METHOD FOR MONITORING UNDER CONDITIONS OF VIBRATION TESTS OF VARIABLE LOADING AND FATIGUE DAMAGE TO THE STRUCTURE OF HELICOPTER-TYPE UNMANNED AERIAL VEHICLES

摘要

FIELD: structures strength testing.;SUBSTANCE: invention relates to the field of strength testing of full-scale structures, in particular to a monitoring method under vibration test conditions. For calibration, strain gauges are mounted on the main structural elements. Vibration transducers are mounted in the center of gravity of the structure. Harmonic linear and angular oscillations with different frequencies and amplitudes are excited through an adapter connecting the flange of the movable arm of an industrial robot with the main rotor shaft hub, and the linear and angular displacements of the structure in its center of gravity are measured according to the readings of vibration transducers and strain gauges. The dependence of the ratios of strain amplitudes to displacement amplitudes on the oscillation frequency is established. During vibration tests in the structure, a given mode of vibration loading is excited and linear and angular displacements in the center of gravity are measured. Using the obtained dependences, the amplitudes of deformations in the main power elements are determined, according to which the fatigue damage is calculated.;EFFECT: increased reliability of determining the loading and fatigue damage of a structure subjected to vibration loads.;1 cl, 2 dwg