This present invention is a personal mobility device for transporting a person over different surfaces and obstacles. This invention comprises novel technology that can be used for next-generation motorized wheelchairs that enable people to travel outside during winter months, to go “off-road,” and to travel up and down staircases independently. This invention features shape-changing wheels that change shape to travel more effectively on different surfaces and obstacles. The shape of a shape-changing wheel is changed by the motorized rotation of at least two rotating members that are part of the shape-changing wheel. Rotation of these rotating members into a first configuration causes the ground-contacting perimeter of the wheel to be circular. Rotation of these rotating members into a second configuration causes the ground-contacting perimeter of the wheel to be non-circular.
