Grasp planning with kinematic constraints

Abstract

This paper presents an algorithm to calculate the fingertip positions, which can enhance the closure property for a n-finger grasp and ensure the kinematic feasibility. The algorithm starts by selecting a set of initial fingertip positions within the workspace of the robotic hand and on the surface of the object. If the currently selected grasp does not form closure, then the origin of the wrench space lies out side of the convex hull of the primitive contact wrenches. In this case the adjacent positions of each grip point can be generated to form a candidate set of grasps and the most promising one will be adopted based on the measure of a grasp from being a form closure. The measure is defined by considering the distance between the convex hull and the origin. The algorithm is executed iteratively until the origin is eventually contained by the convex hull. Finally, we illustrate the efficiency of the proposed algorithm with an implementation of three numerical examples.