Wobble motor


A variable gap electrostatic motor that generates rolling motion of the rotor on eccentric stator without slip.

Wobble motors are also called harmonic electrostatic motors. These motors consist of a rotor, a stator with electrodes for the generation of electrostatic force, and an insulation film on the rotor or stator surface. The rotor rotates in a reverse direction to the revolution. The rotation speed is (the revolution speed) x {(the stator circumference - rotor circumference) / (rotor circumference)}. Characteristics of the wobble motor include 1) the ability to easily provide low speed and high torque when the rotor circumference is very close to the stator circumference, 2) no friction and wear problems because of no sliding parts, 3) the ability to use diverse materials, 4) an easily increasable aspect ratio. On the other hand, the revolution of the rotor can cause unnecessory vibration. Production examples include a wobble motor that supports a rotor by a flexible coupling, and a wobble motor fabricated by the IC process and whose rotor rolls at the fulcrum.


[Related Terms]
Electrostatic motor