Characterizing and Mitigating Mounting’s Impact on Smartphone-Based Evaluation of Pavement Roughness

Smartphones are increasingly used for monitoring road roughness conditions. However, the smartphone-based roughness index estimation system (sRIE) is vulnerable to variations in vehicle type, driving speed, and mounting configuration. Among these factors, mounting has been underexplored, despite its significant influence on the smartphone-collected vehicle response data. This study aims to quantify the effects of four typical mountings on smartphone-collected response data and develop a method to correct their signals to accurately reflect the vehicle-body response. An empirical-based correction function was obtained from a laboratory vibration test and validated using real-world vehicle response data. This study found that the mountings amplify the signals in a 6–18 Hz frequency band, depending on their arm length and rigidity, while attenuating the amplitudes of vibrations above 30 Hz. The proposed method reduces the differences caused by different mountings through amplitude correction in frequency bands. This study provides insights into mounting’s effect on sRIE and contributes to crowdsourcing-based pavement roughness monitoring.