A backup assist system for a vehicle reversing a trailer includes an input element, including a base and a rotary element rotatably coupled with the base. The system further includes a controller causing a rotation of the rotary element relative to the base to be constrained in a first rotational movement mode that is biased toward a center position. The controller further interprets a first instantaneous position of the rotary element as a trailer control commanding position and outputs a vehicle steering command based thereon.