Processing a measured vibroacoustic signal for rock type recognition in rotary drilling technology

Rotary drilling technology with diamond bits places high demands on expertise and experience. It plays an important role in the search, preparation, and extraction of raw materials in geological and engineering research. A large amount of hard-to-disintegrate raw materials are currently disintegrated directly by drilling diamond bits. The technology of the disintegration of rocks by rotary drilling represents a significant point and it is a central focus in the field of research in order to optimize the process. Optimization of the process currently considers both the energy and economic aspects, the efficiency of the drilling process, plus the protection of the working environment and the environment. In the case of rotary drilling technology, an interaction between the disintegrating tool and disintegrated rock or rock massif occurs. The interaction of the tool with the rock is a rudimentary source of vibration and noise. The generated vibroacoustic signal is an integrating information source. Information about the current state of the drilling process and the drilling device is obtained indirectly by processing this signal. The basic aim is to use the vibroacoustic signal to identify the type of drilling rock, i.e. its classification to the relevant category from a geomechanical point of view in relation to the optimal drilling mode. This paper deals with the use of a vibroacoustic signal in order to identify the rock in terms of the efficiency of the set mode (i.e., pressure force, revolutions and drilling bit) under current geotechnical conditions. The paper also points to the possibility of recognizing and classifying rock in the drilling process by use of a vector quantization method utilising the vibroacoustic signal. (C) 2018 Elsevier Ltd. All rights reserved.