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Kuu
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Homework Statement
I have a body which is instantiated on Earth at some latitude, longitude and altitude. The body has acceleration which is expressed in body coordinates and the acceleration can be integrated to obtain the velocity vector which is also expressed in body coordinates.
ECI and ECEF frames are located at the center of the Earth and NED frame is located at the bodys center of gravity. The current angle of the body is presented with Euler angles which are expressed with respect to NED frame.
How I can transform the body velocity vector to ECEF coordinates so that I can integrate a new position for the body in the ECEF frame? The position in the ECEF frame can then be transformed to latitude, longitude and altitude?
This is not exactly a homework problem but something I've been trying to understand.
Homework Equations
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The Attempt at a Solution
I was thinking something like this:
- Create transformation matrix ##T^{N0}_{I}## which transforms from the ECI frame to the initial NED frame. (NED frame at the point in which the body is instantiated).
- Create transformation matrix ##T^{B}_{N0}## which transforms from the initial NED frame to the current body orientation.
- Create transformation matrix ##T^{E}_{I}## which transforms from inertial frame to current ECEF frame. Transpose: ##T^{I}_{E}## transforms from ECEF to inertial frame
- Combine the transformations to get: ##T^{B}_{E} = T^{B}_{N0} T^{N0}_{I} T^{I}_{E}## which transforms from ECEF to body and its transpose ##T^{E}_{B}## which transforms from body to ECEF frame