一种强大的多参考频域识别方法,从振动数据中提取动态特性
Sandro Diord Rescinho Amador1, Rune Brincker2
1Technical Univeristy of Denmark, Kgs. Lyngby, Denmark. sdio@dtu.dk.
Communications engineering
|August 9, 2024
概括
工程师现在可以使用新的频域方法更准确地从振动数据中提取结构动态特性. 这种强大的方法改进了现有技术,特别是对于噪音较大的测量.
科学领域:
- 结构动力学和振动分析分析
- 计算力学 计算力学 计算力学
- 实验模式分析的实验模式分析
背景情况:
- 从结构振动测试中提取动态特性对于系统分析至关重要.
- 现有的方法经常在准确性和稳定性方面扎,特别是在处理受噪声污染的数据时.
- 实验模式分析需要改进的技术.
研究的目的:
- 提出一种新的,强大的,准确的频域方法,从振动数据中提取动态特性.
- 加强结构系统中模式参数的识别.
- 解决当前方法的局限性,当应用到噪音振动测量时.
主要方法:
- 开发用于动态属性提取的频域模态模型.
- 拟议方法在模拟 (有限元模型) 和实验振动数据上的应用和验证.
- 使用稳定图,相对误差分析,模态保证标准 (MAC) 和频率响应函数合成的性能评估.
主要成果:
- 与最先进的技术相比,拟议的方法在识别动态性质方面表现出更高的清晰度和准确性.
- 在各种场景中有效应用,包括模拟数据和现实世界的结构 (平台样本,遗产法庭建筑).
- 在各种验证指标中观察到一致的性能改进.
结论:
- 开发的频域方法为从振动测试中提取动态特性提供了强大而准确的解决方案.
- 这种方法显著提高了模式参数识别的可靠性,特别是在测量噪声的情况下.
- 这些发现表明,对于结构健康监测和系统识别应用来说,这是一个有价值的进步.
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