparent object perception methods (depth completion) attempt to learn multi-level feature representations from RGB and sparse depth data. However, they neglect the effective interaction of shallow RGB-D features and fail to preserve high-frequency details in deep features. To tackle these issues, we propose a lightweight Prior-Encoding-Decoding (PED) cascade depth completion framework for reconstructing complete depth data from severely sparse depth maps of transparent objects. Specifically, we design a Cross-modal Fine-grained Channel Attention Module (CFCAM) to dynamically integrate shallow RGB-D features, establishing dependencies between local and global features. Additionally, we apply the Haar Wavelet Transform (HWT) during the encoding phase and implement a Nonlinear Activation Upsampling Module (NAUM) in the decoding phase to effectively retain high-frequency details and enhance the richness and integrity of deep feature representations. PED was trained and evaluated on three mainstream datasets: TransCG, ClearGrasp, and Omniverse Object and achieved prediction accuracies of 89. 48 %, 84. 07 %, 80. 47 %, 38. 77 %, and 45. 05 % on five test sets under the 1. 05 threshold metric. Grasping experiments conducted on the UR5 robotic platform further demonstrate that PED achieves a transparent object grasp success rate of 84. 52 % using only a low-cost RGB-D camera. The project is available at: https: //sites. google. com/view/project-ped.