friendly piece of advise. I've been through 3 generations of experimental DIY awning designs, and probably have spent over $300 in all trying to do it, not to mention the time. I have all different size tarps and metal round and square tube all over my garage. I really thought my last design was going to be it, and yet, in practicality, it didn't work out the way I had hoped.
I was trying to replicate the hannibal awning for a fraction of the price, then by Gen 3 trying to settle on a supported awning. I came to the painful realization that for the money I already spent, I could have bought an actual supported awning already.
I'm getting an ARB 2500. Save yourself the headache. there are some pieces of kit that lend themselves well to the handy DIYer, and the awning is not one of them.