Grasping and in-hand manipulation: Geometry and algorithms (Q1974468)

The authors address the problem of grasping and manipulating three-dimensional objects. They describe a reconfigurable gripper that consists of two parallel plates whose distance can be adjusted by a computer-controlled actuator. The bottom plate is a bare plane, but the top plate carries a rectangular grid of actuated pins that can move in discrete increments under computer control. The authors propose to use this gripper to immobilize objects by frictionless contacts with three of the pins and the bottom plate. They also propose to manipulate an object within a grasp by planning a sequence of pin configurations that will bring the object to a desired position and orientation. A detailed analysis of the geometry of the problem is developed. The authors devise algorithms for planning grasping and manipulation, and they provide an analysis of the efficiency of their approach. In a companion paper, the authors describe results of experiments with a prototype of the reconfigurable gripper.