when did the self balancing scooter come out
Self-balancing scooter Invented in its current form in early 2013, the device is the subject of complex patent disputes. Volume manufacture started in China in 2014 and early units were prone to catch fire due to an overheating battery which resulted in product recalls in 2016, including one of 500,000 units sold in the United States from 8 manufacturers.
Wheel and axle The wheel and axle can be viewed as a version of the lever, with a drive force applied tangentially to the perimeter of the wheel and a load force applied to the axle, respectively, that are balanced around the hinge which is the fulcrum. The mechanical advantage of the wheel and axle is the ratio of the distances from the fulcrum to the applied loads, or what is the same thing the ratio of the diameter of the wheel and axle.[2] A major application is in wheeled vehicles, in which the wheel and axle are used to reduce friction of the moving vehicle with the ground. Other examples of devices which use the wheel and axle are capstans, belt drives and gears.