Design And Experiment Of Strain Gauge Yarn Tension Sensor

With the rapid development of textile technology,the quality requirements and production speed of fabrics are getting higher and higher,which puts demands on yarn tension detection.Strain gauge yarn tension sensors are most widely used in the production of textile enterprises,and in the study of the sensor performance,most scholars are directly given the model of the sensitive elements in the sensor and only analyze the static performance of the sensor,but the dynamic performance of the sensor is more realistic and reliable reflection of the yarn tension size.Therefore,it is especially critical to improve the sensor performance and dynamic performance testing.In this paper,based on ANSYS finite element analysis,a sensitive element structure that can generate large strain and high intrinsic frequency is designed.At the same time,a dynamic test method is designed and a system for dynamic performance testing of the sensor is built.The main research contents and innovative work of this paper are as follows:(1)In order to improve the sensitivity and stability of the sensor,based on the structural characteristics of the sensitive element and the strain gauge principle,the sensitive element structure was optimized by edge cutting and hole digging operations,which were analyzed using correlation analysis,parametric analysis and modal analysis in ANSYS finite element.The results of the analysis: the strain value in the patch area is greatly improved and the first-order intrinsic frequency of the sensitive element is increased by 654.4 Hz,which ensures the sensitivity and stability of the sensor.(2)To further investigate the performance of the optimized sensitive elements,twelve groups of sensors were set up according to three parameters: material,thickness and hole angle,and twelve groups of sensors were compared and tested by the control variable method.(angle).(3)In order to understand the static performance of the above two sensors,an experimental setup was built and tested.According to the calculation method of national standard and experimental data processing,the test results are: the tension measurement range of Fe-0.3-90° sensor is 0～155c N,sensitivity is 0.01788V/c N,linearity is 0.566%,repeatability is 0.647%,hysteresis is 0.524%,and accuracy is 1.007%;the tension measurement range of Cu-0.2-90° sensor is 0～50c N,sensitivity is 0.05621V/c N,linearity is 0.582%,repeatability is 1.007%;the tension measurement range of Cu-0.2-90° sensor is 0～50c N,sensitivity is 0.05621V/c N,linearity is 0.582%,repeatability is 0.713%,hysteresis is 0.569%,and accuracy is 1.082%.It meets the needs of yarn tension detection.(4)To evaluate the dynamic response capability of the sensor and the application range of the sensor.According to the decibel definition amplitude ratio formula,the test method is proposed: by controlling the vibration amplitude(displacement),the output voltage of the sensor is measured at different vibration frequencies.A dynamic test system with high accuracy of displacement control was built and tested.The test results: 1.At low frequencies and small amplitude,the dynamic response capability of the sensor is high and the response capability of the Cu-0.2-90° sensor is higher than that of the Fe-0.3-90° sensor;2.With the increase of frequency,the response capability of the sensor decreases;3.capability decreases at a lower rate than that of the Cu-0.2-90° sensor.Based on the test results,the application range of the sensor is proposed for different yarn types.In addition,the time domain performance index of the sensor was obtained by step excitation of the sensor with the system: the overshoot of Fe-0.3-90° sensor was 11.43%,the response time was 1.75 ms,the rise time was 0.34 ms,and the peak time was 0.51 ms.The overshoot of Cu-0.2-90° sensor was 8.7%,the response time was 1.5ms,the rise time is 0.22 ms and the peak time is 0.34 ms.(5)Sensor field test.The designed sensor was compared with the standard sensor by changing the motor speed for the purpose of changing the yarn vibration frequency.The experimental results are: the maximum error value is about 5%,and the error value increases with the increase of motor speed,which verifies the results in the dynamic performance test.This project proposes a sensitive element structure that can generate large strain and high intrinsic frequency to improve the performance of strain gauge yarn tension sensor,and designs a dynamic test system.The sensor with the sensitive element structure is characterized by high precision,fast response and good stability;the dynamic test system is characterized by high testing accuracy and universality.At the same time,the designed sensor and dynamic test system have engineering application value.