Based on the given para, answer the following question. Sensitivity considerations often are important in the design of Control Systems. Because all physical elements have properties that change with environment and age, we cannot always consider the parameters of the Control System to be completely stationary over the entire operating life of the system. For instance, the winding resistance of an electric motor changes as the temperature of the motor rises during operation. Control systems with electric components may not operate normally when first turned on because of the still-changing system parameters during warmup. This phenomenon is sometimes called “morning sickness”. Most duplicating machines have a warmup period during which time operation is blocked out when first turn on. A good Control System should be: (a) Very sensitive to parameter variations (b) Insensitive to parameter variations (c) Insensitive to input commands (d) Sensitive to input commands Which of the above are correct? Correct Answer (b) and (d) Concept: The CONTROL ACTION is the quality of a system that is responsible for activating the system in order to produce the output. One of the important and useful requirements of a good control system is ‘sensitivity.’ A good control system should not allow changes in the output due to an environment or parametric changes, internal and external distribution i.e. it should be insensitive to parameters variations. So, Option (b) is correct. But, at the same time, a control system should be very sensitive to the input command variation. It should respond and give output for every small change in the input. So Option (d) is correct. So, both (b) and (d) are Correct.