Development of strain gauge base on

• Main Authors: BO-XIAN HUANG, 黃柏憲
• Other Authors: CHIH-YUNG HUANG
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/87804927387790320518

碩士 === 國立勤益科技大學 === 機械工程系 === 101 === Surface acoustic wave device applications in life have been quite mature.Since the surface acoustic wave device itself has small size, low cost, high stability and suitable for use in harsh environments and the development of wireless type, etc.Therefore, it is widely used on sensors, the resonator and filter. This studyuses 41°YX Lithium-Niobium acid (LiNbO3) base materials to make surface acoustic wave strain gauge. The form of wave propagation is cuts to leak (SH wave) Surface acoustic wave, which is more faster speed and higher electromechanical coupling coefficient. Stress and strain using surface acoustic wave strain gauge, to plating in LiNbO3 thin film on the surface of aluminium spacing changes, thereby changing its center frequency. Based on the change in its center frequency, we can estimate the load weight. Simulation used in PCB glass fiber Board as testing assumptions, with the formula estimates the Central frequency offset, attenuation, etc. Simulation results show the linear relationship with loading and center frequency offset. Simulation of temperature effect on surface acoustic wave strain gage and compensation amendment would make its surface acoustic wave application on strain gauge more precisely. The study was designed with 41 °Y-cut LiNbO3 on the base,velocity of the surface acoustic wave generated 4792 m/s. The center frequency of about 59.9MHz delay line type and resonator type surface acoustic wave with the strain gauge.Using CC-33A strain adhesive mount the PCB specimen ,the test piece holding the material tensile testing machine for uniaxial tensile strain, and the test strip quilt installation are compared with a commercially available strain gauge sensitivity.The strain on the SAW device to the center frequency shift are measured by the network vector analyzer. Experimental results show thattemperature on strain gauges for surface acoustic is about 16.5kHz/℃. The effect of center frequency is shifted to lower frequencies and strain gages for the impact of surface acoustic wave delay line type were approximately every percent change in strain produced 23.067kHz frequency offset reduced. Strain gages for the impact of surface acoustic wave resonator type were approximately every percent change in strain produced 67.515kHz frequency offset reduced. The sensitivity of commercially available strain gauges in less than 1.5% strain is poorer and the linearity only showed when strain is greater than 1.5%. The resonator type surface acoustic wave strain gauge in this study becomes linear from the start and show better linearity ratio.