How to make something independent of the coordinate frame?

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TL;DR
what become independent of coordinate frame when using moving trihedral
In page 49, chap 8 of the book "classical mechanics point particles and relativity" of Greiner, there is the following sentence:
"In order to become independent of the coordinate frame, a set of orthogonal unit vectors is put at the point of the trajectory of the mass point given by ##s##."
Here, what become independent of the coordinate frame? And how using moving trihedral make some quantity independence of the coordinate frame?
A simple, concrete example to illustrate is welcome, like consider the orbit of mass point when throw it hozirontally
 
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I think it means that they choose new basevectors (##\vec{T}##,##\vec{N}##,##\vec{B}##) and new coordinatesystem to make components of positionvector indebendent of old coordinate system.
By putting by basevectors they mean defining new coordinate system.
Word trihedral indicates that there are 3 basevectors in new coordinatesystem.
Basevectors are not moving, but are not equal in every point of space. I do not know how these basevectors are defined outside trajectory, but the figure on page 50 and this illustration shows how these basevectors are on trajectory.
 
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