Development of Instrumentation for Measurement of Microscopic Dynamic Motions in Physical Systems

Wayne State University, Detroit MI

Investigators

Abstract

Abstract Dynamic behavior of microelectromechanical systems (MEMS), microscopic weld-zone dynamics during ultrasonic welding, sonic-infrared imaging for non-destructive evaluation of cracks, vibration-assisted processing of nanocomposites and imaging of microscopic vibro-acoustic sources are all subjects of current or proposed multidisciplinary research programs at Wayne State University (WSU), and all of these research efforts would be significantly enhanced by adding the capability for precise measurement of complex high frequency microscopic motions and the distribution of those motions over finite regions in physical systems. Such measurement capabilities are not currently available at WSU, and this project addresses that need by outlining a program for systematic acquisition and development of new instruments. The acquisition and development activities are tightly integrated. The micro scanning laser vibrometer has the capability to perform full modal analyses related to out-of-plane motions in micron-sized regions, while the new 3-D Nano-imager will be developed to provide full 3-D motion measurements of nanometer-sized regions. The proposed 3-D Nano-imager will be developed using two methods, a new optical measuring method based on the inverse scattering phase retrieval, and stroboscopic interferometer based three dimensional (3D) measurement technology. Both systems are needed for the following reasons; (1) motion measurements generated by the newly developed 3-D Nano-Imager system must be validated by comparison with independent measurements, and the micro scanning laser vibrometer system would provide that validation capability, (2) the micro scanning laser vibrometer system can measure out-of-plane motions of micron-sized systems, whereas the developed 3-D Nano-Imager system will extend the measurement capabilities to full 3-D motions of nanometer-sized systems, (3) the micro scanning laser vibrometer system would be available for our research immediately upon purchase and installation, whereas it is anticipated that the development of the 3-D Nano-Imager system will take at least one year, (4) both systems can be used to some degree in all of the research projects described in this proposal. The outcome of the research conducted with the requested instruments will add significantly to the knowledge base in the areas of MEMS devices, sensors based testing, ultrasonic welding, nondestructive testing of materials and structures, processing of nanocomposites, and imaging of noise and vibration sources. Graduate and undergraduate students will be trained in state-of-the-art techniques using state-of-the-art instruments. The results of the research will also be a source of course projects for a large pool of local engineers, undergraduate and graduate students, particularly from underrepresented groups.