Autodesk inventor tutorial 2018 - inventor constraints explained

Constraints are automatically applied as you sketch. The constraint symbol on the cursor shows the constraint type. Constraints prevent unwanted changes to a feature when dimensions are changed or referenced geometry is moved.

You can add or edit constraints and dimensions to control sketch shape and size. Before you add constraints, study your sketch to decide which are needed. In a 2D sketch, display the Degrees of Freedom glyphs to determine which geometry is unconstrained, partially constrained, or fully constrained.

2D and 3D sketch geometry to include in constraint

In addition to geometry, you create in the sketch, you can select visible model edges and vertices for inclusion in a constraint. You can select a point at the virtual intersection of sketch elements.

In 2D sketches, the selected curves and vertices are automatically projected onto the sketch plane. Alternatively, you can select geometry and use Project Geometry to project it onto the sketch plane before applying constraints.

Tips for using constraints :-

Click the constraint command you want to use, and then:
1) Use inferred constraints to position geometry as you sketch. When a sketch command is active, move the cursor to show constraint symbols that indicate relationships to existing geometry. For example, a parallel constraint symbol appears when the new line is parallel to an existing line.
2) Brush the cursor along the line or curve you want to constrain to, then move the cursor into the approximate position. In cases where more than one constraint is possible, this technique overrides a default constraint in favor of the constraint you selected.
3) The order in which geometry is selected does not affect the results of a constraint operation. However, the presence of other constraints can affect further constraint application. Geometry with fewer constraints is repositioned or resized. If a constraint cannot be applied, a warning dialog box is displayed.
4) Constrain to an existing model or sketch geometry.

Note: To apply the same constraint to multiple curves, select the curves you want to constrain, then click a constraint command.