Mechanical legs are formed by using steel instead of skin and steel brackets instead of bones. The shape is similar to that of human legs. The mechanical leg can not only be used as a transportation tool for people who are inferior to walking, but also can express the sense of robot, machinery and technology. It should be noted that the Apple system is based on the right leg as the prototype in the design of the emoji, while most other systems are based on the left leg as the prototype.
