Fig. 4. Boxing motion capture results of forearm wearing a device.
a The subject wears a device on his wrist and conducts boxing activity. b–c The magnitude of motion acceleration measured by our device and inertial method, respectively (b), and the corresponding errors (c). High dynamic motion with motion acceleration more than 120 m/s2 is observed. d–e The tri-axis motion velocity measured by our device and inertial method, respectively (d), and the corresponding errors (e). f–i The attitude estimation results of roll angle γ (f) and pitch angle θ (h), respectively, and the corresponding attitude errors by our device and inertial method respectively (g and i). Motion capture results of optical VICON system are used as reference values.