I. INTRODUCTION
Early smartphones contained low-power accelerometers and magnetometers to measure device tilt. Tilt tracking allows users to interact with applications by simply rotating the device. For example, turning the phone on its side will rotate its interface from portrait to landscape. Modern smartphones include additional micro-electro mechanical gyroscopes. This combination of sensing hardware can also be found in motion capture systems in the form of inertial measurement units (IMU). This paper draws a parallel between smartphones and IMUs to answer one question: Is motion capture and activity tracking feasible using smartphone-driven body sensor networks?
The motion capture software environment [1] has been ported to the Android platform while targeting small handheld devices in terms of interface dimensions and touchscreen interaction. The proposed mobile application, previously intro- duced in the context of medicine and healthcare [2], encloses a 3D engine that is optimized to render kinematic models on the smartphone’s screen. The phone acts as an IMU by fusing the gyroscope, accelerometer and magnetometer data. The processed motion is applied to the kinematic rig and rendered on the smartphone screens to give the user an interpretable visualisation of the data.