Real-time capable control strategy for hydraulic systems while systematically taking into consideration control (rate) and state variable constraints

A method for operating an actuator of a hydraulic system, the method comprising:

• generating a control variable trajectory for the actuator by:
• supplying a set point to a trajectory planning procedure;
• generating from the supplied set point, a trajectory of constrained input values for a filter integrator chain and a trajectory of flat desired states using the trajectory planning procedure;
• supplying the trajectory of constrained input values and the trajectory of flat desired states to a flatness-based feedforward control procedure;
• and
• generating the control variable trajectory for the actuator from the trajectory of constrained input values and the trajectory of flat desired states with the flatness-based feedforward control procedure,
• operating the actuator to influence an input variable of the hydraulic system based on the generated control variable trajectory,
• wherein at least one constraint is applied to the set point in the trajectory planning procedure to generate the trajectory of constrained input values, and
• wherein the least one constraint is dependent on the trajectory of flat desired states.