Form: Assign/Define Constraints
A constraint is a group of joints that are connected. When a constraint is assigned to a joint, the joint becomes a part of the constraint and connects to other joints in the constraint. Constraints can be pre-defined using the Define menu > Joint Constraints command, or they can be defined while assigning them to joints.
Note: More than one constraint can be assigned to a joint. The program will automatically resolve competing constraints. However, do this with caution. Large parts of the model could be rigidly connected together, which may over-constrain (over-stiffen) the structure.
Select a set of joints that will be part of the same constraint. Other types of objects may be selected because they will not be affected by this assignment.
Click the Assign menu > Joint > Constraints command to access the Assign/Define Constraints form.
Constraints display area. Any previously defined constraints are listed in this display area.
To assign a constraint to the selected joints, highlight a constraint in this list to select it and click the OK button.
To remove all constraints assigned to the selected joints, highlight NULL and click the OK button.
Alternatively, use the Choose Constraint Type to Add drop-down list to select a new constraint type and then use the buttons on the form to complete the addition, modification, or deletion of the constraint type. The Add New Constraint, Modify/Show Constraint, and Delete Constraint buttons function as described in the Define Joint Constraints topic.
Example: Assignment of joint constraints is demonstrated in Problem C, Problem N, Problem O and Problem Z.
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