REAUSYS-BTS: A Public BTS-IMU-Video Dataset for Upper-Limb Motion Assessment and Calibration

REAUSYS-BTS is a public multimodal dataset developed for the validation and calibration of wearable inertial sensing against a laboratory-grade optical motion-capture system. The dataset combines synchronized BTS Smart-DX Evo recordings, wireless inertial measurement unit (IMU) data, and multi-view RGB videos acquired simultaneously during upper-limb elbow-flexion experiments. The dataset includes raw BTS ASCII files containing three-dimensional marker trajectories sampled at 250 Hz, raw REAUSYS IMU recordings, synchronized RGB videos from frontal, lateral, and superior (zenith) viewpoints, synchronization metadata, plateau annotations, and calibration parameters used for offset estimation and agreement analysis. The dataset supports research on wearable sensing, optical motion validation, upper-limb kinematics, markerless pose estimation, multimodal sensor fusion, calibration methods, biomedical instrumentation, rehabilitation engineering, and reproducible motion-analysis pipelines.