Abstract

Lately the physical models of detachable elements have become widespread. Physical models and detachable elements should have identical dimensional and weight parameters, including mechanical and dynamic characteristics. Physical model should measure the real impact of various physical quantities such as temperature, pressure, force, magnetic field, measure and record both parameters of external influences and their derivatives that allow determination the trajectory of detachable element by its constituents such as angular rate and acceleration in three coordinates. The value of the measured parameters should be stored in an indestructible memory even in the case when the physical model breaks through hard usage and large separation and fall accelerations. In this regard, in parallel with the development of physical models the specific control and calibration equipment (CCA) is developed, which is used both during design and production, and during prelaunch control of detachable physical model, reading, decoding, display and interpretation of measurement data. For measuring transducers with balanced inputs the bridge network simulator is proposed so that the output voltage is not created by changing the resistance of one or more arms of the bridge, rather by incorporating serial connection with resistance of one arm of bridge circuit the additional regulated voltage source from a digital-to-analog converter, which will function as test values, that is equivalent to the measure of non-electrical physical quantity. Analytical dependences of simulator output voltage on electromotive force power supply of bridge circuit, output voltage of digital-to-analog converter and all elements of principle diagram, and error equations for each component of the circuit have been achieved. The CPA includes: digital-to-analog converter (16 channels, ± 10 V, 16 bits); analog-to-digital converter NI 9205 (32 channels, ± 0,2 B, ± 1 V, ± 5 V, ± 10 V, 16 bits); measuring channel adapter; personal computer; interface converter; software that enables to put testing voltage for all channels of detachable element (DE), read data from DE memory, find real conversion factors and use them to correct errors, display resulting flight information in the form of graphs and tables. The possibility of filtering to reduce noise impact of different types is proposed. Metrological verification of the CCA is implemented using nanovoltmeter HP 34420A, which has a resolution of decimal places and the AC/DC calibrator N4-7.

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