This paper studies the problem of passive grasp stability under an external disturbance, that is, the ability of a grasp to resist a disturbance through passive responses at the contacts. To obtain physically consistent results, such a model must account for friction phenomena at each contact; the difficulty is that friction forces depend in non-linear fashion on contact behavior (stick or slip). We develop the first polynomial-time algorithm which either solves such complex equilibrium constraints for two-dimensional grasps, or otherwise concludes that no solution exists. To achieve this, we show that the number of possible `slip states' (where each contact is labeled as either sticking or slipping) that must be considered is polynomial (in fact quadratic) in the number of contacts, and not exponential as previously thought. Our algorithm captures passive response behaviors at each contact, while accounting for constraints on friction forces such as the maximum dissipation principle.
SPARK Hand: Scooping-Pinching Adaptive Robotic Hand with Kempe Mechanism for Vertical Passive Grasp in Environmental Constraints
School of Future Technology, Harbin Institute of Technology（哈尔滨工业大学未来技术学院）；Laboratory of Robotics, X-Institute（X研究所机器人实验室）；Shude College, Southern University of Science and Technology（南方科技大学舍德学院）；Department of Mechanical Engineering, Tsinghua University（清华大学机械工程系）
Intersection-free Robot Manipulation with Soft-Rigid Coupled Incremental Potential Contact
ZenusTech Inc.（泽努斯科技公司）；Shanghai Jiao Tong University（上海交通大学）；SJTU-Yale Joint Center of Biostatistics and Data Science, National Center for Translational Medicine, Shanghai Jiao Tong University（上海交通大学-耶鲁大学生物统计与数据科学联合中心，上海交通大学国家转化医学中心）
