There is a need to draw various patterns on the inner wall of a small pipe several millimeters in diameter to develop a precise linear scale. Since the authors have already developed a two-dimensional ultrasonic actuator that can move an object is two orthogonal directions independently, they now offer a rotary linear motor, in which the motor shaft is driven by a pair of two-dimensional ultrasonic actuators. Hence, the motor can rotate and move directly, simultaneously, or independently. Good positioning accuracy was obtained for simultaneous two directional drive by controlling the motor with a proportional control: the steady errors were 1.41° and 0.73 mm in the rotary and linear directions, respectively. However, the positioning accuracy greatly decreased for one-directional drive: the steady errors were 27.5° for rotational motion and 20.3 mm for linear motion. To improve these poor positioning accuracies for the one-directional drive, RC series circuits were connected parallel to the piezoelectric devices of a two-dimensional ultrasonic actuator in order to reduce the interference due to the self-EMF induced by the ultrasonic vibration of one pair of piezoelectric devices on another pair. In addition, proportional control was replaced with proportional and integral control. As the result, the positioning accuracy for one-directional drive has been greatly improved, to 0.05° for rotational motion only and 0.006 mm for linear motion only. © 1998 Scripta Technica, Electron Comm Jpn Pt 3, 82(2): 48–57, 1999