To satisfy the requirement of quick modeling and convenient interaction in the process of product sketch design,a three-dimension sketch design technology was proposed,which combined advantages of gesture modeling and outline modeling.

Research on 3D－ sketch based solid modeling;

We often misunderstand the concept of design sketch in the course of learning it, for we don’t understand design sketch correctly.

Research on automobile sketch design based on image cognition model;

In this system,some key problems,wich are the automatic position of the sketch design plane,the projection from the sketch profiles onto the shoe-last surface,the surface trimming based on the projection outlines and the automatic replication of original shoe last surface,have been solved.

By studying the influence digital technology exerted on sketch design,method of presentation,design concept and current situation of Chinese architectural education,the essay analyzed digital technology\'s impact on Chinese architectural field and the problems existed in architectural education.

This paper firstly introduced the importances of the sketching in design,especially in conceptual design,and discussed the specialties of sketching and the shortcomings of traditional CAD systems.