Darboux Vector and Stress Analysis of Centro-Affine Frame

Darboux Vector and Stress Analysis of Centro-Affine Frame

A set of points that corresponds a vector of vector space constructed on a field is called an affine spaceassociated with that vector space. We denote A3 as affine 3-space associated with IR3.The first written sources that can be achieved about affine space curve theory are based on the 1890’s when ErnestoCesaro and Die Schon von Pirondini lived period. From that years to 2000’s there are a some a ` ffine frames used incurve theory. One of them is centro-affine frame.The grup of affine motions special linear transformation consist of volume preserving linear transformations denotedby and comprising diffeomorphisms of that preserve some important invariants such curvaures that in curve theoryas well.In this study, we separated the matrix representing affine frame as symmetric and antismmetric parts by using matrixdemonstration of the centro-affine frame of a curve given in affine 3-space. By making use of antisymmetric part,we obtained the angular velocity vector which is also known as Darboux vector and then we expressed it in theform of linear sum of affine Frenet vectors.On the other hand, by making use of symmetric part, we obtained the normal stresses and shear stress componentsof the stress on the frame of the curve in terms of the affine curvature and affine torsion. Thus we had the opportunityto be able to explane the distinctive geometric features of the affine curvature and affine torsion.Lastly, we made stress analysis of a curve with constant affine curvature and affine torsion in affine 3-space as anexample.

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