非接触式动态响应测量的潜力,用于预测小尺寸或隐藏的损坏,在高度阻尼结构
Zakrya Azouz1, Barmak Honarvar Shakibaei Asli1, Muhammad Khan1
1Centre for Life-Cycle Engineering and Management, Faculty of Engineering and Applied Sciences, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK.
Sensors (Basel, Switzerland)
|September 28, 2024
概括
这项研究优化了基于振动的结构健康监测 (SHM) 的摄像头设置,以检测梁上的裂. 使用高速摄像头进行精确的动态响应测量,提高了损害评估的准确性.
科学领域:
- 工程 工程师 工程师 工程师
- 材料科学 材料科学 材料科学
- 非破坏性测试 不破坏性测试
背景情况:
- 基于振动的结构健康监测 (SHM) 对于评估结构完整性至关重要.
- 传统的SHM接触传感器在可访问性和覆盖范围方面存在局限性.
- 基于高速摄像机的测量为SHM提供了一个有前途的非接触式替代方案.
研究的目的:
- 调查摄像头设置 (速度和分辨率) 对动态响应测量准确性的影响,以检测受阻杆梁中的裂.
- 确定最佳的摄像头参数,以精确测量受结构损伤影响的振动特征.
- 为了建立裂深度,梁厚度和阻尼比率之间的关系,以有效量化损坏.
主要方法:
- 实验是在3D打印的烯丁 styrene (ABS) 悬臂梁上进行的,其裂深度各不相同.
- 坎尼边缘检测技术和快速里埃变换被用来分析高速摄像机捕获的振动数据.
- 摄像头设置,包括分辨率和率,被系统地改变,以评估它们对测量准确性的影响.
主要成果:
- 确定了相机分辨率和率的最佳组合,以准确地捕捉动态响应.
- 经验模型在预测自然频率方面达到98%以上的准确性,在预测共振幅度方面达到90%左右.
- 最佳的率被确定为光束的自然频率的2.4倍,用于准确的测量.
结论:
- 摄像机设置显著影响基于振动的SHM用于裂检测的准确性.
- 高速成像为结构中非接触式损伤评估提供了一种可行的方法.
- 该研究建立了一个框架,将裂纹特征和减震与可测量的振动参数联系起来.
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