This is a picture of a cat in a giant hamster ball (which I guess is actually a regular size cat ball) with a BB-8 head on top. I'm going to go out on a limb here and assume the head doesn't stay balanced on top if the cat runs inside the thing. I'm going to assume all of this came together solely to take this picture. Mission accomplished! Now toss some catnip in that ball and lets see what happens. SPOILER: pure Youtube gold.
Thanks to Linc, who tried to tell me this is really how BB-8 was operated in the movie which I knew was a lie because cats never do what you tell them to.