Visible and infrared deflectometry for contactless and full-field vibration measurements

用于非接触式全场振动测量的可见光和红外偏转测量

• 批准号: RGPIN-2022-04907
• 负责人: Robin, Olivier
• 金额: $ 2.04万
• 依托单位: Université de Sherbrooke
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=754499
• 关键词: Visible; infrared; deflectometry; contactless; full

Mechanical, acoustical or aerodynamic excitations can induce structural vibrations, and the latter are of interest in noise and vibration monitoring and control, material testing and structural dynamics. Vibrations have been measured for more than a century using accelerometers. Contactless vibration measurements were introduced with the laser Doppler vibrometry that allows 2D and 3D vibration measurement on structures. In parallel, contactless and full-field vibration measurements have burgeoned with the availability of high-speed digital cameras. By imaging an entire surface at once, they can provide time- and space-resolved measurements that are well-suited for the study of non-stationary or transient phenomena. Among well-established techniques like digital image correlation, deflectometry is a measurement method gaining interest. Deflectometry provides reliable measurements with good sensitivity, all with a simple setup and a single camera. A recent progress is the successful application of deflectometry in the infrared spectrum for dynamic vibration measurements. Moving to the infrared domain and longer wavelengths compared to the visible domain relaxes the constraints on the surface roughness of a tested specimen, and allows measurements to be performed on common and unprepared surfaces. The two main objectives of the program are to increase the technology readiness level and to extend the application range of the deflectometry method. The development of an integrated measurement system to be used in laboratory and research contexts will play a centralizing role, being developed and used in projects conducted with several collaborators. Covered topics will range from the characterization of plane and curved isotropic panels and eco-materials, to identification methods concerning loadings or materials properties. Two novel implementations of deflectometry will also be considered at moderate frame rates (< 1000-2000 images per second). The first will be based on the development of a multi-camera setup using industrial grade cameras, and the second will be based on the development of a portable device (cellular phone, tablet) to evaluate the possibility of performing dynamic deflectometry measurements using such devices. The effectiveness of infrared deflectometry for dynamic vibration measurements was only established in 2021, and this work is expected to generate a subsequent stream of scientific developments and publications. The availability of a tool will broaden the range of potential applications for the deflectometry technique, and will provide a strategic advantage for industries and research in Canada. The availability of reliable full-field contactless measurements can pave the way towards a « materials and structures testing 2.0 » paradigm. This work will finally provide a perfect setting for training students by providing practical and modern industry-encouraged research and education topics in a multidisciplinary context.

机械、声学或空气动力学激励可以引起结构振动，后者在噪声和振动监测和控制、材料测试和结构动力学方面引起了人们的兴趣，一个多世纪以来，人们一直在使用加速度计来测量振动。激光多普勒振动测量可以对结构进行 2D 和 3D 振动测量，同时，随着高速数码相机的出现，通过对整个表面进行成像，非接触式和全场振动测量得到了蓬勃发展。一旦，它们可以提供非常适合非平稳或瞬态现象研究的时间和空间分辨测量，在数字图像相关等成熟技术中，偏转测量是一种引起人们兴趣的测量方法。具有良好的灵敏度，所有这些都具有简单的设置和单个相机，最近的进展是偏转测量在红外光谱中成功应用于动态振动测量，与可见光域相比，波长更长，从而放松了对红外光谱的限制。该计划的两个主要目标是提高技术准备水平和扩展偏转测量方法的应用范围。将在实验室和研究环境中使用的系统将发挥集中作用，正在与多个合作者进行的项目中开发和使用，涵盖的主题范围从平面和弯曲各向同性面板和生态材料的表征，到有关载荷或材料的识别方法。材料还将考虑以中等帧速率（< 每秒 1000-2000 个图像）实现偏转测量的两种新颖方法，第一种将基于使用工业级相机的多相机设置的开发，第二种将基于使用工业级相机的多相机设置。开发便携式设备（手机、平板电脑）以评估使用此类设备进行动态偏转测量的可能性。红外偏转测量在动态振动测量中的有效性直到 2021 年才确定，这项工作预计将在 2021 年实现。产生一系列的科学进展和出版物。工具的可用性将扩大偏转测量技术的潜在应用范围，并将为加拿大的工业和研究提供战略优势。这项工作最终将为学生提供一个完美的环境，在多学科背景下提供实用且现代行业鼓励的研究和教育主题。