Measurement of cutting tool wear is critical in metal cutting operations. In automated manufacturing, sensing of tool wear is of interest. In single point cutting tools, wear parameters are expressed in terms of wear land width and crater depth, which may not be the ideal or effective parameters to explain the wear related phenomenon in metal cutting. This paper deals with the measurement of wear by considering the three dimensional nature of the wear phenomenon. For this a special relocating fixture was designed and realized and the land and crater wear profiles were plotted in a single...
The present paper describes the development of the practical system for simulation and representation of the cutting process with milling. The data recording during the cutting process, ensuring reliable identification of the machining process, is effected by means of a measuring system based on the information obtained by means of sensors. The system is based on the knowledge from machines, technological processes, machining and experiments executed. By means of the system for simulation it is possible to forecast the development of events that will take place during the cutting process...
The defects of flexible element (belt) have been modeled in this work. The dependency of bearing housing vibration velocity of dynamic test bench has been got. It is defined that the quantity of defects influences the parameters of the vibration of mechanical system.
Most of the chemical-technological processes are extremely dangerous. Conventional monitoring systems based on stationary gas analyzers do not give information about where medium leaks from. This report describes a new way of constructing automatic system for potentially dangerous medium leakage localization at the actuating production lines. Design concept of automatic leakage’s monitoring and control system with the distributed network structure are considered. The information channel works out at one-chipped base with semiconductor gas-sensitive element. Diminutireness (1 sm³), low power...
The misfire detection plays an essential role for the on-board diagnosis of sparc ignition engines and is prescribed by law in the United States of America since 1989 (OBDII). According to the last revised edition from 1996, the misfire detection rate must equal 100 percent for the 2002 model year under all operating conditions relating to speed and torque. Actual methods for misfire detection in sparc ignition engines base on measuring speed fluctuations. But they don't work reliably even at high speed and low torque. Hence this paper describes a new approach which consists of measuring the...
New method of observation and diagnosis of inverter-fed induction motor drives is developed and tested. Unsymmetrical conditions concerning the machine impedances or valves operation are reflected in the spectrum of the current spacephasor. We estimate the spectrum of the space-phasor with the help of the Wigner- Ville distribution (WVD) and we obtain its time-frequency representation with excellent time and frequency resolution. The proposed method is tested with nonstationary multiple-component signals occurring during the fault operation of inverter-fed drives and transmission lines.
In order to detect short-circuits in low-voltage systems, a system was developed with several digital signal processors. The processors are housed on a DSP board, which is based on the VXIbus, and connected to one another by numerous communications pathways. These communications pathways allow for a high degree of flexibility and scalability. They are used to map the algorithmic structure on to the system. The system includes an interface board, which preprocesses, segments and distributes the data coming from the analogue-digital converters to the DSPs. This board generates a pulse with the...
Controlling of process flow is problematic if the valves do not behave ideally. The non-ideal behaviour of a valve causes the valve position to differ from the action given by the control system, which produces discontinuities in the process flow. This is shown as stick-slip steps in the measurement signals. A curve fitting technique is used in step form detection. In this paper we compare this curve fitting technique to well-known Haar wavelet method and present their ability in reliable step form detection.
The newly developed monitor watches the fluidized condition of FBC (Fluidized Bed Combustor), referring to acoustic signals which are collected by heating tubes in the beds and passing to tube acceleration sensors outside the fluidized Beds. The monitor, without any observation hole or special probes, not only detects the bad-fluidized region, which requires proper operations for preventing from agglomeration, but also diagnoses conditions of the boiler equipment. The monitor adopts the joint time-frequency analysis technique to the acoustic signals as well as considers non-Gaussian...
Abstract:The reliability state of the technical object (system) depend on state of its elements and reliability structure of the system. We consider problem of identification of the technical object state. Problem is formulated as the bayesian classification issue.