This puppy mastered a 3D-printed wheelchair after being born with only 2 legs

Tumbles, a puppy from Ohio that was born with only two legs, could only get around in fits and starts before scientists at the Ohio University Innovation Center designed him his very own wheelchair. 

The scientists gave him his first wheelchair fitting in early November. Crystal Richmond, a volunteer photographer at Friends of the Shelter Dogs, has been documenting his progress ever since.

Three weeks later, it's fair to say Tumbles has mastered the wheelchair.