Completed notes of the course

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1 19/09/19 INTRODUCTION TO AUTONOMIC CONTROL SYSTEM Control system: collection of interconnected components that can be made to achieve DESIRED RESPONSE in the face of external disturbances. The desired response can act in 2 ways: ➔ regulator (maintain a certain physical quantity within specified limits) ➔ track a specified dynamic trajectory. There are two basic ways in which a control system can be made to operate: 1. OPEN LOOP control system - The controller acts on u. - If x is not 0 you will have oscillation in the output. X ad es can be the external T LIMIT: not able to compensate for disturbances that are not controllable and that are a priori unknown. They can perform satisfactorily as long as the external conditions do not affect the system much. 2. CLOSED LOOP control system FEEDBACK: method for controlling a system by reinserting into it the results of its past performance. 3. - Negative feedback: if the output becomes higher than the controller, the error will be negative, and it slow down the output (and viceversa). Any changes in the system output are compensated for by change in controller action in the opposite direction. The negative feedback is the key attribute that allows closed - loop system to be self-regulatory. In physiology the organism is self-regulating →it self-maintains the HOMEOSTASIS (fixity, stasis) Stasis: complex control action, different from statics. Dynamic system which allow to have a static final condition. (intrinsic working point, adaptive control mechanisms, cross-coupling, hierarchical structure). The feedback appears in the REFLEX in a physiological system. The autonomic nervous system (ANS) is the main player of the homeostasis and it mediates many feedback mechanisms for the physiological control. The ANS is a division of…