I found out that the running gag of Andy comedically waking Barney up from his naps was inspired by a real-life thing. Due to the high comedic energy needed all of Don Knotts scenes for Barney Fife would usually record the high comedic scenes early in the morning (5am to 8am) and then he'd go take a nap on a cot/bed backstage while other scenes were being shot until he was needed for the outdoor scenes. What Griffith used to do would be when it came time to wake him would drop something heavy (old film reels or something similar) that would cause Don to jump out of bed and stand at attention. After seeing this a few times, the filmmakers started working "Andy wakes Barney" into the script.

Didn't know that, that's cool how they used it in the show.