Whether the spreaded good opinion about fuzzy controllers is justified

In the paper, using some MATLAB fuzzy logic toolbox Demos, in which the fuzzy controllers are compared with the classical PID ones, it is shown that the well tuned classical PID are significantly better than those fuzzy presented in the Demos. It is shown, that using fuzzy approach, it is very difficult to shape the inputoutput nonlinearity, describing the so called fuzzy block of the fuzzy controller. It is also shown, that the linear fuzzy block (created to obtain comparable results with the classical PID controllers) is not justified at all, because it may be replaced by the usual summing junction connection, which is significantly simpler. The considerations of the paper do not support the idea of fuzzy controllers.