Noises and disturbances
The observation of systems is disturbed by noises of various origins. These include noises influencing the measurements, inaccuracies, external effects on system operation, as well as fluctuations, connection disorders and side effects in the mechanisms of the system.
Such noises must be filtered out from the observation partly with filtering devices, such as noise filters and damping devices, and partly with computation instruments, such as Big Data methods.
When controlling systems, it is very important to eliminate the effect of disturbances to the fullest possible extent. The control system must be designed so that it filters out disturbance effects at system outputs as much as possible.