an elastic wave actuator and method to convert electrical energy to mechanical energy with alternate high speed or high torque output options . the actuator comprises a cylindrical rotor flexible shell rotatably mounted coaxially within a stator . a radially disposed series of electromagnetic poles in the stator is energized to generate a rotating electromagnetic field that attracts and deforms the flexible shell to engage the frictional surface of the stator at points of contact that progress around the stator . the circumference of the flexible shell being different from the circumference of the inner stator surface , the rotor rotates at a rate proportionate to the difference between the shell and stator circumferences and much slower than the electromagnetic field . an output shaft coupled to the rotor flexible shell will provide high torque low speed power output . alternately , an elliptical cam and cam output shaft mounted coaxially within the rotor flexible shell provides a high speed low torque power output .