COSMOSMotion cannot handle part analysis. It can only do
assembly analysis. It can also handle 2D sketches but each each in
motion has to be a sperate part.
From what I understand you are trying to move a point along a
path which has a harmonic motion. This profile will then create
your swept profile for creating the outer boundary of your artery.
This may be a challenging problem for COSMOSMotion to handle.