Mark Hamill shared the following in an interview with Yahoo! Movies:
They never cease to amaze me with what they’re able to come up with, you know? I said, “How are you ever gonna top R2-D2, the most adorable droid in movie history?” And then they have this new one. I can’t even tell you his name, but you saw it in the trailer. [Editor’s note: the name of the droid has been revealed as BB-8.] And when they were demonstrating how they did this thing, live on set — because it’s not CGI, that’s a live prop — I was just amazed. They let me play around with it. [Laughs] I was running it all around at the creature shop up in Pinewood. I’m telling you, it’s an absolute delight. And not having thought that I’d ever go back there, to go back into that world, is just – I get the chills. It’s just so much fun.
Recall that Disney CEO Bob Iger recently emphasised the use of real props and sets for The Force Awakens. Lucasfilm and Abrams seem determined to give the actors a believable, tangible world for their characters to inhabit. If the actors believe the world is real, the audience believe it, too.
On a side-note, it’s so great to hear of Hamill’s delight at returning to Star Wars. It’s a day that we never thought would arrive… yet here we are.