TacDexGrasp: Compliant and Robust Dexterous Grasping with Tactile Feedback
This work provides a more robust and compliant dexterous grasping solution for robotic manipulation researchers and practitioners, particularly for unknown objects.
This paper tackles the challenge of distributing forces and preventing rotational slip in multi-fingered grasping of unknown objects. By using tactile feedback and a Second-Order Cone Programming (SOCP)-based controller, the authors maintain grasp stability against both translational and rotational slip without explicit torque modeling or slip detection, demonstrating robustness and compliance across 12 diverse objects.
Multi-fingered hands offer great potential for compliant and robust grasping of unknown objects, yet their high-dimensional force control presents a significant challenge. This work addresses two key problems: (1) distributing forces across multiple contacts to counteract an object's weight, and (2) preventing rotational slip caused by gravitational torque when a grasp is distant from the object's center of mass. We address these challenges via tactile feedback and a Second-Order Cone Programming (SOCP)-based controller, without explicit torque modeling or slip detection. Our key insights are (1) rotational slip inevitably induces translational slip at some contact points for a multi-fingered grasp, and (2) the ratio of tangential to normal force at each contact is an effective early stability indicator. By actively constraining this ratio for each finger below the estimated friction coefficient, our controller maintains grasp stability against both translational and rotational slip. Real-world experiments on 12 diverse objects demonstrate the robustness and compliance of our approach.