Automatic gear-shifting device

A method for shifting gears comprising:

• turning a first rotational rotor of a first motor alternatively clockwise and counter-clockwise successively such that, wherein the first motor creates an oscillatory wobbling action as the first rotational rotor turns, wherein the first rotational rotor rotates a compound planetary transmission, the compound planetary transmission comprising a transmission ring attached to a first ring gear and a drum;
• turning a second rotational rotor of a second motor either clockwise or counter-clockwise, wherein the second rotational rotor rotates a pinion gear of a shift assembly, the shift assembly further comprising the drum and a cap;
• wherein the drum locks with the pinion gear such that the drum rotates as the pinion gear rotates;
• wherein the rotating drum causes the transmission ring to move laterally;
• and
• wherein the first ring gear alternately locks and unlocks with the cap as the first motor wobbles, wherein the wobbling action of the first motor enables the locking.