本研究主要是發展一套汽車造型設計系統，其原理乃是利用機構學中，凸輪運動曲線方程式參數化特性，來進行汽車造型設計，以協助設計師突破構想發展之瓶頸。機構學在學術界的發展歷史悠久，在史上已有記載的「天工開物」，可說是機構學的史書。但在發展已久的學門中，如何創新原有的學理技術，是傳統學門中重要的課題。本文利用傳統之凸輪運動曲線方程式，應用於汽車造型設計，在文獻中尚未發現相關研究，且為傳統學門中另闢一片天空。
凸輪運動曲線方程式之特性，具有參數控制之優點，藉由少量的特徵點資料即可將凸輪運動曲線表現出來，本研究就此優勢為出發點，且結合逆向工程的觀念，利用3D SCAN掃描原有之汽車模型，獲得一點群資料且從中擷取特徵點資料，並輸入至模擬系統中重新設計，而藉此少量的控制點，即可對一汽車造型加以描述。當設計師要改變造型形狀時，只需要變更少量之曲線控制點，即可修改至設計師所構想的汽車曲面造型。同時，本研究也將凸輪曲線中的位移、速度、加速度等運動曲線進行合成，以產生較平滑之造型曲線。除此之外，設計師也可將兩組不同汽車造型的控制點進行混成，自動產生具有兩種汽車造型特徵的車型，以擴展設計師的想像空間。
本研究藉由凸輪運動曲線方程式，應用於汽車造型設計之領域上，不僅可協助設計師有效率地進行汽車造型的構想發展，且可提昇業界在汽車造型設計上之技術能力。所研發的模擬系統，利用功能強大之OpenGL函式庫，提供使用者便利的視覺效果，且提供通用之點資料輸出格式，提高軟體的相容性。藉由此模擬系統，不僅對汽車造型有所貢獻，也可以利用此模擬系統，應用於其他產品造型上之設計，對於工業設計有其重要之意義與貢獻。

The goal of this research is to develop an automobile styling design system, which uses the characteristic of cam motion equations in mechanisms, to help industrial designers in concept development stages. Mechanisms in mechanical engineering have been studied for a long time. However, how to make some innovative ideas using the ancient technology and knowledge becomes a challenge for researchers. The papers related to the automobile styling design using cam motion equations have not been discovered in the field of mechanical design or industrial design. This creative idea might arouse the curiosity for those who are interested in automobile styling design or consumer product styling design.
One of the distinguish features of this work is that the contour of an automobile can be represented by the cam motion equations using small amount of control points, for instance, 21 control points in the demonstration examples. Furthermore, the reverse engineering process is performed to scan several automobile replicas using 3D scanner to retrieve the control points from the scanned data. The set of the control points is input into the simulation system to redesign the contour of the automobile model. Designers can modify the shape of the model by altering the positions of the control points. The second distinguish feature of this work is that the position, velocity and acceleration of cam motion equations are composed to make a new contour of the model more smoothly. Besides, the morphing between two automobile models is performed by blending two sets of control points linearly. The characteristics of both automobile models can be preserved and more styling models can be generated to inspire designers in the concept design stage.
This is the first paper to discuss the possibility of using the cam motion equations in automobile styling design, which not only help designers in preliminary design stage effectively, but also improve the quality in the automobile styling design. This simulation system is programmed using OpenGL application programming interface, which provides a user-friendly visual environment. The obtained results can be exported to another commercialized CAD system using IBL format to create a 3D automobile model in rendered form. Nevertheless, the simulation system not only can be used for automobile design but also can be used for other commercial product design. The contribution of this work can be utilized in the future for both mechanical design and industrial design research fields.

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