Objects in the real world are often not naturally positioned for functional grasping, which usually requires repositioning and reorientation before they can be grasped, a process known as pre-grasp manipulation. However, effective learning of universal dexterous functional pre-grasp manipulation necessitates precise control over relative position, relative orientation, and contact between the hand and object, while generalizing to diverse dynamic scenarios with varying objects and goal poses. We address the challenge by using teacher-student learning. We propose a novel mutual reward that incentivizes agents to jointly optimize three key criteria. Furthermore, we introduce a pipeline that leverages a mixture-of- experts strategy to learn diverse manipulation policies, followed by a diffusion policy to capture complex action distributions from these experts. Our method achieves a success rate of 72.6% across 30+ object categories encompassing 1400+ objects and 10k+ goal poses. Notably, our method relies solely on object pose information for universal dexterous functional pre- grasp manipulation by using extrinsic dexterity and adjusting from feedback. Additional experiments under noisy object pose observation showcase the robustness of our method and its potential for real-world applications.
Extrinsic Dexterity Usage: Our policy leverages the table and inertia to aid in manipulating objects.
Adaptability: Although our policy failed to pull up the pan initially, it adjusted by lowering the arm on the second attempt, successfully pulling up the pan.
While our method achieves a high success rate across the entire dataset, it still struggles with irregularly shaped objects, particularly thin and slender ones like knives and pens.