SAP (software)/constraints

Constraints are used to enforce certain types of rigid body behavior.

Body Constraints
Body constraint causes all of of its constrained joints to move together as a three-dimensional rigid body.

Alternative modeling approaches:


 * frame members with very high stiffness properties (use modifiers to adjust the adjust the section properties)
 * linear links with fixed directional properties: this may cause problems when any of the joints are assigned constraints; to prevent problems and instability in this case, directional properties should be assigned high stiffness value instead of being fixed