Abstract: How to optimize the geometric shape of cultivating components to reduce the working resistance, thus enhancing working efficiency, is always paid much attention by humans beings. The mechanical properties and their discrepancies in different kinds of cultivating components with different soil-engaging surface directrix, after introducing the concept of longitudinal/depth (L/B) ratio, are analyzed and compared with finite element method. The directrix for each cultivating component’s soil-engaging surface is respectively composed of straight line, parabola, cycloid, circular arc and bionic curves including the soil-engaging surface contour line of the claw toes of house mouse, field mouse, mole cricket and cock. Results indicate that the soil-engaging surface directrix and longitudinal/depth ratio are two important factors to affect the working resistance. The curved cultivating components generally possess superior cultivating performance against the straight-line cultivating components with small L/B values (0

Key words: Cultivating component, Directrix, Longitudinal/depth ratio, Soil-engaging surfacx, Working resistance, Adhesive wear, Helical gear drive, Parameters analysis, Quasi-static and dynamic loads, Wear depth