Planning and control of robot orientational path

A novel geometric method for the planning and controlling the orientation of a robot´s end-effector as it moves along a prescribed translational path is presented. To eliminate the influence of geometric changes to the path and to be able to predict the orientation, the proposed method plans rotational paths with respect to a natural local coordinate frame formed by three unit vectors, namely, the tangent, normal, and binormal vectors, defined by the geometry of the path. A motion control strategy is developed to maintain the desired rotational speed or acceleration of the end effector. Examples are presented which show the practicality of the method