Gear tooth surfaces are not absolutely smooth

but have roughness and waviness produced with all machining techniques.For the grinded gear tooth surface

its surface roughness is anisotropic in the direction of machining path and the perpendicular direction of the machining path.However

the available fractal simulation of two dimensional rough surface profile curves and three-dimensional rough surfaces based on W-M function are used to simulate isotropic rough surfaces.A method of superposition of two W-M functions for the fractal simulation of gear teeth surfaces with anisotropic textures is presented.Simulation results show that

rough surfaces with different fractal dimensions and different feature scaling constants in two directions can be well simulated with this method

and the gear tooth surface textures can be effectively controlled with the changes of the fractal dimension and feature scaling constant.