Everybody has been a part of a control system at some time. Some examples of this are when driving a car, balancing a broomstick on a hand, walking or standing up without falling, taking a glass to drink water, and so on. These control systems, however,arenotautomaticcontrolsystems,asapersonisrequiredtoperformarole in it. To explain this idea, in this section some more technical examples of control systems are described in which a person performs a rol