FFF.1.2.4.1 Positioner Movement in the Isocenter Coordinate System

The positioner coordinate system is defined in section C.8.19.6.13.1.2 of PS 3.3 where the positioner angles are represented as (Ap 1 , Ap 2 , Ap 3 ).

A point (P Xp , P Yp , P Zp ) in the positioner coordinate system can be expressed as a point (P X , P Y , P Z ) in the Isocenter coordinate system by applying the following transformation:

(P X , P Y , P Z ) T = (R 2 . R 1 ) T . ( R 3 T . (P Xp , P Yp , P Zp ) T )

And inversely, a point (P X , P Y , P Z ) in the Isocenter coordinate system can be expressed as a point (P Xp , P Yp , P Zp ) in the positioner coordinate system by applying the following transformation:

(P Xp , P Yp , P Zp ) T = R 3 . ( (R 2 . R 1 ) . (P X , P Y , P Z ) T )

Where R 1 , R 2 and R 3 are defined as follows:

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