Research And Design Of Digital Dynamic Stress Strain Gauges

Due to the large-scale and complicated engineering,it is difficult to solve the problem of stress and strain of engineering structure by theoretical calculation.Moreover,the accuracy of engineering analysis is closely related to the measurement accuracy of measuring instruments.In fact,the resistance strain gauge is a kind of precise electronic equipment that can measure the strain signal by measuring the resistance change rate.In this paper,the research and design of digital dynamic stress and strain gauge is mainly used to improve the measurement accuracy.At the same time,a dynamic strain signal analysis method based on EEMD and spectrum correction is proposed to deal with the non-stationary characteristics of dynamic strain signals.In order to improve the measurement accuracy,this paper mainly studies the strain bridge,the power supply of the bridge,the signal conditioning circuit and the balance calibration.The measurement error caused by each module is analyzed in depth,and then the improvement scheme is put forward.Finally,the corresponding hardware circuit is designed.In the analysis of dynamic strain signals,the measured strain signals usually contain a large number of random noises,which is the superposition of many strain signals.Therefore,the signal has a significant non-stationary characteristic.As the spectrum analysis precision based on the existing processing method(wavelet method,EMD method,analytical modal research,etc.)is not high,therefore,the analysis method of strain signal and spectrum correction based on EEMD is proposed,and the simulation is done.In this paper,the overall performance of the dynamic strain gauge is designed.It includes the power supply ripple rate test,conditioning signal test,FPGA series parallel conversion test,zero drift test,strain gauge measurement accuracy test and spectrum analysis precision test.The experimental results show that the dynamic strain gauge designed in this paper has achieved the design target,and improved the measurement accuracy and the analysis accuracy.Finally,the paper makes a summary of the article,and looks forward to the future research and improvement combined with the development trend of the international instruments.