A device comprising: a first platform (310; 410; 610; 710; 810) having a first side, wherein the first platform is a rotor platform; a second platform (330; 430) having a second side that at least partially overlaps the first side of the first platform, wherein the first side remains within a predetermined distance to the second side in response to rotation of the first platform about an axis of rotation (406; 606; 706; 806) of the first platform, wherein the second platform is a stator platform; a plurality of magnets mounted to the first platform in a circular arrangement around the axis of rotation, wherein the plurality of magnets provides a first-platform magnetic field; a first conductive path forming a first coil extending around the axis of rotation; a second conductive path forming a second coil extending around the axis of rotation, wherein the second coil is interleaved with the first coil, wherein the first and second conductive paths comprise: a first plurality of conductive structures included in the second platform in a substantially coplanar arrangement; a second plurality of conductive structures included in the second platform in a substantially coplanar arrangement that is substantially parallel to the substantially coplanar arrangement of the first plurality of conductive structures; and a plurality of electrical contacts that electrically couple the first plurality of conductive structures to the second plurality of conductive structures; and circuitry that causes a first electrical current to flow through the first electrically conductive path and a second electrical current to flow through the second electrically conductive path, wherein the first and second electrical currents generate a second-platform magnetic field that interacts with the first-platform magnetic field such that the first platform rotates about the axis of rotation. a first platform (310; 410; 610; 710; 810) having a first side, wherein the first platform is a rotor platform; a second platform (330; 430) having a second side that at least partially overlaps the first side of the first platform, wherein the first side remains within a predetermined distance to the second side in response to rotation of the first platform about an axis of rotation (406; 606; 706; 806) of the first platform, wherein the second platform is a stator platform; a plurality of magnets mounted to the first platform in a circular arrangement around the axis of rotation, wherein the plurality of magnets provides a first-platform magnetic field; a first conductive path forming a first coil extending around the axis of rotation; a second conductive path forming a second coil extending around the axis of rotation, wherein the second coil is interleaved with the first coil, wherein the first and second conductive paths comprise: a first plurality of conductive structures included in the second platform in a substantially coplanar arrangement; a second plurality of conductive structures included in the second platform in a substantially coplanar arrangement that is substantially parallel to the substantially coplanar arrangement of the first plurality of conductive structures; and a plurality of electrical contacts that electrically couple the first plurality of conductive structures to the second plurality of conductive structures; and a first plurality of conductive structures included in the second platform in a substantially coplanar arrangement; a second plurality of conductive structures included in the second platform in a substantially coplanar arrangement that is substantially parallel to the substantially coplanar arrangement of the first plurality of conductive structures; and a plurality of electrical contacts that electrically couple the first plurality of conductive structures to the second plurality of conductive structures; and circuitry that causes a first electrical current to flow through the first electrically conductive path and a second electrical current to flow through the second electrically conductive path, wherein the first and second electrical currents generate a second-platform magnetic field that interacts with the first-platform magnetic field such that the first platform rotates about the axis of rotation.