Process of quantitative evaluation of validity of rock cutting model

Most of complex technical systems, including the rock cutting process, are very difficult to describe mathematically due to limited human recognition abilities depending on achieved state in natural sciences and technology. A confrontation between the conception (model) and the real system often arises in the investigation of rock cutting process. Identification represents determination of the system based on its input and output in specified system class in a manner to obtain the determined system equivalent to the explored system. In case of rock cutting, the qualities of the model derived from a conventional energy theory of rock cutting are compared to the qualities of non-standard models obtained by scanning of the acoustic signal as an accompanying effect of the surroundings in the rock cutting process by calculated characteristics of the acoustic signal. The paper focuses on optimization using the specific cutting energy and possibility of optimization using the accompanying acoustic signal, namely by one of its characteristics, i.e. volume of total signal M representing the result of the system identification.