Estimating Center of Mass Kinematics During Perturbed Human Standing Using Accelerometers.

Autor: Hnat, Sandra K., Audu, Musa L., Triolo, Ronald J., Quinn, Roger D.
Předmět:
Zdroj: Journal of Applied Biomechanics; Oct2021, Vol. 37 Issue 5, p415-424, 10p, 1 Color Photograph, 3 Diagrams, 2 Charts, 2 Graphs
Abstrakt: Estimating center of mass (COM) through sensor measurements is done to maintain walking and standing stability with exoskeletons. The authors present a method for estimating COM kinematics through an artificial neural network, which was trained by minimizing the mean squared error between COM displacements measured by a gold-standard motion capture system and recorded acceleration signals from body-mounted accelerometers. A total of 5 able-bodied participants were destabilized during standing through: (1) unexpected perturbations caused by 4 linear actuators pulling on the waist and (2) volitionally moving weighted jars on a shelf. Each movement type was averaged across all participants. The algorithm's performance was quantified by the root mean square error and coefficient of determination (R²) calculated from both the entire trial and during each perturbation type. Throughout the trials and movement types, the average coefficient of determination was 0.83, with 89% of the movements with R² > .70, while the average root mean square error ranged between 7.3% and 22.0%, corresponding to 0.5- and 0.94-cm error in both the coronal and sagittal planes. COM can be estimated in real time for balance control of exoskeletons for individuals with a spinal cord injury, and the procedure can be generalized for other gait studies. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index