The definition of relative orientation of two vector pairs <i>A</i> and <i>B</i>.

Abstract

<p> is the direction vector from <i>A</i> to <i>B</i>. is the direction vector from <i>B</i> to <i>A</i>. Ω is the torsion angle between plane <i>A₁AB</i> and plane <i>ABB₁</i>.</p