The results of the development of a sensory subsystem of an ophthalmopneumatic gas tonometer designed to measure intraocular pressure, study the anterior ciliary arteries and measure indicators are presented. After identifying the design features of the device, a structural diagram, an electrical diagram of the subsystem was proposed, a three-dimensional model of the device was made, and the technical characteristics of individual elements were considered. Brief conclusions on the work done are given, as well as the prospects for the development of the project.
Keywords: ophthalmopneumovasotonometer, intraocular pressure, pneumatic system, sensors, range finders, video cameras
The paper describes a method for a measuring amplitude-frequency characteristics using a random broadband signal as a test signal. The results of an experimental verification of the proposed method are given, as the hardware implementation of the meter.
Keywords: measuring instrument amplitude-frequency characteristics, identification, Wiener-Hopf equation, discrete fourier transform
The generalized approach of statistical processing of results of fatigue tests of samples on the basis of a choice of numerical characteristics of parameter of static durability, processing of results of fatigue tests with use of methods of mathematical statistics, construction of a fatigue curve according to the linear regression analysis of mechanical characteristics of materials of designs and machines, definition of parameters of function of distribution of a limit of endurance by results of processing of diagrams of step change of loading is offered.
Keywords: Static strength, cyclic strength, reliability, mechanical properties of materials, endurance limit, mathematical statistics, linear regression analysis, method of step change of load, test planning
The article presents the results of the use of additives based on non-stoichiometric compounds Mo and W to improve railway greases LZ-CNII and CIATIM 201. In the course of the work, a comparative analysis of the thermophysical and tribological properties of these lubricants with additives was carried out. It was also established that the introduction of lubricants of this type of additives into the dispersion medium improves the tribological properties without deteriorating the performance parameters of these lubricants.
Keywords: plastic lubricant, LZ-CNII, CIATIM 201, friction, wear resistance, lubricating film, antifriction additive, non-stoichiometric
In today's market economy, a large number of organizations engaged in the provision of services aimed at verification of various measuring instruments, such as water meters, gas meters, electricity meters and others. For such companies, it is of interest to expand the scope of accreditation, which will significantly expand the range of services provided. The article presents the algorithm of the procedure for expanding the scope of accreditation with a description of the main stages.
Keywords: verification of measuring instruments, accreditation scope
The aim of the article is to analyze types of error and exicting methods of analysis for definition random errors of micromechanics gyroscope and sensors, generally. A comparison of different methods of analysis for determining a random errors is conducted: autocorrelation, power spectral density analysis and Allan variation analysis. This material will contribution to making tests for definition random errors of gyroscopic sensor TG-8A designing in Laboratory of Microdevices.
Keywords: mems sensors; mems gyroscope; systematic and random error; noise analysis; autocorrelation method; Allan variation
The aim of the article is to analyze the existing methods for constructing a model of random errors in micromechanical sensors. A comparison of different methods for determining the parameters of a random process model is presented: autocorrelation, power spectral density analysis, time domain analysis, and Allan variation analysis. This direction is also supplemented by considering the effect of sensor errors on the error of inertial navigation systems. In conclusion, the synthesis of forming filters for various random errors in micromechanical sensors and the results of simulation are given.
Keywords: mems gyroscope; noise analysis; stochastic drift; error modelling
The article proposes the use of a table processor to reduce the complexity of applying the probabilistic paper. Based on the written methodology, the measurement results were processed. Further ways of developing the methodology are suggested.
Keywords: metrological assurance, probabilistic paper, normal distribution law, OpenOffice Calc, MS Excel
The article describes in detail such a tool as computer modeling - the concept, its types, the application spectrum and significance. The paper considers the role of computer modelling in the research and analysis of the condition of technical objects on the example of the temperature stabilization system of the cooling element of a thermobox. The construction of a system for stabilizing the thermal mode of a cooling element of a thermobox in the form of a mathematical model is presented, and its numerical analysis is presented in the graphical simulation environment Simulink of the MATLAB software package. According to the study, conclusions were drawn about the importance and effectiveness of computer modelling in the design and evaluation of the behavior of complex systems.
Keywords: computer modelling, mathematical model, experiment, thermobox, electric motor, the Peltier element, temperature, radiator, fan, transients, steady state
The article is devoted to the issues of preparation for the initial and periodic certification of test equipment. The author reveals the reasons for the need for attestation of test equipment in the example of the stand for PSN. Particular attention is paid to the need for writing guidelines for the program and methodology for attestation of test equipment
Keywords: certification, tests, converter, program and technique, train car, test stand
Results of the performed works at calibration of the metal-cutting machine are given in article. The technology of performance of control is considered. The conclusion in which it is noted that laser trackers including the measuring Vintag vehicle produced by Faro firm, possess high efficiency of the solution of problems of calibration is made. Their software has an opportunity to carry out processing of results of measurements and preparation of reports directly on the platform of performance of work and to give results on the place. To provide the accuracy of measurements of the spatial coordinates of 0.005-0.01 mm at distances to 10000-15000 mm. All these characteristics allow to recommend to machine-building enterprises use of such and similar measuring cars for the solution of problems of calibration of metal-cutting machines.
Keywords: Laser trekker, measurements, geometrical parameters, straightforwardness, perpendicularity, metrology, calibration, metrological characteristics
in work development of the measuring device for assessment of parameters of a deviation of a form of details of cars in cross section is considered. In a basis of this device the principle of contactless measurement, and also a possibility of an exception of errors of installation of details is underlain
Keywords: device, contactless measurements, otskloyeny forms
The article compares the S- and SD-methods of sifting IMF. Was considered an example with a test signal and analysed the effectiveness of decomposition.
Keywords: empirical mode decomposition, error of decomposition, intrinsic mode functions, S-method, SD-method, normalized squared difference, operation of sifting, LabView, Hilbert-Huang transform
Device of torque measurement of rotating shafts of different technical systems is presented in this article. Device was maiden by digital radio channel. Methods of device calibration are described. Examples of measurements of different mechanisms shafts are presented.
Keywords: tenzometric torque, digital radio channel.