The reconfiguration and the capacity of rapid adjustment of automotive welding fixture are the main obstacle to the development cycle and the modified automotive products. A set of reconfigurable fixture has been designed tentatively for a series of car product development. It is consisted of the fixture plate with holes in base stations, the three-dimensional adjustment of bearings and the standard fixtures, which show the character of a quick installation location, easy to adjust, shorten the development cycle and so on.

It’s a key problem in the mechanical field that the machining stress and original stress redistribute in the workpiece when cutting. In the study of this problem, we found a phenomenon of stress wave in the cutting, as in dynamics; Because of the effect of stress wave, the machined workpieces with complicated structure may have more stress focuses, particularly, the aeronautic and astronautic products have many frame structures, the dynamic stress in the machining can undergo many changes because of the structure’s restrain, and leads to the stress focus in the corner of frame. This is the main factor to cause the workpiece distortion. So, the study of this paper is of great value to explain the law of pockety stress in the machined workpiece, and can help to determine reasonable technique to control and adjust the workpiece’s stress, and finally improve the quality of workpieces.