Why do I always seem to mess up in my father's eyes?

My father age 46, evidently thinks of himself as some sort of demigod such as Hercules or something to that effect. To where he does no wrong at all and he has the smarts of a college mathmatics scholar which he does not at all, sure he's kind of smart but now really. He likes coming around the house after work like he's just dragged a freakin airplane across the Mojave Dessert. When its nowhere near that, and he complains at every little thing i say or do, i wont even get an attitude with him or anything and try and show respect even though im being bombarded with either cursing or how im going to be grounded. I dont know what to do, im about to turn 17 and really wish 18 was here. He provides the main source of income in the house and if i leave i wont be able to afford it, college sounds amazing and id love to get away from it all and stay in a dorm. But for this next year i see it being a constant hell for me where i get in trouble for being a teenager from this day and age where we have cell phones and electronics, and he just doesnt seem to understand, hes on medication for being angry and such cuz since his sister died when i was a baby my mom says hes never been exactly the same, i have a little bro too and my dad i swear has a calendar set to where he has weekly intervals on which to chew out the two of us. I really need some help and i dont want that stupid crap saying oh toughen up its not your dads fault hes an ***?!?! yeah it kind of is so please just help im sick of it and its stressing me out cuz if i try and talk to him about he'll just denie it even happened pretty much, so frustrating....help