D. Guglev, M. Vassileva Abstract. The present theoretical research of a vertical rotational soil-cultivating organ with two knives and active drive offers a method for defining the following parametres of a soil chip: cross-sectional area, length of the curve of cutting, circumference

D. Guglev Abstract. Experimental research of rotary harrow Arterra Grip 400 was carried out to determine the value of vertical rotors’ kinematic parameter which provides the necessary soil’s crushing to pieces depending on the constructive parameters and the harrows duty.