The Mechanical Model Of Facial Expression Wrinkles

With the ever-increasing power of computer graphics and hardware, it is now possible to produce high level image with the computer. Animation hasn't been an unfamiliar word. Research on the animation of the human facial expression is a very challenging topic in computer graphics. It involves the knowledge of mathematics, physics, mechanics, physiology, computer science and psychology etc. In computer facial animation, how to simulate the wrinkles is a difficult task. Skin and muscle are responsible in determining and providing the facial wrinkles. The physiological structure of skin and the face were introduced. Some physiological reasons which affected the wrinkles were stated. It put forward a mechanical model to simulate the forehead wrinkles, crow's feet and wrinkles of corners of the mouth. The forehead wrinkles of facial skin according to the buckling of rectangle plate in elastic substrate and sandwich panel were simulated. The crow's feet and wrinkles of corners of the mouth were simulated by the annular plate. The wavelength and amplitude of the buckling deformation were deduced. It can be concluded that the Young's modulus of epidermis, dermis and hypodermis tissues had great effect on the wavelength and amplitude. With the elasticity of dermis and hypodermis increased, the wrinkle will be weaken. This thesis put forward the mechanical model of facial expression wrinkles, which provided the base for simulating the wrinkles of facial expression animation.