Check of singularity
Check of singularity brings to user possibility to check if his model is instable and/or has not some translations or rotations. Not connected members are also detected. Check is also suitable to use for detection of problem with cross-links.
Check is performed after unsuccessful calculation and user can interactively see shape of instability (translations, rotations) of structure or parts of structure. Then user can easily repair problem which he saw in animation window.
The theory which is behind this check is based on computation of so called zero Eigen-value and detection of corresponding Eigen-shape.