Anti-cogging apparatus and methods for reducing cogging of rotating shaft

An apparatus that improves rotation of a rotatable shaft, wherein the rotatable shaft has a cyclical cogging torque acting thereon in a first direction, the apparatus comprising:

• a support member that is adjacent the rotatable shaft, wherein the rotatable shaft is operable to rotate relative to the support member;
• a first anti-cogging member;
• a second anti-cogging member that is coupled to the rotatable shaft for rotation with the rotatable shaft;
• a cam surface that is included on the support member or one of the first anti-cogging member and the second anti-cogging member;
• and
• an abutment member that is coupled to the first anti-cogging member or the second anti-cogging member, the abutment member operable to abut against the cam surface to provide an anti-cogging torque to the rotatable shaft in a second direction that opposes the first direction to at least partially offset the cogging torque,
• wherein at least one of
• (i) the first anti-cogging member and the second anti-cogging member are dedicated to providing the anti-cogging torque and do not provide a cogging torque,
• (ii) a frequency of the anti-cogging torque is a same frequency as a frequency of the cogging torque,
• (iii) a phase of the anti-cogging torque is a same phase as a phase of the cogging torque, or
• (iv) a magnitude of the anti-cogging torque is equal and opposite a magnitude of the cogging torque.