Figure 2.

Noise characteristics of angular positions in pitch and roll directions. (a) Noise in pitch direction without the EKF estimation. (b) Noise in roll direction without the EKF estimation. (c) Predicted Gaussian curve (solid line) of noise distribution (points) in pitch direction. (d) Predicted Gaussian curve (solid line) of noise distribution (points) in roll direction. Note that values for R² range from 0 to 1 and indicate the goodness of fit between the predicted Gaussian curve and the noise distribution.