Abstract. Optimum energy consumption and prevention of energy losses are important issues
in various fields including agricultural engineering. Mower is one of the agricultural
machineries that can waste too much energy if does not function properly. In this study, the
performance of a single disc rotary mower was studied and optimized by measurement of
cutting quality of the stem cross section (cutting quality) as a criterion. Taguchi L9 orthogonal
arrays table was used to find the optimum combination of parameters to reach the best cutting
quality. The selected factors are: mower forward velocity, disc rotational speed, number of disc
blades and shape of the blade, each one at 3 different levels. To measure the quality of the cut
hay, ENVI image processing software was used. This software has been developed for texture
qualification of image processing studies. The texture of the images captured from the cross
section of cut stems by the mower is analyzed according to the reflected wavelength from the
surface. ENVI software assigns a number to the cutting quality of each stem, which is called
eigenvalue. The results then were imported to the orthogonal arrays table of the Taguchi
method. Minitab software was used to calculate the optimal level of the studied variables.
Analysis of the results show that 886 rpm of the disc rotational speed, 1m s-1 of the forward
speed, four symmetrical triangular serrated blades on the mower disc are the optimal values of
the factors and offer the highest cutting quality. The optimum value predicted by the Taguchi
method was approved by an experimental method.