Kinematic Constraints

Kinematic constraints are equations that control the motion of solids, faces, edges, or points. Add a Prescribed Displacement constraint to enter expressions for constraints. You can define the equations using predefined coordinate systems as well as custom coordinate systems. Special constraints, for instance to keep an edge of body straight or to make a boundary rotate, require such constraint equations.


	For an example showing how to force a boundary to remain plane, but still allow it to translate in its normal direction, see Thermo-Mechanical Analysis of a Surface-Mounted Resistor: Application Library path Structural_Mechanics_Module/Thermal-Structure_Interaction/surface_resistor.


	In the 3D and 2D Solid Mechanics interfaces and in the Shell interface there is a special constraint called a Rigid Connector. A rigid connector is applied to one or more boundaries or edges and force them to behave as connected to a common rigid body. The rigid connector can be given prescribed displacements and rotations and thus simplifies the realization of some constraints.