Shear-wave multi-frequency pulse for single-shot viscoelastic sensing

Abstract

Time-resolved estimation of viscoelastic properties is essential for capturing dynamic mechanical changes in soft materials and biological tissues. Viscoelastic parameters can be estimated from shear-wave velocity (SWV) dispersion, but repeated excitations at different frequencies limit temporal resolution. We introduce a method of SWV dispersion measurement using a shear-wave multi-frequency pulse (SW-MFP) that encodes several chosen frequencies into a single excitation. Shear elasticity and viscosity estimates are obtained by fitting the measured SWV dispersion to the Kelvin–Voigt model. Experiments were performed using a compact setup with dual plane wave ultrasound transducers and a miniaturized SW actuator. Tissue-mimicking phantoms with varied viscoelastic properties were distinguished by their SWV dispersion curves and corresponding viscoelastic parameter estimates. These results demonstrate SW-MFP for single-shot viscoelastic sensing, providing a pathway toward real-time viscoelastic characterization of dynamic soft materials in biomedical and industrial applications.