Why are the helmets made round?
Round helmet can maximize the impact of single impact, but also has the strongest resistance to pressure. Moreover, the round helmet is the most beautiful helmet from the outside. The shape of the helmet is a thin shell like structure that is arched outwards. It is not easy to deform when subjected to external force. 2., the cushion of the soft wall will also play a buffer role, hemispheric helmet is the most solid.
Safety helmet use with construction workers as an example, if there is a brick falling from a height, just hit the safety helmet, because the action of gravity acceleration, so the safety helmet by great force and has great destructive power, but the smooth hemispherical shell can concentrate the impact force along the spherical average dispersion at the same time, from the elastic pad object along the cap and can continue to receive buffer, so that the pressure head and take responsibility for the impact is greatly reduced. According to scientific speculation, the dispersion and buffering effect of the helmet can reduce the impact to around 5/6, so that the head can be well protected. Therefore, construction sites and mines are strictly required to enter the construction site workers wear helmets. In the same way, a motorcyclist's helmet can greatly reduce the impact of the driver's head in the event of a traffic accident, thereby reducing casualties.
A solid object, in addition to the strength of material and its outside, more important point is its appearance, according to the best shape that can withstand external force is a spherical convex surface, this is due to the convex surface will be applied pressure distribution along the convex surface to open, and the the stress is uniform, which makes hemispherical has great stiffness.
