3DC-Cobotic Manipulator

Abstract

The 3DC-Cobotic Manipulator is a passive robot designed for direct collaboration with a human operator. This Cobot utilizes three wheel CVTs to control the rotational axis of a sphere. The sphere’s motion is then transmitted to linear motions in Cartesian space via a serial manipulator. Design and construction of the Cobot prototype is described in detail. The kinematics of the 3DC-Cobotic Manipulator is divided into five spaces: configuration space, joint space, spherical space, coupling space, and steering space. The transformations of these spaces are provided, and simulation motion was performed to verify the overall kinematics of the Cobot. The Control structure of the Cobot consists of feedforward and feedback controls. We performed two path experiments using this controller. In the first experiment, an operator moved the end-effector along a vertical straight line. Then in the second experiment the operator moved the end-effector back and forth along a circular reference path. The experimental results show the controller can reduce error, and achieve satisfactory track reference paths.

Keywords: Cobot, Kinematics, Passive