I’ve been volunteering with the local FIRST Robotics team. A small group of us came up with a drive module for the robots that allows the maintenance team to make very quick repairs to the robot. In the event of drive motor, gearbox or wheel failure we’ve managed to reduce the repair time from 20 minutes or so to less than one minute. I modeled what we proposed in SketchUp.
There are a number of different configurations for the base that all use the same module and the modules can be built with different wheels to suit the needs of the robot. Shown with Omni wheels.