CG Generalist and TD Alexander Kratinov walks through the process of creating a a simple and dynamically variable pivot rig in Cinema 4D, in this case using the tricky example of animating kinetic energy of a coin rotating and spinning on a table.
The coin spinning scenario is only one instance where a mobile pivot strategy is essential in a rig, certainly this can be animated manually, although less efficiently and less accurate.
Although the pivot is mobile in this example, Alexander further automates the process by automatically placing the pivotal null based on the position and rotation of the animated object and shows how to create the coin spin animation with a bit of Xpresso connections to create a basic coin spinning rig.