An Experimental Study on Wave Propagation in an Additively Manufactured Monoatomic Chain

The objective of this study is to establish a reproducible experimental framework for investigation of wave propagation in monoatomic chains. The platform introduces suspension of the masses, self-centering casings, and direct stiffness calibration to minimize alignment errors and parameter variability which have limited the reliability of earlier prototypes. A chain of serpentine springs is fabricated using fused deposition modeling (FDM), and its stiffness is characterized using digital image correlation (DIC), ensuring accurate parameter input for numerical modeling. The system is carefully assembled with controlled suspension and precise alignment. It is then tested using a shaker excited by a sweep sine harmonic input, while the acceleration response is measured using accelerometers. The analytical dispersion relation is derived through Bloch’s theorem (unit-cell analysis), while the frequency-response function, used as a means of validation, is obtained via the modal analysis of a finite-chain model. Experimental frequency-response functions confirm the predicted cutoff frequency with close agreement between theory and measurement. The results demonstrated consistency across infinite unit-cell analysis, finite-chain modeling, and physical testing (a 1.3% experimental difference). The outcome is a validated methodology that links calibrated stiffness, precise suspension, and reproducible measurements, offering a reliable basis for systematic studies of dispersion and attenuation in printed lattice structures.