Review of Smartphone Accelerometers for Usage in Research and Engineering

Modern smartphones are equipped with various sensors for different purposes. A common use, for example, is the determination of the device's orientation. Beyond that, researchers and engineers are increasingly utilizing the built-in sensors for measuring and monitoring applications. While many studies analyze the potential uses of these devices in scientific- or engineering-related applications, not much research has been devoted so far to the accuracy and reliability of smartphone sensor data itself. Therefore, in this study, we analyze the capabilities of smartphones to record acceleration data. For that purpose, we conducted several experiments with up to eight different Android devices to better understand the properties of these accelerometers compared to industry-grade sensors. Our experiments focus on typical accelerometer-related attributes like range, resolution, and noise, as well as system-related aspects like timestamp accuracy and clock drift. Using shaker rig experiments, we also analyzed the frequency responses and the dampening effect of smartphone cases. By illuminating the practical implications of sensor characteristics such as noise, bias, and frequency response, we aim to provide insights into how these factors affect the suitability of smartphones in real-world measurement applications, such as structural health monitoring, vehicular vibration analysis, and seismic activity detection. We show that smartphone sensors are capable enough for a wide range of applications but are, for example, rather limited in their frequency sensing capabilities. Our results are intended to help researchers and engineers assess whether smartphone sensors can meet their individual application requirements and to better understand the limits of these kinds of accelerometers.