Adding FixitiesFirst, what's a fixity? A fixity tells the edges of your structure if they are "fixed." For example, if you put a fixity in the bottom left corner of the dam, that corner cannot move (it is fixed). Fixities are applied to the nodes (see the question on nodes) on the outside edges of the model.Click on Add Fixities. You have three choices: Fix X Only, Fix Y Only, and Fix Both. Pick one of these choices then click on the points of your structure where you want to apply this fixity. A red square will show up on the points you have clicked.
Fix X Only: can't move in the X-direction
(left and right) There is a small XY map below the applet to remind you of the positive X and Y directions. Click on Done to move on. |