Partial Deformation Encryption Method for CAD Model in Collaborative Design

To enhance the security of CAD model in collaborative design, firstly, the architecture of sensitive information protection is proposed based on partial deformation of CAD model. Sketch parameters are transformed to deform the shape of CAD model to hide original model information. Then, an encryption matrix method is presented to encrypt control points of sketch by using the matrix as the encryption key. Further, in order to control the deformation tendency of encrypted model, a Free Form Deformation（FFD） based encryption method for sketch is introduced from geometry computation into feature based CAD systems. This method applies an encryption lattice to encrypt sketch. Finally some case studies were made to demonstrate the method.