Materials include ABS engineering plastics, FRP and carbon fiber. ABS is the worst, FRP is in the middle, light and hard, and carbon fiber is the best, light and hard, but the price is the most expensive.

The shell of the helmet is made of high-strength materials, such as metal, engineering plastics, Kevlar fiber, etc. And most of the impact force is absorbed through its deformation.

Although there are many kinds of vehicles, their structures are similar. This should be said to be the credit of standardization and the need of large-scale production line. With the development of society, the progress of science and technology and the change of demand, the appearance of railway vehicles has also begun to change, especially the passenger cars are no longer the same old faces. However, their basic structure has not changed obviously, but the specific parts have more scientific and advanced structural design.

Generally speaking, the basic structure of a vehicle consists of five parts: body, underframe, running gear, coupler buffer device and braking device.

The car body is the part of the vehicle carrying goods or passengers, and it is also the basis for installing and connecting other parts of the vehicle. The bodies of early vehicles were mostly wooden structures, supplemented by steel plates and bow bars. Modern automobile body is mainly steel structure or light metal structure.