Design of two-wheeled ultrasonic wheel is proposed for applications in micro-stepping displacement devices. The ultrasonic wheel includes a beam and two displacement members which are respectively pivoted on the beam. Two displacement members are not rotatable. In addition, each displacement member includes a wheel sheet and a piezoelectricity element embedded on its surface. When the piezoelectricity element generates and transmits power to the wheel sheet, the wheel induces vibration and deformation. Therefore, due to the wheel sheets and the touched ground involving their relative motion, the displacement device can move and orient its motion direction in a micro manner. The two-wheeled ultrasonic wheel driven by two piezoelectric elements is direct 
movement, no rotor requirement. In this research, a 3-D mechanical element with an extra electrical degree of freedom is employed to simulate the dynamic vibration modes of the linear piezoelectric, mechanical and piezoelectric-mechanic behaviours of the two wheeled ultrasonic wheel.