Compressive Force Location Estimation with SuRE Method for Additively Manufactured Parts

Abstract

Electromechanical Impedance (EMI) approach is a widely used Structural Health Monitoring (SHM) method. The EMI of a piezoelectric disk is monitored with an impedance analyzer or impedance measurement chip. In addition to the cracks, EMI may monitor compressive forces and may be used for detection of loose bolts. Surface Response to Excitation (SuRE) method is a low-cost alternative to the EMI method. The SuRE method uses one piezoelectric disk for excitation and a sensor to monitor the surface wave propagation. Digitization and Fast Fourier Transformation (FFT) of the signal of the sensor, such as another piezoelectric disk, is satisfactory to monitor the characteristics of the system. The important weakness of both approaches is not being able to estimate the location of the defect at their minimal configuration. Recently, Additive Manufacturing (AM) has been used for the manufacturing of parts for various reasons. The layer by layer part building techniques of the AM methods allow for the hiding of geometric features behind the part’s exposed skin. Use of the hidden features of the additively manufactured parts is proposed in the paper to help the SuRE method for estimation of the location of defects. Experimental studies verified the validity of the proposed approach. In addition, the EMI methods may benefit from this same approach.