OpenSense: Validation of IMU-based estimates of kinematics over long durations

Here we provide the dataset for validation of OpenSense, an open-source toolbox for Inertial-Measurement-Unit-based measurement of lower extremity kinematics over long durations (10 minutes). We computed IMU-based estimates of kinematics using sensor fusion and an inverse kinematics approach with a constrained biomechanical model. We measured kinematics for 11 subjects as they performed two 10-minute trials: (1) walking and turning, and (2) a repeated sequence of varied lower-extremity movements (sitting, standing, stair-climbing, side-stepping, walking, running). Subjects were young, free of any musculoskeletal injuries or disorders, and primarily male. The data was simultaneously collected from 8 IMUs (MTw Awinda, Xsens) and optical motion capture (Motion Analysis). To validate the approach, we compared the joint angles computed with IMU orientations to the joint angles computed from optical motion capture using root mean square (RMS) difference and Pearson correlations, and estimated drift using a linear regression on each subject’s RMS differences over time. We provide all of the data, models and scripts used in this workflow. OpenSense is now available with OpenSim 4.2 which can be found here: https://simtk.org/frs/index.php?group_id=91