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Measurement Techniques, Vol. 58, No. 8, November, 20150543-1972/15/5808-0839 ©2015 Springer Science+Business Media New York839STANKIN Moscow State Technological University, Moscow, Russia; e-mail: porvatov_artur@mail.ru. Translated from Izmeritel’naya Tekhnika, No. 8, pp. 5–9, August, 2015. Original article submitted May 27, 2015.INFORMATION-MEASUREMENT AND CONTROL SYSTEMS FOR FORCE AND VIBROACOUSTIC PARAMETERSM. P. Kozochkin, A. R. Maslov, and A. N. Porvatov UDC 621.9.08:62.503.57Problems relating to the creation of information-measurement and control systems based on monitoring acoustic emission and electromagnetic effects are discussed. Experimental data are presented on the prospects for and limits on the use of these effects for high-speed machining of structural materials.Keywords: adaptive control, technological process, high-speed machining, cutting process diagnostics, information-measurement system, CNC. Automatic maintenance of machine tool equipment with minimal operator interference is impossible without exten-sive use of inbuilt means of measurement [1–3] which gather and process information on the quality of the technological process and work as part of a diagnostic system. The functions of operational diagnostics include evaluating the state of mechanisms and the work process, as well as determining the location and causes of breakdowns, but also making decisions on the liquidation of the consequences of failures. The choice of equipment (probes) for operational diagnostics of a cutting process depends mainly on the following factors [4]: informativeness adequate to the situation in the cutting zone, as well as simplicity and reliability of installation on a machine. At present, the most widespread diagnostic systems are those based on information-measurement systems for force and vibroacoustic (VA) parameters. The devices for measuring force during cutting can be divided into two classes: those that are electromechanical (dynamometers) and those based on electromagnetic effects in an electrical drive (current and voltage sensors). Measurement devices employing electromagnetic effects in an electrical drive with the aid of current and voltage sensors are substantially cheaper and easier to use, so they are widely used in industry for setting up so-called adaptive control [5]. Vibroacoustic signals during cutting and abrasion have a complicated structure that differs from that of the forces that appear during cutting. For example, when the contact area increases during abrasion, the amplitude of the oscillations may increase sharply in some stages, and decrease or not change at all during other stages [6]. A correct evaluation of the state of the cutting process is diffi cult owing to the complexity of the process, for which there is no unifi ed theory, and the structure of its dynamics [7]. There is reason to state that the process of cutting materials is self-oscillatory [6, 8]. Questions of diagnostics of the most important components of the technological equipment responsible for the machining accuracy also arise. Damage to these components during operation can lead to hazardous situations or breakdown of the technological cycle [9–11]. The development of instrumentation and computational techniques in recent years has enabled partial monitoring and diagnostics by means of systems for monitoring machines and equipment based on information technology [5]. Most adaptive control and monitoring systems on the market today react to a change in the cutting conditions through electromagnetic signals from the force part of an electrical drive and automatically adjust the feed to the maximum allowable level for each operation [12]. When necessary, these systems stop the machine because of overload or detected tool failure. The leading manufacturers of computer numerically controlled (CNC) systems, such as Siemens, Heidenhain DOI 10.1007/s11018-015-0804-1