A Local Constraint causes all of its constrained joints to have the same displacements for each of the chosen degrees of freedom, taken in the separate joint local coordinate systems. The other degrees of freedom are unaffected. The Local Constraint differs from the rigid-body types of Constraints in that there is no coupling between the rotations and the translations. The Local Constraint is the same as the Equal Constraint if all constrained joints have the same local coordinate system.
This Constraint can be used to:
Model symmetry conditions with respect to a line or a point.
Model displacements constrained by mechanisms.
The constraint must apply to at least two joints to have any effect on the model. These joints may have any arbitrary location in space. The behavior of this constraint is dependent upon the choice of the local coordinate systems of the constrained joints.
Use the following areas on the Local Constraints form to make the appropriate entries:
Constraint Name. Use the default or enter a default name for the constraint being defined.
Constrained DOFs. Choose the degrees of freedom being constrained. These are taken in the local coordinate system of each joint that is assigned this constraint.
If the Define menu > Joint Constraints command was used to access the Local Constraints form, the defined constraint must be assigned to the joints.
See Also
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Access the Local Constraints form as follows:
Click the Define menu > Joint Constraints command to display the Define Constraints form or select the joints to be constrained and click the Assign menu > Joint > Constraints command to display the Define/Assign Constraints form. Then do one of the following:
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