Using uncertain set points in predictive functional control

Controlling a process variable to an exact set point is not necessary in many technical applications; the aim is rather to reach a defined interval or to avoid another. Finally, it is possible to formulate a fuzzy goal for the requirement to the controlled variable. The fuzziness of the set point allows reducing variations of the manipulated variable. In doing so, the actuator´s durability will increase. In this paper we present an approach to formulate fuzzy set points for the controlled variable and the variation of the manipulated variable. These two fuzzy goals will be applied to calculate a trajectory of optimal set points by using the method of predictive functional control.