Optimization of design parameters affecting the performance of the chopping unit in maize silage machines using the taguchi design of experiments method

The chopping units used in corn silage machines operate through the interaction of fixed and rotating knives, and the accurate determination of the design parameters of these units directly influences machine performance and energy efficiency. The fact that agricultural harvesting operations must be conducted within short time periods and that experimental studies are dependent on natural conditions makes it difficult to obtain reliable results in this field. Therefore, the Taguchi experimental design method, which produces statistically strong and valid results with fewer experiments, was preferred in this thesis. The experimental phase of the research was carried out on a small-scale chopper prototype that was developed for this purpose. The investigated parameters included the distance between knives, the angle between knives, cutting speed, and the number of corn stalks processed by the unit. The experiments were planned using the L27 orthogonal array, and force measurements were performed based on the maximum force values recorded via a dynamometer. The data were analyzed using the Minitab 22.3 software package and evaluated according to the "smaller-is-better" criterion. According to the findings, the optimum parameter values for the chopper unit design were determined as a knife distance of 1 mm, a knife angle of 12˚, a cutting speed of 3,5 m/s, and two corn stalks processed during chopping. The analyses revealed that the parameters affecting the cutting force the most were, respectively; the number of corn stalks processed, the cutting speed, and the knife angle. This thesis was conducted on the developed prototype, and it is recommended that experimental studies be carried out on real-scale silage machines to increase the validity of the findings. In future works, more comprehensive research is planned on real-scale silage machines, taking into account different types of parameters. Keywords: Chopper unit design in silage machines, signal-to-noise ratio (S/N), Taguchi method, design of experiments, quality control 2025, 66 pages