The Problem of Choice Between Measurement Techniques

The assessment of the current conditions of any technical object is based on measurement. Thus, choosing the qualitative descriptor of the object that is to be assessed represents a relatively complex task. This is related both to the informative value of the qualitative descriptor and to the need for applying one or another measurement technique. There are three different ways to deal with the designated task. One possibility is to fix the required level of informative value and choose the measurement technique based on criteria such as the least money expenses for measuring, the shortest measurement duration and the specialization level of the measurement instruments. The second option is to choose specific measurement techniques and obtain the most complete information possible. The third possibility consists in a compromise between the information content of the descriptor and the overall expenses for measurement techniques. By convention, the first option is applied while facing this task, in which the information on the technical conditions of the object is obtained choosing adequate measurement techniques. Determining the value of the structural parameter of the technical conditions is not always possible. The diagnostic parameter, in its turn, is determined by the structural parameters only at a certain level of probability. The producers of machinery are constantly improving their products, upgrading the design of mating parts, changing the properties of wearing surfaces and introducing new materials. As a result, the aforementioned interrelations between the structural and diagnostic parameters are significantly redetermined, whereas the previously engineered diagnostic devices and the implemented methods lead to the ambiguity of the diagnostics. The areas of such ambiguity are here taken into account using a compression vacuum method in order to determine the technical conditions of the sleeve assembly of an internal combustion engine.