Cart for physically-challenged
A vehicle is designed which can be propelled by wiggling the front steering wheel, attached to two pivoting wheels touching the ground. It harnesses natural forces of inertia, centrifugal force, gravity, and friction in order to drive the car forward and backward. It does not require a power source such as battery, fuel, pedal, or gears. Instead, it simply runs on the person’s ability to wiggle the steering wheel. It can be operated indoors and/or outdoors, though it works best on a smooth, flat surface.
Link: The aerodynamic shape gives better speed and more comfort to the user
it has less ground clearance
This device is also comparatively cheaper and durable than other vehicles and wheelchair available for the handicapped
Problem Scale: Around the world