Abstract: A drive system for a cycle has an input that receives drive from a pedal. An output rotates to drive a wheel via an electrical machine that provides motor drive. A drive train transmits drive to the output. The drive train includes first and second epicyclic gear sets EP-1, EP-2, which each include a sun gear, a planet carrier, a plurality of planet gears, and an annulus gear. Both annulus gears are connected to the output. Both sun gears are driven by the electrical machine. The first epicyclic gear set transmits drive from its sun gear to its annulus gear with its planet carrier in a fixed position. The second epicyclic gear set transmits drive from a pedal to its annulus gear via its planet carrier. Electrical assistance may be provided when the cyclist is pedalling and not pedalling.

Abstract: There is provided a method of controlling a pedal cycle and a pedal cycle incorporating the same. The pedal cycle has an electro-mechanical drive arrangement including a continuously variable ratio transmission system having an input which is mounted to rotate about the axis and an output connected to rotate with a hub member, the transmission system comprising an epicyclic gear set including a sun gear in mesh with a plurality of planet gears mounted to rotate about respective planet shafts carried by a common carrier, which is mounted to rotate with the input about the axis, the planet gears being in mesh with an annulus gear, which is connected to rotate with the hub member. Only the sun gear may be connected to rotate a rotor of an electrical machine or an additional machine may be provided.

Abstract: There is provided a method of operating a pedal cycle and a pedal cycle incorporating the same. The pedal cycle has an electro-mechanical drive arrangement including a continuously variable ratio transmission system having an input which is mounted to rotate about the axis and an output connected to rotate with a hub member, the transmission system comprising an epicyclic gear set including a sun gear in mesh with a plurality of planet gears mounted to rotate about respective planet shafts carried by a common carrier, which is mounted to rotate with the input about the axis, the planet gears being in mesh with an annulus gear, which is connected to rotate with the hub member. Only the sun gear may be connected to rotate a rotor of an electrical machine or an additional machine may be provided.