Feedback control method and unit of a servo controlled system which affects the psychophysical state of a user

A feedback control unit of a servo controlled system which acts on the environment surrounding a user for adjusting at least one feature of the environment which affects the psychophysical state of the user, the control unit comprising:

• a memory device in which there is stored a desired optimal value or a range of desired optimal values of a psychophysical feedback parameter of the user correlated with the perception that the user has of the feature of the environment adjusted by the servo controlled system;
• an estimation device for cyclically estimating a real value of the psychophysical feedback parameter of the user by means of at least one measurement directly performed on the user;
• and
• a driving device for cyclically driving the servo controlled system for seeking the desired optimal value of the psychophysical feedback parameter;
• the control unit operable:
• to identify at least one physical environmental feedback quantity related to the environment which surrounds the user;
• to determine a desired optimal value or a range of desired optimal values of the physical environmental feedback quantity;
• to cyclically measure a value of the physical environmental feedback quantity by means of a measurement performed in the environment;
• and
• to cyclically drive the servo controlled system to seek both the desired optimal value of the psychophysical feedback parameter and the desired optimal value of the physical environmental feedback quantity using a first control loop, which is based on the physical environmental feedback quantity, and a second control loop, which is based on the psychophysical feedback parameter and corrects the action of the first control loop within a predetermined margin.