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In the operation schemes of optical electronic devices (OED), such as digital autocollimators, direction finders, Shack-Hartmann sensors, as well as astro-orientation systems, projection measuring systems, geometric calibration schemes for OED, the photo-detector acts not only as a receiving device, but also as a measuring device. The tasks facing the OED photo-detectors. The solution to the problem is the use of several photo-detectors installed on one electronic board. Since OED photo-detectors act, inter alia, as measuring devices, it is necessary to perform their geometric calibration. Geometric calibration involves the measurement of interior orientation parameters used in the processing of OED images. Geometric calibration makes it possible to eliminate errors in mutual exposure of photo-detectors on one electronic board installed in the focal plane, as well as distortions introduced by the OED lens, primarily by distortion. The correctness of the interior orientation parameter determination is influenced by the relative position of the collimator, with the help of which the geometric calibration is performed, and the calibrated OED itself, i. e. the external orientation elements. The task is to separate the interior orientation parameters and the elements of external orientation. This is achieved using the method of mathematical processing of measured data in the forward and inverted positions of the collimator. This method of geometric calibration allows to use it for geometric calibration of OED with a large number of photo-detectors. The paper presents the results of the geometric calibration of the interior orientation parameters when the collimator projects a test object onto three photo-detectors of the OED layout. The factors influencing on the accuracy of the geometric calibration of the interior orientation elements for OED are determined in the paper. The developed method for geometric calibration of the interior orientation parameters for multi-matrix OED provides high measurement accuracy – not more than 0.1''–0.2''.

This article presents software tools designed for construction of heterogeneous models by software integration of logical models having their work methods set in the knowledge bases and engineering models created in a technical simulation environment. In order to build logical models we use our software «Software-and-mathematical model of the command-andmeasurement system’s onboard equipment». Engineering models are built in the graphical programming environment of the LabVIEW. The software functions are described for creation of graphical schemes of models, data structures and telemetry data packages design, creation of the command base and setting of the methods of the model’s elements work in the knowledge bases’ rules. We provide an example of a heterogeneous model simulating the logics of the spacecraft’s command-and-measurement system’s onboard equipment operation including the library of virtual devices for the receiving and transmitting path simulation and the knowledge base with the rules of the onboard system’s interaction during reception, transmission, execution and confirmation of commands. This example demonstrates the points of integration of logical simulators and virtual devices. The model allows to assess the parameters of the receiving and transmitting path and the influence of destabling factors on communication line’s quality, simulate generation and transformation of the signal coming from the source of information – ground segment – to the onboard equipment and simulate logical interaction of the systems if the necessary signal level is provided. Each element of the model can be transformed and processed by the subject area’s specialist depending on the specifics of the solved tasks.

This article provides a technique for design and simulation of an active second order band-pass filter with lineal tuning of Q-factor and independent tuning over a wide range of resonant frequency and transfer coefficient. The tunable band-pass RC-filter is required for selective processing of electric signals in radio engineering systems and devices, as well as in in-formation measuring systems, the acoustic and hydro acoustic equipment, including devices for noise and vibration analysis. The band-pass RC-filter is required in equalizers for allocation of useful signals.It is shown that the filter is constructed on the basis of the active second order correcting link with the use of tunable RCcircuit T-bridge. Calculation formulas for filter parameters are received, i.e. resonant frequency, polar Q-factor and transfer coefficient. It is shown that in the filter circuit these parameters can independently be tunable over a wide range. Resonant frequency of the filter is tuned by means of dual variable resistors with the Q-factor and transfer coefficient remaining constant.Polar Q-factor is regulated by change of resistance of the variable resistor with transfer coefficient and resonant frequency remaining constant. The transfer coefficient changes by means of another variable resistor.The conclusions of expressions for the tuned parameters of the suggested circuit of the active band-pass RC-filter confirming the research are provided, as well as the filter frequency characteristics and tunable parameter diagrams. Filter implementation is supported by simulation with the use of MicroCap10 software.

The article presents the results of an interlaboratory experiment evaluating the differences in the results obtained by different methods of measuring of specific power of magnetic losses of sheet specimens of oriented electrical steel. Measurements were carried out both with the installation CICL-2 that implements measurement method using field coils and a standardized method with calculation of field magnitude from the current value in the magnetizing winding, and with the measuring systems with different design of yokes implementing a standardized method. The article analyzes the experimental data obtained in order to assess the comparability of measurement results for systems with different design of the closing yoke.