Palennyy Y. Improvement of the method of contactless measurement by a magnetic sensor of vibrational displacements of rotating objects

The thesis is devoted to the improvement and introduction of the method of non-contact measurement of the vibration parameters of a rotating boring tool and similar objects of measurement for research purposes. The sources are determined and the indices of vibration characteristics to be investigated are analyzed. The parameters and ranges of vibration measurements have been determined to solve the task. The existing methods and means of measuring equipment used to solve similar problems are analyzed and the requirements to the method and means of measuring technology necessary for solving the task are determined. The analysis of the interaction of the measuring instrument with the object of measurement is carried out and the influence of the measuring equipment on the measurement object during the measurement is determined. A schematic diagram of a magnetic sensor for measuring vibration displacement based on the effect of changing the pattern of magnetic field lines during the mutual movement of the sensor and the object of measurement is developed. The finite element magnetic sensor was modeled to optimize its design, as well as estimating the estimated sensitivity and error of the magnetic sensor. The total error of the measuring system is estimated taking into account the error of the Hall sensor, amplifier and analog-to-digital converter. The method was tested to measure the boring bar vibro displacement relative to the workpiece, the amplitude-frequency characteristics of these oscillations were obtained at idle and during boring, and the obtained measurement data were compared with the results of measurements using the obtained method using piezoelectric seismic sensors.