What is a negative feedback?

Although the term "negative feedback" is not known to all, the process behind it, everyone faces daily.One can cite many examples.And, interestingly, the negative feedback is not confined to living organisms, but also for the many technical resources.In part, only because of the progress it exists in the form to which we are accustomed.

principle of feedback is studied in various fields of science.For example, music can use the feedback (feedback), some very famous rock artists such as Kurt Cobain, Ray Link and so on. It is taught in biology, mechanics, electrical engineering, electronics ... in fact, everywhere.Accordingly, in the global network, you can easily find many different answers to the question "what is the negative feedback", but often the answers themselves further generate new questions.All this despite the fact that the purpose of feedback is extremely easy.

What is a negative feedback?Here are a few examples of life.Imagine a person walking on the slippery surface.So he takes one st

ep, then another, and another ... and then the leg starts to slide, the center of gravity of the body gradually (it just seems that instantly) shifts - there is a real danger of falling.At this point, certain muscle groups are reduced, trying in some way to compensate for the unstable state.This deviation can be backward or vice versa, some of the steps in a tilted forward housing.However, in this case, we describe only the external manifestations.The internal mechanism is the following:

  • foot becomes the surface.At this point of her brain sent signals indicating the strength (each, do not hesitate to determine the basis of soft or hard), roughness, slope;
  • in accordance with the received data is corrected body position and placement of the feet;
  • but his leg began to slide.The threat of sustainability.The more intense the slip, the more searches and implementation of optimal method capable of preventing the fall.

Positive feedback used by the skier, which further tilts the body, increasing the speed of sliding.In turn, the negative association opposes the causes of changes in the system.

fact, many gamers are known rudder feedback.That she is!The stronger the player turns the steering wheel to the side, the more opposition from the domestic motor he feels.In this example, there is a current feedback.

Schematically it looks like this: input - system - output.Any changes to the input data and the appropriate change of the output.Recently, with the thus affect the system to return to its original stable state.

Feedback amplifiers can solve several problems at once: to ensure the stability of the gain regardless of the input signal, making the entire system is fully automatic (setting the feedback is carried out only at the initial stage).However, a negative feedback in electronics is not always realized that simple.The special feature is that the feedback signal entering the system should manage actuate compensatory mechanisms before the input data is re-changed.In other words, the speed of feedback should be less than the rate of change of the input signal.Therefore, the scheme based on the high frequencies, there are a number of difficulties.One solution - sync frequency input and feedback.