How Do You Convert ENU to ECEF Coordinates?

[rjjansky]

Dear Readers,

It has been many (30+) years since I have had to work this kind of math and it is kickin' my butt. So, if you can help a software weenie with a need for a conversion formula for ENU to ECEF (or at least an explanation of things more elementary than what I have found thus far) it would be a great help. Not quite sure why it seems I can find plenty of discussions of going from ECEF to ENU but I must not be using the correct word set in my searches. Remember, please explain things as if I were a four year old.

Thanks in advance for what ever you can provide!

Cheers...

 

[mathman]

What are ENU and ECEF?

 

[rjjansky]

Sorry. They are different Earth axes conventions. ENU is East North Up while ECEF is Earth Centered Earth Fixed. There is also NED which is North East Down. At any rate, ECEF is Cartesian and ENU is not so those bits of data that I received in ENU need to be converted to ECEF in order to work through other formulas to estimate a new position. Being away from linear algebra and matrix math these many years has made it tough to get traction on solutions.

 

[mathman]

Since I am not familiar with the conventions by name, it would be helpful if you gave a complete definition for each.

 

[jasonRF]

The first item google gives me for "enu to ecef" is
http://www.navipedia.net/index.php/Transformations_between_ECEF_and_ENU_coordinates
Did you already look at the top google results for this topic? If so, what was confusing to you?

jason