What is the relationship between geodetic latitude and geocentric latitude?

Geodetic latitude is defined as the angle between the equatorial plane and the surface normal at a point on the ellipsoid, whereas geocentric latitude is defined as the angle between the equatorial plane and a radial line connecting the centre of the ellipsoid to a point on the surface (see figure).

Is Ecef geocentric?

The origin (point 0, 0, 0) is defined as the center of mass of Earth, hence the term geocentric coordinates. This means that ECEF rotates with the earth, and therefore coordinates of a point fixed on the surface of the earth do not change.

Is latitude geodetic or geocentric?

The geodetic latitude is what is normally used everywhere in PROJ when angular coordinates are expected or produced. The geocentric latitude (also called planetocentric latitude in the context of non-Earth bodies) is the angle between the equatorial plane and a line joining the body centre to the considered point.

How are geodetic coordinates converted to ECEF coordinates?

There are transformations that directly convert geodetic coordinates from one datum to another. There are more indirect transforms that convert from geodetic coordinates to ECEF coordinates, transform the ECEF coordinates from one datum to the another, then transform ECEF coordinates of the new datum back to geodetic coordinates.

How to convert a geodetic latitude to a geocentric latitude?

I. Geodetic to/from Geocentric Latitude A. Geodetic Latitude (φ, or φg) to Geocentric Latitude (φ′, or φc) There are many equations that can be used. One of the most common involves the tangent of the latitude. At a geodetic or ellipsoidal height h,  φ      + φ = − tan R h R tan 1 e N 2 N c

How to convert latitude and longitude to ECEF XYZ?

A. Latitude, Longitude, Height to ECEF xyz There is a closed form solution for this transformation. Given geodetic latitude, f, (what you find on maps), longitude, l, and ellipsoidal height h, then = – + f = + f l = + f l z ([1 e ] R h ) sin y ( R h) cos sin x ( R h ) cos cos N 2 N N Note that the longitude will be East Longitude.

How big is the error in Rn for geocentric latitude?

A similar magnitude error happens if you use geocentric latitude in computing Rn. (A 70 m error at 45 deg latitude). In both cases the maximum North-South position error occurs at an altitude of 1 earth radius at 45 deg latitude. This error is 1.1 meter. One iteration on latitude types makes this much less than a cm.