“…Variable speed ratio (VSR) output refers that two or more motion outputs exist in one motion period, which is a common movement form in the fields of rotating machinery, 1 polishing machinery, 2 packaging machinery, 3 and micromachine. 4–6 In some situations, such as motor acceleration and deceleration control, 7 quadruped robot foot trajectory control, 4 flapping time asymmetry control of bionic insects, 5 6 VSR motions are directly output by controlling the motor speed, wherefore a series of sensors is used to detect the position of the actuator. In more situations, such as continuously variable transmission, 8 noncircular gear emulsion motor, 9 VSR steering gear and wearable robot, the constant angular velocity input of the motor is converted into a VSR output by using of the special VSR mechanisms including cams, noncircular gears, and electromagnetic gears.…”