Method of operating a pedal cycle having an electro-mechanical drive arrangement

A method of operating a pedal cycle, the pedal cycle having an electro-mechanical drive arrangement including a continuously variable ratio transmission system having an input which is mounted to rotate about an 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 being connected to rotate a rotor of an electrical machine, the electrical connections of the stator of the electrical machine being connected to a controller;

• and a one-way clutch comprising a drive member which is constituted by the common carrier, and a driven member which is connected to rotate with the hub member, wherein the one-way clutch being arranged to connect the hub member to rotate with the carrier when the carrier rotates faster than the hub member;
• the method including the step of:
• applying a time division multiplexed control algorithm to the electrical machine, wherein the time division multiplexed control algorithm alternates between a first control mode in which current generated by the electrical machine is monitored to infer torque applied to crank arms of the pedal cycle and a second control mode in which the current in the electrical machine is controlled using the inferred torque.