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Introduction. High-quality ventilation of underground workings is an important condition for safe and accident-free mining. Research on aerological situation control in work areas is ongoing, but the problem of creating reliable adaptive ventilation systems for shafts and mines remains urgent despite the progress made. In course of excavation, the system of workings on the horizon develops a highly complex structure. Auxiliary ventilation is often the only way to achieve high-quality air exchange in the working area. Methods of research. To continuously provide the working area with an estimated amount of fresh air, as well as to intensify ventilation if the concentration of toxic contaminants is increased, mine auxiliary fans (MAF) are used. The best way to improve MAF environmental and economic efficiency is to automatically control the fan capacity. Results and analysis. The program embedded in the programmable logic controller (PLC) provides for comparing the transmitters readings and the aerological situation allowed by the parameters as well as making a decision on changing the fan capacity. If the change is required, the PLC sends an appropriate command to the controller to adjust the fan engine speed. The MAF scheme is simplified if the blind drift is straight because the transmitter is in the line of sight of the receiver and there is no need for a repeater. The UMP design is of a minimal complexity when the mine working is straight and the control task is limited to ensuring constant air flow supplied to the bottom-hole zone. Out of all the data devices, only the flow transmitter remains in the circuit, while the repeater and PLC are excluded. It should also be noted that during the entire period of tunneling, the fan of an unregulated MAF creates an excess power consumption, therefore consuming more electricity than the fan of an intelligent mechatronic module (IMM). Conclusions. Conversion of MAF to IMM will provide the required amount of fresh air to the bottom-hole zone increasing the safety of miners. Real-time control of IMM capacity will significantly reduce energy consumption and create favorable conditions for optimizing ventilation according to the “price-quality” criterion.

Starting properties are the main operational ones, on which the reliability of low-temperature start-up of heat engines of automotive equipment depends. Reciprocating heat engines of internal combustion begin to work stably at a certain, relatively high frequency of crankshaft spinning by a starting device. The article discusses the working process of starting the engine with a direct-on-line electric starter, which is the theoretical basis for designing electric starter start systems for engines of new automotive and tractor equipment. Keywords: storage battery, starter circuit, starter, drive, starting properties, torque resistance, indicator torque, minimum starting frequency. 375199@mail.ru

As the global rich mineral deposits are becoming depleted, the deposit development is performed with a deeper bedding and in much more difficult mining and geological conditions. This circumstance determines both the increase in the labor intensity and development costs, and the increased likelihood of emergencies. In recent years, the accidents have become more frequent at the Russian mining enterprises, aggravated not only by the significant damages, but also by the casualties. The ongoing efforts to correct the tight situation do not have a perceptible effect. A complete exclusion of the presence of people underground should be considered as a drastic remedy for preventing human casualties. It can be achieved only through the use of machinery and technology for manless mining using the automated control systems. The Department of Engineering Mechanics of the Ural State Mining University has formed the concept of a “remote-controlled robotic complex for underground mining”, according to which a surface-controlled system of mining equipment will absolve the miners from working underground. At present, the favorable conditions have been laid for combining the in-mine equipment and permanent installations into a single complex under the control of operators located on the soil surface. In accordance with the concept, the technological robotic complex is transformed into a mechatronic system of the underground mining equipment. The mechatronic system is divided into the separate subsystems by the types of equipment. Particular attention is paid to the automated complex remote-control system based on the telemetry principles using the latest means of data acquisition, conversion and transmission. The system interface provides the most efficient and error-free performance of the operator throughout the entire shift. The concept implementation of the remote-controlled robotic complex in the mining industry will allow not only to avoid the tragic consequences of emergencies in the mines, but also to elevate the national mining equipment and technology to the highest world standards.

Various parameters and characteristics that can be determined by both experimental and computational methods are used to assess the efficiency of fuel use for performing transport work by cars. The article discusses computational methods for studying the influence of design and operational factors on the fuel efficiency of cars with a manual transmission. Keywords: car, mechanical transmission, fuel and economic characteristics, travel fuel consumption, specific effective fuel consumption, fuel consumption equation, control fuel consumption, design and operational factors