Abstract: A method and apparatus are provided for providing for controlled oscillation of a tool centerpoint associated with a function element carried by manipulator simultaneously with motion of a workpiece feature relative to a predetermined location. The tool centerpoint describes a predetermined pattern relative to the workpiece feature as a result of the combined motion. Tool centerpoint oscillation occurs in an oscillation path between two extremes determined by pattern parameters defining pattern amplitude measured with respect to a pattern longitudinal axis. The direction of the oscillation path is defined by input signals representing angles measured relative to a rectangular coordinate system used for defining the predetermined location. The rate of tool centerpoint motion is defined by an input signal representing velocity.

Abstract: An apparatus and method are provided for controlling the motion of a point associated with a function element carried by a machine. The motion describes an oscillatory pattern in a selectable plane through a path between two positions defined by input signals. The oscillatory motion pattern defines cyclic excursions about the path. Motion is effected by iteratively interpolating intermediate positions along the path, computing incremental excursion amplitudes associated with the intermediate position displacements, calculating coordinates of the intermediate position excursions and producing machine actuator control signals to move the machine members to advance the point from its position along the pattern to an intermediate position.