A new state feedback control design approach which guarantees the critical realization

State feedback control (SF, defined as a constant gain K on the plant system state x) is by far the best form of control. However the existing design of K always assumes x is fully available. Thus this design ignores the realization of SF control when x is unmeasurable. Hence for most plants, the critical loop transfer function and robustness properties of SF control cannot be realized. This paper presents a simple, complete and systematic design approach whose design of K is bayed on the parameters of the realizing observer and does not assume x is fully available, and which can realize the loop transfer function and robustness properties of its SF control for most plants. This new SF control unifies completely the existing SF control and static output feedback control, and it can still achieve high feedback system performance and robustness for most plants.