A Smartphone-Based Acquisition System for Hips Rotation Fluency Assessment
This work addresses the need for accessible movement assessment tools in healthcare or sports, but it is incremental as it applies existing methods to a new application area.
The paper tackled the problem of assessing hips rotation fluency during 3D movements by estimating the kinematic jerk index from gyroscopic signals acquired via a smartphone app, resulting in a system that processes data in real-time or offline to return this index.
The present contribution is motivated by recent studies on the assessment of the fluency of body movements during complex motor tasks. In particular, we focus on the estimation of the Cartesian kinematic jerk (namely, the derivative of the acceleration) of the hips' orientation during a full three-dimensional movement. The kinematic jerk index is estimated on the basis of gyroscopic signals acquired through a smartphone. A specific free mobile application available for the Android mobile operating system, HyperIMU, is used to acquire the gyroscopic signals and to transmit them to a personal computer via a User Datagram Protocol (UDP) through a wireless network. The personal computer elaborates the acquired data through a MATLAB script, either in real time or offline, and returns the kinematic jerk index associated to a motor task.