A Study on the Improvement of the Accuracy for the Sensitivity of a Parallel Beam Load Cell

• Main Authors: CHENG,TA-YU, 鄭達裕
• Other Authors: CHANG,YUN
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/25281458053654585138

碩士 === 國立聯合大學 === 機械工程學系碩士班 === 105 === The main purpose of this study is that the theoretical calculation and finite element simulation for holes parallel beam force sensor structure design parameters and sensor sensitivity analysis, using 5083 aluminum alloy processing test, to verify compliance with the actual analysis. According to the results of this study, it is found that the theoretical strain value calculated by the traditional analytical design method is very different from that measured by the actual strain gauge. The theoretical strain value obtained by the solution of the traditional cubic statically indeterminate structure is in good agreement with the FEA results. However, the FEA results in regions other than the peak strain region are slightly higher than the theoretical values. The maximum strain occurs at the location 0.07r outside the design measurement point (x = r and x = a + r). This result is different from the previous literature claiming that maximum strain will occur at the design measurement point (where the beam section height h is minimized). Since the normal strain variation in the X direction is quite large in the strain gauge length range, the strain measurement value εave of the strain gauge is smaller than the design value. With the strain gauge length l and r / s value of the difference, only about the design strain value ε0 95% -60%, so that the sensor sensitivity decreased significantly. This study shows the main cause of the error, 1. strain gauge output strain gauge for the average strain, rather than the measurement point of the strain value. 2. The stress state of the centripetal surface of the force sensor, the plane stress state assumed by the non-theory, is similar to the plane strain state. Therefore, the results of the general 2D statically indeterminate erection, and the actual measurement and 3D wired element analysis results are quite different. The experimental results show that the 3D finite element analysis of the simulation results, the results and experimental data is extremely stable, the error is only 1% or less, so the study proposed correction factor C to change the center hole a two holes to correct the strain gauge strain measurement Between the value and the design value of the error.