Hello. Sounds interesting. I would simply make it swim in wide circles so when it hits a wall, it will slowly turn away from it and continue on. This would save you object sensors and reversing valves. By the way, if the shark's mouth is open when you reverse, won't the leaves get out?
Most, if no all pools have a skimmer built-in so practical market might be limited. I know some folks will buy to see the thing swim around though. I bought one of those automated cleaners a couple of years ago - an Aquabot model. It was the worst $1500 I've ever spent. It did not cleaned the pool like they claimed and it broke after 4 months when used just once a week.
Instead of a shark, I would buy a catfish. A device that goes underwater and brushes the surface. Not just vacuum it, but brush it. Even when the Aquabot did it's best, I always had to brush by hand after it. If you come up with such device, sign me up for one.
JR