The automotive differential is an ingenious mechanism which enables the two driven wheels of a car to operate at different speeds when the driving conditions call for it, such as during a turn. All automobiles employ various types of differentials.
In this tutorial, you will learn how to design the most basic kind, the open differential, in Blender. The workhorse of a differential mechanism is a bevel gear. Modeling a bevel gear drive is described in detail in Tutorial #3. We have recently enhanced the Bevel Gear Calculator, used by both tutorials, with a Python script generator which greatly simplifies the design of a bevel gear pair.
This tutorial will also show you how to test the differential mechanism in both the straight-motion and turning modes of operation using Blender's Rigid Body Physics engine.
The end result of this tutorial, a .blend file containing a functional automotive differential mechanism, can be downloaded via the link below.
Related: Bevel Gear Calculator