Sr. no	Point of Difference	Feedback control system	Feed Forward Control system
1	Definition	Systems in which corrective action is taken after disturbances affect the output	Systems in which corrective action is taken before disturbances affect the output
2	Necessary requirement	Not required	Measurable Disturbance or noise
3	Corrective action	Corrective action taken after the disturbance occurs on the output.	Corrective action taken before the actual disturbance occurs on the output.
4	Block Diagram	enter image description here	enter image description here
5	Control Variable adjustment	Variables are adjusted depending on errors.	Variables are adjusted based on prior knowledge and predictions.
6	Example	Use of roll sensor as feedback element in ship stabilization system.	Use of flowmeter as feed forward block in temperature control systems.