Papers by Keyword: Vibration Measuring

Abstract: The development of industrial automation has urged the vibratory feeding system to become an efficient automation equipment. With vibration as the operating mode of the vibratory transmission system, the moving mass has a crucial impact on transmission rate and efficiency of the material. Therefore, it is necessary to carry out real-time vibration measurement of the vibratory feeding system and get feedback to the control system, so that the vibratory feeding system works more efficiently. The paper provides two vibration measuring techniques which separately uses the displacement sensor and the acceleration sensor. Through comparing the two methods, it provides a strong basis for choosing better measuring technique for vibratory feeding system.

Abstract: Magnetic Suspension Flywheel (MSFW) is regarded as a promising attitude control actuator for the ultra-precision and long life-span spacecraft. The output vibration of an operating MSFW is an important criterion to evaluate the system’s performance. Based on the dynamics model of rotor with the residual imbalances and the transfer functions of the controller, the restoring electromagnetic forces and torques for the suspension of the rotor is calculated. Then a testing rig was designed to measure the displacements, currents and vibration outputs of the MSFW. The vibrations of the basement caused by reactions of the restoring forces and torques are calculated. In the end, the displacements, currents and vibrations of the operating MSFW are measured to evaluate the performance of the MSFW.

Abstract: Measured vibration response signals are inevitably contaminated with noise originating from test environment as well as electronic devices. This situation often leads to serious difficulties in many applications as they require high-quality measured data. This paper presents a signal-noise separation method for measured impulsive response functions (IRFs) based on structured low rank approximation (SLRA). The proposed method was tested with a steel cantilever beam, which was subjected to impulsive excitation. Gabor transform was also employed to process measured signals. The results show that this method can give a reliable separation of signal and noise, which will enhance the accuracy of various applications that rely on measured signals.

Abstract: Measured vibration response signals are inevitably contaminated with noise when a data acquisition system is used for an experimental measurement. This situation often leads to serious difficulties in identifying the modal parameters with proper accuracy. This paper presents a noise cancellation method for measured impulsive response functions (IRFs) based on structured low rank approximation (SLRA) so as to improve the accuracy of the modal parameters identification. Numerical study of a cantilever beam model is carried out to demonstrate the performance of the proposed method. The results show that this method can remove noise from measured IRFs efficiently, and the modal parameter identifications based on the filtered IRFs are very good.

Abstract: Measured impulsive response functions (IRFs) are inevitably contaminated with noise when a data acquisition system is used for an experimental measurement. This situation often leads to serious difficulties in identifying the modal parameters with proper accuracy. This paper presents a noise reduction method for measured IRFs based on structured low rank approximation (SLRA) so as to improve the accuracy of the modal identification. A cantilever beam experiment is used to demonstrate the performance of the proposed method. The results show that this method can remove noise from measured IRFs efficiently, and the modal parameter identifications based on the filtered IRFs are very good.