Air to open, Air to close 일때 reverse 와 direct, valve opening, valve close 그리고 feedback, feedforward가 구분이 안됩니다.

정리한 바로는

feedback control에서 ( 문제 8.5 figure 8.5 (a) 를 예로들면)

Air to open -> valve opening -> flow increase -> liquid level become higher than SP -> using reverse controler -> lowering flow effect (closing the valve)

feedback

Air to close -> valve closing -> flow increase ->liquid level become higher than SP -> using direct controler -> decreasing flow effect(open the valve)

이렇게 정리했는데, 개념자체가 틀린 것 같습니다.

8.5번좀 속시원하게 설명해주십시오.