Design and Implementation of a Low Cost Multi-Fingered Robotic Hand Using a Method of Blocks

The control of a mechanical robotic hand is plagued by an inability to derive accurate dynamic models of such a mechanism. The aspects of static and kinetic friction are major obstacles in the control of a mechanical hand. This paper presents a fuzzy-like based controller and its implementation for a low cost robotic hand. The controller has the ability to automatically regenerate the member set during the translation of any arbitrary joint in a robotic hand. A series of simulations has been conducted that illustrate the effectiveness of this controller for providing smooth translation independent of frictional forces.The implementation of the controller used here is based on an IBM compatible computer using a custom designed acquisition/conversion interface and a mechanical hand assembly. A hand with a progressively linked finger structure has been used for simplicity. The acquisition system used here allows bidirectional communication with the sensors and actuators of the hand.A series of experiments have been conducted which verify that the method of blocks was successful for controlling joint position. The simulation results include both fine movements, needed for dexterity, and gross movements that can be used for grasping. This robotic hand produces good results in a low cost implementation.