Lesson 3 - Tyre Controls

The first part of the rigging process on the car is to make sure everything is named in a way that an end user would recognise the pieces. The end user can then use the outliner to quickly select the pieces they need should they have to.

Clear naming scheme allows users to know each groups contents.

 

After naming the groups, create three controllers using the CV Curve tool. One will control suspension on each tyre (4 total), one controls the steering on the front two tyres (1 total) and the last will control the rotation of the front and back tyres (2 total). Try to make the curves look like the action they will be doing as shown below:

Don't forget to freeze transforms, delete history and center pivots.

Be sure that the pivot for the wheel group are at the center of the wheel (on the axle). Using two orient constraints on a single tyre overwrites the previous orient therefore the workflow for the wheel is a little different. First, select your steering controller followed by the tyre so both are highlighted. Then in the Constrain menu, add a normal 'Orient' constraint in the 'Y' axis. Be sure that Maintain Offset is ticked.

The wheel should now turn when the controller is rotated in the Y axis. Next, select the drive controller and then the wheel again. This time use a 'Parent' constraint. This allows you to use two orients and the same time. Parent the rotation to the 'X' axis and untick all other Translate and Rotation boxes.

The wheel can now rotate and turn without overlapping each other. The last stage is to attach a Point constraint to the suspension. Select the suspension control and then the wheel and attach a 'Point' constraint in the 'Y' axis. The tyre can now move up and down when you move the controller.

The final stage of the tyres is to limit the controller. This stops it moving after it reaches a certain point. To limit the controls movement, go to the attribute editor and look in 'Limit Information'. Find the action needed to move the controller (In the example I use the steering controller meaning I need to limit the rotation) and enter 'Min/Max' values. Current should be set to 0.

Now if you try to rotate the controller past 45 degrees either way, the controller will stop and the wheels won't move past it either. Later we'll lock the axis so they can only be moved in the desired direction.

Repeat the rotation process for the 2nd front tyre and put the suspension and drive on the rear tyres.