You can see the lens inside one of R2's "eyes". The projection is controlled by remote control, and it runs off of its own power source; it doesn't drain power from R2's other systems.
The lens has to remain perfectly still and centered on the eye, no matter how bumpy the terrain may be. Holding the lens steady proved to be a challenge inside the curved, bottomless dome. I had to attach a metal plate and some support arms to lock the lens in place.
I think it's a great effect and the perfect addition to R2. Since it is now able to project an entire presentation on its own, including the accompanying sound, R2 is much more than a visual demonstration of computer programming and circuit design. It can now teach you how to build itself!