Conference article

The MultiBody package of the Modelica Standard Library (MSL) contains a Prismatic Joint model with two Frame connectors where one frame can move with respect to the other along a direction n. This can be viewed as that the second frame can move along a straight line fixed in the first frame. In this work a constraint is developed where this line is replaced by some curve described by some suitable geometry: A Pointto-Curve (PtCv) constraint. It turns out that there are several options to define the orientation of the second frame with respect to the first one. Additional degrees of freedom are possible. These ideas can be applied to 2D: A Point-to-Surface (PtSf) constraint . PtCv and PtSf constraints seem to be suitable building blocks for higher order constraints: Curve-to-Curve (CvCv) resp. Surface-to-Surface (SfSf) constraints. As a byproduct there are some Joint models not yet available in the MSL at all or not in that form; like an elementary Cylindrical joint.

Point-to-curve contact; osculating circle; point-to-surface contact