Feedback control has deep roots.
These roots extend as far back as the 3 rd Century B.C. when Ktesibios of Alexandria, Egypt, developed a float regulator that maintained a constant water level in one of the earliest water clocks. Twenty centuries later, feedback control played an important role during the first Industrial Revolution when James Watt's flyball governor was used to regulate the steam engine. Today, the control technology being studied at CSL and elsewhere continues to play a vital role in our everyday lives, with an endless list of diverse applications. Briefly, feedback control is the construction of decisions or actions based on the continuing observation of the outcomes of those decisions. It enables devices and systems to achieve stable, accurate, and robust performance in uncertain environments.