Solve this simple clothes dryer problem

OK, mechanical engineers! Solve this simple clothes dryer problem. An electric clothes dryer with its rotating drum does a good job of drying most clothing. But sheets and blankets tend to roll up in balls. While they may get dry, they don't get the lint and dust knocked off the areas inside the ball. What are some ideas for a better design?

I've often wondered whether a dryer whose drum reversed direction periodically would still roll clothes up in a ball. Anyone know the answer to that?