No. 'Clone trooper' in itself is not copyrighted, but it is when affiliated with the Star Wars characters. Even if you're making a Star Wars brickfilm for YouTube, you're fine monetising it. It's only if you came to sell it commercially or enter it into festivals that you might run aground.

"Nothing goes down 'less I'm involved. No nuggets. No onion rings. No nothin'. A cheeseburger gets sold in the park, I want in! You got fat while we starved on the streets...now it's my turn!" -Harley Morenstein

You also should look into copyright law when considered a "parody" a little bit of lawyer-think will tell you that with parody law and fair use you can get away with a lot artistically!

As for Youtube monetizing, you can get away with just about anything as long as you don't use the actual music/sounds. No worries there. It's the festivals that you need to worry about. You can't enter a festival with a Star Wars themed short, and using a full clone trooper as anything but a tiny cameo may also be risky. Not that I'm an expert, mind you.

Use of the torsos on sci-fi soldiers should be fine, but the helmets are instantly recognizable and best not used at all.
If you're wanting to sell your own video, it has to be your own, not based on Star Wars or using any of it's characters/locations.

For festivals, at best they will refuse to accept it, which is bad enough.

And yes, there's the whole loophole of doing a parody, but most festivals ban copyrighted content anyway to encourage more original films.