title: An optimized Kalman filter for the estimate of trunk orientation from inertial sensors data during treadmill walking.
abstract: The aim of this study was the fine tuning of a Kalman filter with the intent to provide optimal estimates of lower trunk orientation in the frontal and sagittal planes during treadmill walking at different speeds using measured linear acceleration and angular velocity components represented in a local system of reference. Data were simultaneously collected using both an inertial measurement unit (IMU) and a stereophotogrammetric system from three healthy subjects walking on a treadmill at natural, slow and fast speeds. These data were used to estimate the parameters of the Kalman filter that minimized the difference between the trunk orientations provided by the filter and those obtained through stereophotogrammetry. The optimized parameters were then used to process the data collected from a further 15 healthy subjects of both genders and different anthropometry performing the same walking tasks with the aim of determining the robustness of the filter set up. The filter proved to be very robust. The root mean square values of the differences between the angles estimated through the IMU and through stereophotogrammetry were lower than 1.0° and the correlation coefficients between the corresponding curves were greater than 0.91. The proposed filter design can be used to reliably estimate trunk lateral and frontal bending during walking from inertial sensor data. Further studies are needed to determine the filter parameters that are most suitable for other motor tasks.
authors: Laboratory of Locomotor Apparatus Bioengineering, Department of Human Movement and Sport Sciences, Università degli Studi di Roma Foro Italico, Piazza Lauro De Bosis, 6, 00135 Rome, Italy.
authors: Claudia
authors: C
authors: Mazzà
authors: Marco
authors: M
authors: Donati
authors: John
authors: J
authors: McCamley
authors: Pietro
authors: P
authors: Picerno
authors: Aurelio
authors: A
authors: Cappozzo
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D005684:Gait; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement; D010780:Photogrammetry; D012815:Signal Processing, Computer-Assisted; D016138:Walking / Q000502:physiology*; D055815:Young Adult