After discussion with the Game Design Committee, we are issuing the following answer.
The VEX Robotics Design System is intended to be a mobile robotics design platform. As such, a VEX robot, for VRC purposes, has the following subsystems:
**Subsystem 1: **Mobile robotic base including wheels, tracks, legs, or any other mechanism that allows the robot to navigate the majority of the flat playing field surface.
**Subsystem 2: **Power and control system that includes a VEX legal battery, VEX control system, and associated motors for the mobile robotic base.
**Subsystem 3: **Additional mechanisms (and associated motors) that allow manipulation of game objects or navigation of field obstacles.
Given the above definitions, a minimum robot for use in any VRC event (including skills challenges) must consist of 1 and 2 above. Thus if you are swapping out an entire subsystem of either item 1 or 2, you have now created a second robot and are no longer legal.
We’re trying to make the best common sense ruling possible on this topic, without creating any confusing and hard to enforce rules. Hopefully this clears up the issue in the way that would be expected by participants.