Systems comprising an input device configured to output a variable control signal, a controller configured to receive the variable control signal and derive a torque command in accordance with the variable control signal, and a freight conveying device comprising a motor configured to receive the torque command and produce an output torque on a motor shaft in accordance with the torque command are disclosed. Also methods comprising receiving, at a controller, a variable control signal from an input device, deriving, by the controller, a torque command in accordance with the variable control signal, and driving, by the controller, a motor of a freight conveying device in accordance with the torque command are disclosed.