GES-UniGrasp: A Two-Stage Dexterous Grasping Strategy With Geometry-Based Expert Selection

Abstract: Robust and human-like dexterous grasping of general objects is a critical capability for advancing intelligent robotic manipulation in real-world scenarios. However, existing reinforcement learning methods guided by grasp priors often result in unnatural behaviors. In this work, we present \textit{ContactGrasp}, a robotic dexterous pre-grasp and grasp dataset that explicitly accounts for task-relevant wrist orientation and thumb-index pinching coordination. The dataset covers 773 objects in 82 categories, providing a rich foundation for training human-like grasp strategies. Building upon this dataset, we perform geometry-based clustering to group objects by shape, enabling a two-stage Geometry-based Expert Selection (GES) framework that selects among specialized experts for grasping diverse object geometries, thereby enhancing adaptability to diverse shapes and generalization across categories. Our approach demonstrates natural grasp postures and achieves high success rates of 99.4\% and 96.3\% on the train and test sets, respectively, showcasing strong generalization and high-quality grasp execution.