The Q500 is a Beast, and wider than the average person back. Hardshell backpack would be cumbersome in width and depth as well as unbalanced weight (center of gravity going way out there).
Choose the right tool for the job. The Q500 is not something that I would pack on a mountain climbing trip, or an extended hike through a dense forest just to take pictures.
At best, just hit anyplace that sells backpacks and get one that will allow the landing gear to straddle it, a couple of bungee cords, or some paracord and tie it down to the pack. If you are worried about debris and elements, put it in a pillowcase or other sack treated to repel water first, then strap it down.
Here is what a member on another forum does with his, and he goes in some pretty interesting places.