What type of control strategy maintains the output variable at the setpoint?

Feedback control is the strategy designed specifically to maintain the output variable at the setpoint. In this method, the system continuously monitors the output and compares it to the desired setpoint. If there is any deviation, the control system adjusts the input to bring the output back to the desired level.

This process involves real-time data collection and automatic adjustments based on the difference (error) between the measured output and the setpoint. By effectively responding to changes, disturbances, or errors in the system, feedback control ensures that the output remains as close to the setpoint as possible over time.

Open-loop control, on the other hand, does not provide any output monitoring or adjustments based on feedback, which means it cannot correct for disturbances. Feedforward control anticipates disturbances and makes adjustments before they affect the output but does not maintain the output at the setpoint directly through corrections based on actual output measurements. Adaptive control adjusts itself in response to changes in the process dynamics over time but also does not directly control the output to the setpoint in the same closed-loop manner as feedback control.