How can I tie 2 surfaces together, but only w.r.t. 1 specific DoF? Moreover, this 1 DoF is w.r.t. a non-standard coordinate system, i.e. as a result of *TRANSFORM.
Example: frictionless “contact” of a bolt in a borehole. The pin is allowed to freely move in the direction of its main axis and to rotate about it, but it must follow the borehole for all other possible movements.