“How can control the rate of change of our control system?”
Proportional control systems are great for correcting the error of simple applications. However, one major drawback is that this method does not control the rate of change of the control system. For example, let’s say that we have a self-driving car that needs to accelerate to the speed limit of a roadway. Proportional Control might accelerate so fast that it actually overshoots the speed limit and causes an accident! To solve this, we can introduce a factor called a derivative control which modulates the rate of change of the system. If we were to introduce it to the self-driving car, then its rate of change would be held in a sustainable manner and decrease to zero as it becomes closer to the setpoint.