Metal Sheet; Sheet Metal in English [1] (Metal Plate; SheetMetal in English) is a technical means of automobile repair, in this regard auto sheet metal equal to auto sheet metal repair, refers to the car after a collision to repair the body, that is, in addition to the body Anticorrosive and decorative painting work all the rest of the work outside. Such as the analysis of car body damage, the measurement of car bodies, the shaping of auto bodywork sheet metal, stretch correction, stress relief welding, and assembly and adjustment of auto body accessories. Automobile sheet metal is a kind of processing method for vehicle maintenance, and it is also called cold-made. It is said that if the appearance of the vehicle body is damaged and deformed, it will require the process of sheet metal. The car collision repair has been developed from the original “Pillar welding repair” to the secondary manufacturing of automobile bodies. The repair of collision accident vehicles is no longer a simple knocking of car sheet metal, and the quality of repairs cannot rely on the naked eye to observe the appearance and crevices of vehicles. Maintenance personnel must not only understand the technical parameters of the body and the size of the exterior, but also master the characteristics of the body material, the characteristics of the stress transmission body deformation trend and force points as well as the body of the production process such as welding processes. On the basis of this knowledge, maintenance personnel also rely on advanced measurement tools to determine the direct indirect damage and deformation of the vehicle body through accurate three-dimensional body measurements, as well as the existence of hidden dangers due to the deformation of the body, to develop a complete body. The repair program, and then with the correct repair process and accurate three-dimensional data weighed in the key points, will restore the key points of the body to the original position to restore the damaged body to the factory state.