The mean and standard deviation (SD) of the pose estimation errors of the body segments from ten subject indoor experiments. The mean values of the EKF design are plotted by the solid lines and the one SD values are plotted as the dash lines. (a) Left-wrist Euler angle estimation statistics, (b) left-thigh Euler angle estimation statistics, (c) right-wrist Euler angle estimation statistics, (d) right-thigh Euler angle estimation statistics, and (e) trunk Euler angle estimation statistics.