Adaptive control of drilling by identifying parameters of object model under nonstationarity conditions

Abstract

The research is intended to investigate and synthesize adaptive control over drilling by identifying parameters of an object model under non-stationarity conditions. Methods. Under conditions of rapidly changing borehole drilling indices, a two-level adaptive control strategy is applied, combining investigation of drilling and its control. The structure of the control system includes an additional block of forming the model on the basis of data on indirect features. Findings. The research develops a method for seeking the extremum developed for the object whose dynamics is described by a first-order linear differential equation. The method allows to determine the value of the output signal by evaluating the initial phase of the transient process caused by the changed input signal for a set step. Originality. The suggested algorithm of noise-free identification makes it possible to assess the factor of the control object transfer under the action of random disturbances. The data obtained is used to adjust the gain factor of the controller in the closed loop automatic control system of drilling. Practical implications. The suggested structure and algorithm of drilling control allow enhancing drilling efficiency by ensuring relevant mechanical drilling rates through defining corresponding rotation speeds and axial loads of a drilling tool.

Development of resource-saving technology when mining ore bodies by blocks under rock pressure

“…Analysis of formula (8) enables concluding that: -when pressure in the upper part of the mining block decreases, after caving the crown, movement of rock mass is observed in both directions (according to the research into breaking ore in the compressed environment) [21,26,40]. That is, not only caved ore but also caved rocks will be compacted; -when pressure in the upper part of the mining block increases, after caving the crown, rock mass will move towards areas with lower rock pressure [36][37][38][39][40].…”

“…To increase iron content in the muck, it is suggested to concentrate the mass at surface crushing and sizing plants. [16][17][18]. It should be considered that in terms of mineralogical composition there are 6-9 varieties of ore, each requiring special treatment.…”

“…from 56% to 62%) [19][20][21]. This updating trend is based on force impacts on the substance during disintegration in the activator but it does not consider processes connected with underground mining of the useful mineral [22][23][24][25]. Constantly improved software of the automated complexes indicates iron content in real time and is able to split ore mass flows by quality.…”

“…When implementing this technology at underground mines of Kryvyi Rih iron ore basin, labour conditions deteriorate and costs for maintaining workings grow because of complicated mining and technical conditions [33][34][35][36].…”

“…To reduce costs for maintaining main openings, mines implement modern methods of monitoring the rock massif state while disturbing it by underground operations [37][38][39].…”