CONTROLLER AND CONTROL METHOD FOR A RIDER-ASSISTANCE SYSTEM ON A STRADDLE-TYPE VEHICLE

The present invention obtains a controller and a control method capable of hastening identification of an object or an event to be focused by a rider of a straddle-type vehicle, the rider having perceived haptic motion.A controller (51) for a rider-assistance system (50) mounted to a straddle-type vehicle (100) includes: a determination section that determines necessity of a warning given to the rider; and a haptic motion performing section that performs haptic motion at least once to reduce or increase acceleration/deceleration of the straddle-type vehicle (100) only for a moment. The haptic motion performing section changes a priority of each wheel (3, 4) at the time of changing a braking force to reduce or increase the acceleration/deceleration only for the moment in the haptic motion according to a focusing direction that is a direction in which the rider should focus by the warning.