Driven by a wide range of real-world applications,significant efforts have recently been made to explore facile vibration measurement.Traditional vibration inspection systems are normally sensed via accelerometers,las...Driven by a wide range of real-world applications,significant efforts have recently been made to explore facile vibration measurement.Traditional vibration inspection systems are normally sensed via accelerometers,laser displacement sensors or velocimeters,and most of them are neither non-intrusive nor wide-spread.This paper presents a novel solution based on acoustic waves of commercial mobile phones to inspect mechanical vibration.The core observation is that the Doppler effect occurs when acoustic waves pass through a vibrating object.The study leverages this opportunity to build a bridge between the Doppler frequency excursion and the vibrating frequency of objects.The solution of difference operation of the reassignment vector is used to make time-frequency domain images more readable.Finally,by processing time-frequency images,the system further accomplishes two reconstruction approaches to find out the energy concentration of acoustic signals respectively based on ridges and clustering.Simulation and real-life applications are employed to show the effectiveness and practicability of the proposed approaches.Our prototype system can inspect the vibration period with a relative error of 0.08%.Furthermore,this paper studies two practical cases in life to associate our measurement solution with the requirements of daily life.展开更多
基金National Natural Science Foundation of China(Nos.61672151 and 61972081)DHU Distinguished Young Professor Program,China。
文摘Driven by a wide range of real-world applications,significant efforts have recently been made to explore facile vibration measurement.Traditional vibration inspection systems are normally sensed via accelerometers,laser displacement sensors or velocimeters,and most of them are neither non-intrusive nor wide-spread.This paper presents a novel solution based on acoustic waves of commercial mobile phones to inspect mechanical vibration.The core observation is that the Doppler effect occurs when acoustic waves pass through a vibrating object.The study leverages this opportunity to build a bridge between the Doppler frequency excursion and the vibrating frequency of objects.The solution of difference operation of the reassignment vector is used to make time-frequency domain images more readable.Finally,by processing time-frequency images,the system further accomplishes two reconstruction approaches to find out the energy concentration of acoustic signals respectively based on ridges and clustering.Simulation and real-life applications are employed to show the effectiveness and practicability of the proposed approaches.Our prototype system can inspect the vibration period with a relative error of 0.08%.Furthermore,this paper studies two practical cases in life to associate our measurement solution with the requirements of daily life.
