The function converts the position of B (typically body) relative to E (typically Earth), the n-vector n_EB_E to cartesian position vector ("ECEF-vector"), p_EB_E, in meters.

n_EB_E2p_EB_E(n_EB_E, z_EB = 0, a = 6378137, f = 1/298.257223563)

Arguments

n_EB_E

n-vector of position B, decomposed in E (3x1 vector) (no unit)

z_EB

Depth of system B, relative to the ellipsoid (z_EB = -height) (m, default 0)

a

Semi-major axis of the Earth ellipsoid (m, default [WGS-84] 6378137)

f

Flattening of the Earth ellipsoid (no unit, default [WGS-84] 1/298.257223563)

Value

Cartesian position vector from E to B, decomposed in E (3x1 vector) (m)

Details

The calculation is exact, taking the ellipticity of the Earth into account.

It is also nonsingular as both n-vector and p-vector are nonsingular (except for the center of the Earth). The default ellipsoid model used is WGS-84, but other ellipsoids (or spheres) might be specified via the optional parameters a and f.

References

Kenneth Gade A Nonsingular Horizontal Position Representation. The Journal of Navigation, Volume 63, Issue 03, pp 395-417, July 2010.

See also

Examples

n_EB_E <- lat_lon2n_E(rad(1), rad(2)) n_EB_E2p_EB_E(n_EB_E)
#> [1] 6373287.3 222560.1 110568.8