The principle of kinetic energy is that anti-collision pads generally consist of an end, energy absorbing materials, two side guard beams, a transverse partition, and a back support. After a vehicle collides with the anti-collision pad, the energy of the collision vehicle is absorbed through the deformation of the end and the energy absorbing materials, while the back support is used to resist the vehicle's impact. Energy absorbing materials are generally foam materials or rubber materials. The crash pad based on this principle has a good energy absorption effect and guidance function for front and side collision of vehicles. After the collision, the main parts of the system can be reused, and the maintenance is convenient and fast with low cost. The disadvantage is that the initial installation is slightly complicated and the cost is high.
The principle of conservation of momentum is generally composed of sand filled or water filled anti-collision tubes (piers) of different masses arranged in a certain order. After the vehicle collides with the anti-collision pad, the momentum of the vehicle is sequentially transmitted to the anti-collision tube, causing the speed of the vehicle and the anti-collision tube to decrease in sequence, and finally reducing the speed of the vehicle to below 15km/h.
