what is a spine in CATIA??

The use of a spine curve in variable filleting, swept and lofted surfaces is generally used as a guide curve to orient the cross-section of the feature as it moves along its path.

spine...used in complex geometries..in case of a guided spine .it is the successive addition of the points on the line of the intersection of the plane normal to a tangent at a point on the first guide and a plane normal to a tangent of the first one projected on the second guide tangent .....this photo explains ..
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