Means of providing dynamic range of the measuring channel
Abstract
The article considers the possibility of expanding the dynamic range of the measuring channel, in which the primary transducer is a piezoelectric accelerometer, which measures the acceleration during dynamic (shock) tests of various samples of equipment. Impact tests are often performed in conditions of difficult reproducibility of experimental conditions, for example, measurement of shocks and vibrations in pyrotechnic explosions, tests of special purpose onboard systems for endurance, ability to withstand destruction, etc., where due to the transient nature of measurement processes, the attenuators of the automatic selection of the measurement range do not have time to switch when the input signal exceeds the normalized value, or these switches lead, as a consequence, to circuit breaks, to distortion of the measured signal. Therefore, the use of attenuators in such cases is impractical. Thus, the required value of the dynamic range of the measuring channel must be provided exclusively by circuit solutions. The second factor that needs to ensure the acceleration measurement process is the signal-to-noise ratio. Given that when measuring shock effects, piezoelectric accelerometers (generating charge) with a sensitivity of up to 10 pK/ms2 are chosen to ensure the dynamic range of acceleration, the presence of broadband noise will significantly distort the measured signal. This will be especially reflected at low levels of acceleration amplitude, during the attenuation of the shock pulse and the emergence of transients that require research. Also large electromagnetic, vibration, temperature impacts influence measuring devices and the equipment from the environment as the specified tests, in most cases, are carried out not in laboratory conditions, and on specialized landfills. Therefore, the design and development of measuring instruments to ensure these tests is of great importance and relevance
Keywords
acceleration; piezoelectric accelerometer; analog-to-digital converter; signal-tonoise ratio; dynamic tests
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