Application Potential of Express Diagnostics Package (Exsys, IMDC-2) for Diesel Locomotive Engines

The paper reveals aspects of application of the hardware and software package developed by the author for express diagnostics of internal combustion engines.The objective of the research was to develop algorithms, hardware and software framework for system diagnostics of diesel engines as a comprehensive methodology aimed at localising faults in the best way.Research methods included mathematical modelling for building the algorithm of the expert system; methods of observation and experiment used in the design work and improvement of the developed hardware and software package.The use of on-line diagnostics methods is the main factor for the transition to a more efficient condition-based maintenance system, which makes it possible to prevent sudden failures due to diagnostics made during the simplest types of maintenance, as well as to avoid dismantling of nodes with a resource sufficient for further operation. On-line diagnostic methods are divided into organoleptic and indicator ones and belong to the first two levels of system diagnostics as a practical methodology and scientific discipline.Organoleptic data are based on human perception organs and can be formalised using the Exsys expert system developed by the author based on open databases on correlation of faults with their symptoms, which makes it possible to localise the fault in an interactive mode based on the totality of observed external features, such as smoky exhaust of a certain colour, unstable idling, etc.The second development, which is the IMDC-2 package, refers to indicator methods, representing a subclass of dynamic diagnostics. The package consists of an analog-to-digital converter with a shaft speed sensor mounted on the engine and a computer program that interprets the received data. IMDC-2 allows determining the engine power, building acceleration / coasting retardation curves, and obtaining several other characteristics important for diagnostics, for example, the dependence of the angular acceleration of free acceleration of the engine on the frequency of rotation of its shaft. Both developments can be fully applied after minor modification to diesel locomotive engines, which will increase the accuracy of fault detection and reduce the time for their localisation.