A novel electromagnetic tomography(EMT)system for defect detection of high-speed rail wheel is proposed,which differs from traditional electromagnetic tomography systems in its spatial arrangements of coils.A U-shaped...A novel electromagnetic tomography(EMT)system for defect detection of high-speed rail wheel is proposed,which differs from traditional electromagnetic tomography systems in its spatial arrangements of coils.A U-shaped sensor array was designed,and then a simulation model was built with the low frequency electromagnetic simulation software.Three different algorithms were applied to perform image reconstruction,therefore the defects can be detected from the reconstructed images.Based on the simulation results,an experimental system was built and image reconstruction were performed with the measured data.The reconstructed images obtained both from numerical simulation and experimental system indicated the locations of the defects of the wheel,which verified the feasibility of the EMT system and revealed its good application prospect in the future.展开更多
In this paper,a fast-speed and real-time online rail inspection method based on half-cycle orthogonal power demodulation algorithm is proposed.For this method,the power characters of de-tection signal which represent ...In this paper,a fast-speed and real-time online rail inspection method based on half-cycle orthogonal power demodulation algorithm is proposed.For this method,the power characters of de-tection signal which represent the degree of rail track can be calculated using only half-cycle detec-tion signal because of the symmetry characteristic of detected sine signal and reference signal.The theoretical analysis,simulation results and experiment results show that the demodulation preci-sion of proposed method is almost equal to fast Fourier transform(FFT)demodulation method and orthogonal demodulation method,but has high demodulation efficiency and less FPGA resources cost.A high-speed experiment system based on three coils structured sensor is built for rail inspec-tion experiment at a moving speed of 200 km/h.The experiment results show that proposed meth-od is more effective for rail inspection and the time resolution of proposed method is double of clas-sic method that based on FFT and orthogonal.展开更多
基金Supported by the National Natural Science Foundation of China(61771041)。
文摘A novel electromagnetic tomography(EMT)system for defect detection of high-speed rail wheel is proposed,which differs from traditional electromagnetic tomography systems in its spatial arrangements of coils.A U-shaped sensor array was designed,and then a simulation model was built with the low frequency electromagnetic simulation software.Three different algorithms were applied to perform image reconstruction,therefore the defects can be detected from the reconstructed images.Based on the simulation results,an experimental system was built and image reconstruction were performed with the measured data.The reconstructed images obtained both from numerical simulation and experimental system indicated the locations of the defects of the wheel,which verified the feasibility of the EMT system and revealed its good application prospect in the future.
基金supported by the National Natural Science Found-ation of China(No.61771041).
文摘In this paper,a fast-speed and real-time online rail inspection method based on half-cycle orthogonal power demodulation algorithm is proposed.For this method,the power characters of de-tection signal which represent the degree of rail track can be calculated using only half-cycle detec-tion signal because of the symmetry characteristic of detected sine signal and reference signal.The theoretical analysis,simulation results and experiment results show that the demodulation preci-sion of proposed method is almost equal to fast Fourier transform(FFT)demodulation method and orthogonal demodulation method,but has high demodulation efficiency and less FPGA resources cost.A high-speed experiment system based on three coils structured sensor is built for rail inspec-tion experiment at a moving speed of 200 km/h.The experiment results show that proposed meth-od is more effective for rail inspection and the time resolution of proposed method is double of clas-sic method that based on FFT and orthogonal.
