Design & Fabrication of Embedded Hardware Based Multi Frequency Eddy Current NDT System

  • Sayed Asim Ahmed
  • Salar Bin Javaid
  • Syed Sohaib Haider


Eddy Current Testing (ECT) is a branch of Non Destructive Testing (NDT) Techniques. It has a wide area of applications ranging from the aerospace to the nuclear industries. At present there has been modest development in the field of ECT indigenously. ECT equipment is usually imported from abroad at a large cost. The goal of this project is to design and fabricate an Embedded Hardware Based Multi‐Frequency Based Eddy Current Testing System.

The project involves the design and fabrication of an Embedded Hardware based Multi Frequency Eddy Current Testing System for the detection of cracks, flaws, voids and discontinuities in various conductive materials. After the successful completion of the PC based ECT System during the previous academic term, the students' goal is to refine the design by pursuing a more portable and versatile system.

The system consists of a transducer coil, which is energized by a constant peak alternating current source at multiple frequencies. The transducer provides a frequency modulated signal which is prepared and demodulated in order to acquire the message signal, in this case the message signal is the signal from a crack or flaw. The output signal is sent to the embedded hardware via a specifically designed Data Acquisition (DAQ) Card. Using the on board OS and software, this signal will then be processed and plotted on a touch screen display. Furthermore, a Graphical User Interface (GUI) will be developed for the Impedance Signal, incorporating real time plotting and data comparison features. Using impedance information at multiple frequencies, data analysis techniques will be applied in order for flaw diagnostics and characterization.