混合单频激励下连续扫描激光多普勒振动测试

提出了一种混合单频激励下激光连续扫描振动测试方法,提高了连续扫描激光多普勒振动测试效率。首先,基于单频激励下连续扫描激光多普勒振动测试的原理,研究了混合单频激励下连续扫描激光多普勒振动测试技术,提出了适合混合单频激励的结构工作变形提取方法;其次,通过仿真测试,从理论上验证了方法的有效性;最后,以悬臂梁结构为例,进行了连续扫描和离散点扫描测试的试验验证。结果表明,混合单频激励下的连续扫描激光振动测试及分析方法可准确获得结构工作变形,具有效率高、空间分辨率高等优点,对进一步的工程应用具有实用价值。

Continuous Scanning Laser Doppler Vibration Measurement Under Multi-frequency Excitation

A multi-frequency excitation method is proposed for higher efficiency of the continuous scanning laser Doppler vibration (CSLDV) measurement. First, based on the principle of a single frequency excitation for the CSLDV test, the approach of CSLDV measurement under a multi-frequency excitation is explored and the structural operational deflection shape(ODS) extraction based on a multi-frequency excitation is developed. Then, the simulation test of a beam structure is used to verify the effectiveness of the method. Finally, the experiments based on CSLDV and SLDV are both conducted on a cantilever beam structure. The results show that the structural ODS can be obtained accurately by both tests with the fact that the CSLDV method is more efficient and has higher spatial resolution than that of the SLDV method. This approach shows practical value for further engineering applications.