On the path to dynamic displacement detection with smartphone GNSS and accelerometer data

High-quality GNSS receivers and strong-motion accelerometers provide reliable and conventional data, now commonly used in early warning systems for geohazards, seismology, and civil engineering applications. Although their capability to deliver precise measurements has been established, their overall monitoring effectiveness can be constrained by the insufficient spatial coverage and densification of these sensors. Conversely, we are now in an era where mass-produced, affordable GNSS and MEMS sensors are widely available, and recent research indicates that they can offer precise GNSS and accelerometer observations. Particular attention is given to sensors embedded in modern smartphones. These widely used, but unprofessional sensors could potentially serve as detectors and providers of rapid, spatially dense information on dynamic movements. In this study, we explore and validate the applicability of precise dynamic displacement detection using GNSS observations and accelerometer data from sensors embedded in selected recent smartphones, such as Xiaomi 14. The validation was performed by means of retrieving artificial vibrations and dynamic motions, which were induced by the Quanser I-40 shake table. With the proposed combined GNSS and accelerometer solution based on smartphone data, we demonstrate the feasibility of precisely detecting sub-centimeter dynamic displacements. The results of the proposed approach based on smartphone data show that smartphones may soon be considered an auxiliary instrument in seismic and structural health monitoring applications.