Research Of Surface Development Method Based On B-Spline And Geometrical Mapping

As a standard production process, the workpiece pressing forming technology plays an important role in many manufacture fields. As an important pressing forming parameter, the development dimension of the blank workpiece surface is the precondition of analyzing the pressing forming degree, designing technics and establishing technics flow. Whether the development dimension of the blank workpiece is accurate affects the validity of the blank workpiece roughcast dimension. Furthermore it will affect the whole technics flow. The approximate development of the blank workpiece undevelopable surfaces have great theory and practice significance to perfect pressing forming technology.The main content and result of this paper are as follows:Firstly, the experimental study on the expression of the undevelopable surface. The B-spline discrete method and de Boor algorithms are used to express the complex curves with quadrangled gridding in this paper.Secondly, the experimental study on the development of the undevelopable surface. Based on the basic theory and principle of the development of undevelopable surface, the development method put forward is based on the rules of the geometrical mapping and the invariable area. The development errors are analyzed theoretically, and several factors on the development of undevelopable surface are enumerated.Thirdly, the experimental study and development on the computer aided curve surface development software. Based on Mechanical Desktop(MDT) and VC++, this software uses the knowledge of graphics and the technique of parameter auto-partition and boundary disposal, and makes the secondary development on Mechanical Desktop(MDT).