A system-specific feedback control theory for fluid process control and for motion control has been developed to enable analytical tuning. The system-specific theory enables the determination of the coefficients required to implement (i.e., tune) a proportional-integral (PI) control system analytically from physical characteristics of the fluid or motion system. PI control is essentially PID control with the derivative (D) coefficient set equal to zero. (A derivative coefficient is not essential and may have a detrimental effect on system response characteristics.) System-specific theory, based on the fundamental algorithm for PID control systems, was developed from a "back-to-basics" perspective considering digital, not analog, control of fluid systems and motion systems independently. ControlProblems is an application containing numerical system models corresponding to the problems presented in Chapters 23 though 27 of this book. The problems represent typical systems that may be...