You have my condolences and my sympathy. This is some rough shit.
My first reaction to reading this is that there are two sides to this story. Given how your dad reacted, though, his side of the story doesn't really matter. Lines were crossed, child abuse happened. Nothing you could have put into a text justifies what he did. If you want to go to the police or find a lawyer, I'd imagine there are avenues for your protection open to you. Obviously I am not a lawyer, it would be irresponsible for me to offer you legal advice, or for you to take anything I say as legal advice. But if it's something you want to pursue, I believe these experiences could carry some weight. If nothing else, having a police record of the incident will prove beneficial if you feel you need to take firmer legal action in the future.
You are a person with inalienable legal rights. What you're describing is not only assault, but it's assault of a vulnerable individual (i.e. a child). The fact that he's your father doesn't give him the right. It's not 'discipline,' it's a crime.
All of that being said, I do get the sense that you're giving yourself unhealthy amounts of leeway based on your Asperger's diagnosis. A diagnosis should give you an idea of what you need to do to help yourself function better. It shouldn't be an excuse for bad behavior. "I have X, so I'm just always going to act this way, it can't be helped" is not a helpful or healthy way to think. The world isn't full of social wheelchair ramps for the mentally disabled. You've gotta figure out how to get up those metaphorical stairs, or else you're going to be stuck at the bottom forever complaining about the lack of ramps.
On a more personal note, "Because I said so" is what stupid adults who have an undeserved sense of superiority over children say. It's what someone says when they believe the person they're speaking to is more a burdensome piece of property than they are an individual person. Fuck em'.