Central axis approach for computing n-finger force-closure grasps

In this paper, we propose a new approach for computing force-closure grasps of two-dimensional and three-dimensional objects. Assuming n hard-finger contact with Coulomb friction model and based on central axes of the grasp wrench (i.e., force and torque), we develop a new necessary and sufficient condition for n-finger grasps to achieve force-closure. We demonstrate that a grasp is force-closure if and only if, its wrench can generate any arbitrary central axis. According to this condition, we reformulate the force-closure test as a linear programming problem without computing the convex hull of the primitive contact wrenches. Therefore, we present an efficient algorithm for computing n-finger force-closure grasps. Finally, we have implemented the proposed algorithm and verified its efficiency through some examples.