The Identification Of Gesture Commands In AutoSketch

The procedure of the automotive styling is a process which starts from2D sketch to3D digital model. However, the traditional CAD (Computer Aided Design) systems do not sup-port this process coherently. The commands are used in the traditional CAD systems mostly by toolbar, mouse, and keyboard. As a result, the stylists have to move the mouse, click the toolbar again and again, and construct models one by one. The efficiency of the design is very low. The stylists couldn’t get the3D digital model through putting2D sketches into3D designing software directly, and also couldn’t draw freely in3D CAD system as on the paper. Therefore, the AutoSketch will be an innovative assisted styling tool only when it provides the stylist with a natural and efficient user interface and gestures command easy to be re-membered and handled.The paper has investigated the differences between AutoSketch and the traditional CAD systems, analyzed the related literatures from domestic and aboard, and summarized the techniques and theoretical methods of the relevant prototype systems. It has compared the differences between two methods of extracting features from a single stroke, and proposed to extract the features from a single stroke based on the vector method. The paper has designed a group of gesture commands, set the thresholds to restrain and distinguish one gesture command from the others, and improved the efficiency of identification.The purpose of the AutoSketch, a3D sketching system for automotive styling, aims to combine the2D sketching with3D modeling perfectly, meanwhile, help the stylist drawing more faster when they use the AutoSketch to avoid the stylists moving the mouse, and click-ing the toolbar repeatedly. It will be very useful for stimulating inspiration and improving the creative design. As the most important component in AutoSketch system and the most im-portant academic achievement in this paper, the stylist can draw gestures command directly on screen by hands. It’s different from the way of sending out the commands in the tradi-tional CAD systems. The paper has studied the sketching with gesture commands in order to speed up the design review process, and reduce the development peiod of automotive styling. It is very useful for a CAD system with the gesture commands, and also very useful for en- hancing the quality and efficiency of the creative design.This paper aims to study the identification of gesture commands. It includes the five phases:· Firstly, the features have been extracted from a single stroke based on the vector method, and listed out the necessary features, which can be used by the identifica-tion of the gesture commands to restrain and distinguish one gesture command from the others.· Secondly, the data points have been diluted to make a single stroke smooth by the algorithm of Douglas Peucker. The significant feature points are retained and the rest are deleted.· Thirdly, the paper has analyzed the ways of developing gesture commands from domestic and aboard literatures, and compared the advantages and disadvantages of the single-stroke gestures and the multi-stroke gestures. In order to accord with the thinking habits of stylists, some gestures have been defined and prototyped, such as None, Origin, Ok, Undo, Redo, Erase, Smooth, Break, Span, and Fillet, which can be sketched out.· Fourthly, the paper has investigated the thresholds to restrain and distinguish one gesture command from the others, and determined the accuracy of parameters based on the experimental analysis, and improved the efficiency of identification.· Finally, the gesture commands have been applied in AutoSketch, The tests show that the gesture commands have better performance in real-time identification, shorter time and higher efficiency.