inclination.Rd
This function is used to estimate the local magnetic field vector inclination angle directly from acceleration and magnetic field measurements.
inclination(A, M, fc = NULL)
A | The accelerometer data structure or signal matrix, A = [ax,ay,az] in any consistent unit (e.g., in g or m/s2). A can be in any frame. |
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M | The magnetometer data structure or signal matrix, M = [mx,my,mz] in any consistent unit (e.g., in uT or Gauss). M must be in the same frame as A. |
fc | (optional) The cut-off frequency of a low-pass filter to apply to A and M before computing the inclination angle. The filter cut-off frequency is with respect to 1=Nyquist frequency. Filtering adds no group delay. If fc is not specified, no filtering is performed. |
The magnetic field inclination angle in radians.
Output sampling rate is the same as the input sampling rate.
Frame: This function assumes a [north,east,up] navigation frame and a [forward,right,up] local frame. In these frames, the magnetic field vector has a positive inclination angle when it points below the horizon. Other frames can be used as long as A and M are in the same frame however the interpretation of incl will differ accordingly.
if (FALSE) { A <- matrix(c(1, -0.5, 0.1, 0.8, -0.2, 0.6, 0.5, -0.9, -0.7), byrow = TRUE, nrow = 3, ncol = 3 ) M <- matrix(c(1.3, -0.25, 0.16, 0.78, -0.3, 0.5, 0.5, -0.49, -0.6), byrow = TRUE, nrow = 3, ncol = 3 ) incl <- inclination(A, M) # Results: incl = -0.91595 radians. }