Alessandro N. Vargas
Almost all of the vehicles produced in the last few years, specially that ones based on spark-ignition combustion engines, use a mechatronic component known in the field as electronic throttle body. This equipment is used to control the amount of air that flows into the combustion chamber. As a result, the electronic throttle device is an essential component to control the power generated by the engine by regulating electronically the aperture of the throttle valve.
The throttle valve has a builted-in plate, usually made by plastic or metal, that moves around a central axis, and the plate's movements are commanded by a DC motor. In fact, the angle of aperture of the throttle valve is driven by the driver's gas pedal, which has a sensor that generates a voltage signal corresponding to the pedal deflection. This mechanism is referred to as drive-by-wire.
The goal is to control the automotive electronic throttle valve. We want controlling the angle of aperture (position) of the throttle valve. The gas pedal or other automotive device generates a reference tracking signal, and the throttle valve must follow it with a suitable performance.
The signal from the gas pedal acts just like a reference for the throttle valve, and the control problem is that of making the position of the throttle valve to follow the reference as accurately as possible. To allow the control, the throttle body has a sensor for measuring the throttle position. The control of this device has been a topic of investigation in the context of deterministic nonlinear systems, specially because it presents nonlinear phenomena such as friction, backlash, and limp-home.