Differential Amplifier or Summing Amplifier are usually used in a closed loop control system.
The error signal will be the DIFFERENCE between the setpoint value and feedback value for Differential Amplifier. Whereas for Summing Amplifier, the error signal will be the difference between the setpoint value and feedback value only if one of the value is inverted in polarity.
Another reason Op Amp is used: amplify the error signal as error signals are usually very small.
Hope this helps.
closed loop system
A Closed loop system basically will have a feedback which enables the rectification of the error in the main process,whereas it is not possible in an open loop system
The closed loop control refers to a system whereby an input forcing function is usually determined in part by the system response.
Yes it is
yes
stability and repeatability
Open loop (single cycle) involves a break requiring a restart, easily adapted to closed loop.
The Nyquist stability criterion, named after Harry Nyquist, provides a simple test for stability of a closed-loop control system by examining the open-loop system's Nyquist plot. Under many circumstances, stability of the closed-loop control system may be determined directly by computing the poles of the closed-loop transfer function. In contrast, the Nyquist stability criterion allows stability to be determined without computing the closed-loop poles
Closed loop control systems tend to oscillate due to instability in the system caused by the presence of excessive gain or phase lag. When the gain or phase lag is too high, it can result in the system becoming over-compensated, leading to oscillations as the system tries to correct itself. Tuning the system parameters, such as gain and phase, is essential to prevent oscillations in a closed loop control system.
A cruise control is an example of a closed loop servo.
A control system that appears to be self-regulating. Closed-loop systems employ feedback and a reference of correctness (norm or set point). Deviations from the norm are detected and corrections made in order to maintain a desired state in the system. Closed loop systems provide the homeostatic mechanism of many physiological functions (see negative-feedback) and also control some movement patterns, where feedback from proprioceptors and other receptors play an important part. Compare open-loop-system.
open (in terms of thermo chemistry) ! It cannot be proved with science yet! BUT WHEN ONE TOUCHES SOMEONE, LOOKS THEM IN THE EYE, so forth one feels the exchange of energy(emotions). they are being effected by the surrounding !