A trailer backup assist system for a vehicle reversing a trailer, according to one embodiment, includes a sensor that senses a hitch angle between the vehicle and the trailer. The trailer backup assist system may also include a steering input device, such as a rotatable knob, that is movable between a plurality of positions that each provide a desired curvature of the trailer. In addition, the trailer backup assist system may include a controller that determines an offset of the desired curvature when the knob is stationary in a central position. The control then generates a steering command for the vehicle to guide the trailer on the desired curvature, taking into consideration the offset.