SUBJECT: Ph.D. Dissertation Defense
BY: Min Li
TIME: Friday, November 3, 2017, 1:00 p.m.
PLACE: GTMI (MARC) Building, 431
TITLE: Development of an Electromagnetic Sensing System for Field Reconstruction and Geometrical Feature Measurement
COMMITTEE: Dr. Kok-Meng Lee, Chair (Mechanical Engineering)
Dr. Shreyes N. Melkote (Mechanical Engineering)
Dr. Boris Prilutsky (Biological Sciences)
Dr. Yan Wang (Mechanical Engineering)
Dr. Yang Wang (Civil and Environmental Engineering)


This dissertation has been motivated by two practical applications: The first responds to a need to develop a geomagnetic field-based sensing system to help visually impaired patients locate objects and guide way-finding. The second is a method for intelligent manufacturing applications, where an eddy current is electromagnetically induced in a conductive workpiece for real-time measurements of geometrical features. This thesis addresses a common problem in these applications, which involves reconstruction of a physical field from limited measurements for characterizing geometrical features. Inspired by the simplicity of electromagnetic source-based models, this thesis has formulated the forward and inverse electromagnetic problems and derived computationally efficient closed-form solutions to provide a basis for developing a multi-function electromagnetic sensing system and reconstructing a physical field of interest. The source-based models have been employed in the design, analysis and optimization of the sensing system for the above-mentioned applications, upon which a prototype sensing system has been developed to serve as a test-bed for physical field reconstruction. An experimental investigation has been carried out to validate the concept feasibility of field reconstruction, verify the source-based models and evaluate the sensor performance. Apart from the development of a multi-function electromagnetic sensing system for geometrical feature measurements, the findings of this thesis have offered a basis of a general field-reconstruction method that has a spectrum of engineering applications.