Research On Technology Of 3D Sketching For Product Conceptual Design

Innovation has become one of the most important aspects in production design. It mostly concentrates on conceptual design phase. In this phase, sketching design, as designers' basic means for expression and communication, is not only the important medium for graphics thinking during innovation exploring, but also the significant step of changing design into visualize in the design activities. Meanwhile, traditional CAD tools are mainly used during specific design phase and cannot fulfill the demands of conceptual design.Based on the characteristics of sketching, this dissertation makes a systematic research on computer supported 3D sketching techniques, including the related work of the computer supported 3D sketching techniques, pen-based gesture interface for 3D sketching design, sketch-based 3D modeling and model editing. Finally, a 3D sketching system is implemented. Specifically following contributions have been made:1. Through the application of the gesture-based interaction techniques, the complex interaction operations are replaced by simple strokes. Based on the matrix-coding gesture recognition, matching algorithm which combines local matching with rule matching is introduced. It not only improves the recognition efficiency but also enhances the freedom of the gestures.2. Silhouette-based modeling and modeling based on characteristic gestures are implemented. The modeling algorithms are improved.3. A 3D sketching prototype system is implemented...