# Evaluation of an Optical Sorter Effectiveness in Separating Maize Seeds Intended for Sowing
## 2 Materials and Methods
### Experimental Design  
Two different methodologies were chosen to test the technological flow, which involved the controlled contamination of the seeds and the evaluation of the optical separation outcomes. The first approach consisted of feeding the sorter via an elevator in an indirect manner, whereas the second approach involved feeding the sorter directly. The purpose of using a range of techniques was to precisely determine where the issue that resulted in the appearance of non-compliant outcomes occurred in the flow. Independent and Direct Feeding of the Optical Sorter  
In order to supply the processing flow with the raw material that needs to be processed, in the first experimental design, the seeds were lifted using an elevator and placed into a feeding container above the optical sorter at a height of 6 m. The optical sorter was placed at a height of 3 m above the ground to allow the gravitational capture in big-bags of the products coming out of the equipment. The following notations were used for the components that came out of the optical sorter: \"accept\" for the component that included the basic product, the useful part from the machine; \"reject\" for the component that included the impurities; \"mechanical losses\" for the material component that was created by the machine as a result of its operation; and \"dust\" for the component resulting from the pneumatic cleaning of the product being processed. Figure 1: The technological flow considered in solving the problem. Two approaches were used simultaneously to analyze the quality of the work provided by the optical sorter:  
1. The analysis was based on the sampling before the material entered the optical sorter for processing and from the machine output; by comparing them, the influence of the equipment on the product could be determined. 2. The analysis was conducted on the passage flow of a precisely known amount of an \"artificial impurified\" raw material. The level of contamination could be determined by weighing and comparing the influence of the machine on the mixture used. The operations performed during the experiments consisted of the following:  
* Filling the feeding basket of the sorting machine directly, with the help of the front loader. * Carrying out the optical sorting operation and obtaining the output components based on the relating performed by the representative of the farm using corn seed from the OLT hybrid, LR caliber, and from the JOKARI CS hybrid, MR caliber. * Weighing the input and output components in/out of the equipment and recording the data. * Sampling, manual sorting by quality elements, and weighing the fractions for the application of the first verification method. * Weighing artificial impurities before forming the mixture and manual sorting by sifting the product of artificial impurity from \"reject\"; collecting and weighing the mass of seeds in order to establish and separate the seeds for the application of the second verification method. Figure 2 describes the seed separation installation for two different feeding methods: Figure 2a depicts the automated loading; Figure 2b shows the feeding process using a front loader; Figure 2c offers an in-depth perspective of the optical separation process. Figure 2: Optical separation of corn seeds: (**a**) automated feeding using a vertical conveyor; (**b**) direct feeding with seeds using a front loader; (**c**) in-depth perspective of the optical separation process. The installation is composed of the following: 1—equipment supporting stand; 2—stiffening beams; 3—feeding stand; 4—vertical conveyor; 5—seed orientation pipe; 6—optical sorter feeding funnel; 7—optical sorter equipment; 8—funnel for big-bag loading; 9—big-bag for seed output; 10—power supply; 11—front loader; 12—big-bag for loading seeds directly using the front loader.