I'm curious to find out different methods that are used for automobile rigging, particularly auto-rotating wheels.
When rigging a car, a "nifty" feature to add is when you translate the master controller, the wheels "auto-rotate". Now after working out what the radius of the wheels are and how many units does the controller have to translate to get one full rotation the problem comes in, when you start rotating the master controller the wheels start flipping weirdly. A method that counters that is explained in this video: https://www.youtube.com/watch?v=QpDc93br3dM basically using vectors for the wheels to aim at. This method works really well, but I am curious to know if a similar result can be achieved without the use of expressions?