MRI: Acquisition of Digital Image Correlation System for Real-Time 3D Measurements and Closed-Loop Control

这个主要研究仪器（MRI）项目涉及数字图像相关系统的收购。摄影测量技术可实时提供复杂测试系统三维位移的全场非接触测量。 其目的有两个方面，（a）在不使用应变计和差动传感器等传统接触式测量的情况下，检测和可视化受试品上出现的裂纹和应变集中，以及（B）开发自适应反馈信号，用于控制故障前和故障后状态下的力输入。Trilion Inc.的三维DIC测量系统。包括四对1200万像素的数码相机、Tritop坐标测量系统、图像处理工作站和控制器以及带有实时控制接口的Aramis处理软件。 将每对数码相机安装在具有专用照明的三脚架上，以提供视场内供试品的一系列立体图像。Aramis处理软件可跟踪10，000多个小平面点的坐标。它为结构材料测试提供变形场数据，直到最大载荷阻力，便携式仪器系统将为本科生和研究生提供新的机会，让他们熟悉数字图像相关系统的功能及其在各种研究项目中的应用，测试材料和基础设施组件到生物医学应用。 在十一个教师的指导下，土木和机械工程专业的学生将接受以下培训：（a）使用强大的成像来跟踪新兴的故障机制，以及（B）材料和结构的伺服控制测试领域。

This Major Research Instrumentation (MRI) project involves acquisition of a Digital Image Correlation System. The photogrammetric technology provides full-field non-contact measurements of 3D displacements of complex test systems in real-time. The intent is two-fold, (a) to detect and visualize emerging cracks and strain concentrations on test articles without the use of traditional contact measurements such as strain gauges and differential transducers, and (b) to develop an adaptive feed-back signal for controlling the force input in the pre- and post-failure regime. The 3-D DIC measurement system by Trilion Inc. includes four pairs of 12 megapixel digital cameras, the Tritop coordinate measurement system, an image processing workstation and controller, and the Aramis processing software with a real-time interface for control. Each pair of digital cameras is mounted on a tripod with dedicated lighting to provide a series of stereoscopic images of the test article within the field of view. The Aramis processing software tracks the coordinates of 10,000+ facet points. It provides deformation field data for structural materials testing up to and beyond their maximum load resistance, and progressive failure such as crack initiation and propagation in structural components and systems.The portable instrumentation system will provide new opportunities for undergraduate and graduate students to acquaint themselves with the capabilities of digital image correlation systems and their application to a variety of research projects spanning from testing materials and infrastructural components to biomedical applications. Under the direction of eleven faculty, students in Civil and Mechanical Engineering will be trained in (a) the use of powerful imaging to track emerging failure mechanisms, and (b) the field of servo-controlled testing of materials and structures.