Simple systems: first-order behaviour

Abstract

Systems behave differently, as do humans. Some people respond quickly to changing information, others take much longer to react. Some people are more extrovert and quickly become overexcited, while others take any change to their life in their stride. If we inject different input signals to systems, we also see that the system behaviour changes — some systems respond quickly, others respond more slowly; some become over-excited and ‘bounce’ around, while others sluggishly follow the input signals. What determines their behaviour is referred to as the ‘dynamics’ of the system. Although the dynamics of many systems are quite complex, we can often approximate complicated system dynamics by simpler representations (which are often quite sufficient for control design).