Lissajous Curve-Based Vibrational Orbit Control of a Flexible Vibrational Actuator with a Structural Anisotropy

This paper proposes a novel flexible vibrational actuator with a structural anisotropy and its control method to diversify the vibrational behavior. First, the analytical model of the proposed actuator, which comprises a rectangular cross- sectional flexible beam and a rotational-type motor, is intro- duced. Regarding the structural anisotropy, the rotational axis of the motor is nonparallel to both principal axes of bending stiffness of the beam. Then, the vibrational phenomenon of the actuator is theoretically revealed. It is shown that using the synthetic wave input constituting two sine waves based on the resonance frequencies for the principal axes of the beam, the vibrational orbit of the tip of the beam can be controlled in the same manner as the Lissajous curve. Finally, the pro- posed method is experimentally validated. The Lissajous curve- based vibrational orbit control is performed using a prototype actuator. Furthermore, an application to underactuated-type locomotor is demonstrated.