A magnetic cycloid gear assembly comprising: an outer magnet drum comprising a plurality of outer drum magnets having a first number of magnetic pole pairs, wherein the outer magnet drum has an outer magnet drum axis (As); a first inner magnet drum comprising a first plurality of inner drum magnets having a second number of magnetic pole pairs, wherein the first inner magnet drum has a first inner magnet drum axis (Ar) that is offset from the outer magnet drum axis (As); a second inner magnet drum comprising a second plurality of inner drum magnets having a third number of magnetic pole pairs, wherein the second inner magnet drum has a second inner magnet drum axis (Ar) that is offset from the outer magnet drum axis, wherein the outer magnet drum surrounds the inner magnet drums ; and a plurality of drive mechanisms , each drive mechanism being operatively coupled to each of the first and second inner magnet drums , the plurality of drive mechanisms being configured to drive each of the first and second inner magnet drums to revolve in an eccentric manner about the outer magnet drum axis (As), wherein the first and second inner magnet drums are positioned to offset each other's eccentric motion and are positioned 180 degrees apart from each other about the outer magnet drum axis (As), and wherein the first and second inner magnet drums are positioned apart from each other in the axial direction, each one of the inner magnet drums being positioned closer to opposite axial sides of the magnetic cycloid gear assembly , and wherein the outer magnet drum is configured to rotate about the outer magnet drum axis (As) in response to revolution of the first and second inner magnet drums . an outer magnet drum comprising a plurality of outer drum magnets having a first number of magnetic pole pairs, wherein the outer magnet drum has an outer magnet drum axis (As); a first inner magnet drum comprising a first plurality of inner drum magnets having a second number of magnetic pole pairs, wherein the first inner magnet drum has a first inner magnet drum axis (Ar) that is offset from the outer magnet drum axis (As); a second inner magnet drum comprising a second plurality of inner drum magnets having a third number of magnetic pole pairs, wherein the second inner magnet drum has a second inner magnet drum axis (Ar) that is offset from the outer magnet drum axis, wherein the outer magnet drum surrounds the inner magnet drums ; and a plurality of drive mechanisms , each drive mechanism being operatively coupled to each of the first and second inner magnet drums , the plurality of drive mechanisms being configured to drive each of the first and second inner magnet drums to revolve in an eccentric manner about the outer magnet drum axis (As), wherein the first and second inner magnet drums are positioned to offset each other's eccentric motion and are positioned 180 degrees apart from each other about the outer magnet drum axis (As), and wherein the first and second inner magnet drums are positioned apart from each other in the axial direction, each one of the inner magnet drums being positioned closer to opposite axial sides of the magnetic cycloid gear assembly , and wherein the outer magnet drum is configured to rotate about the outer magnet drum axis (As) in response to revolution of the first and second inner magnet drums . <EOS>