# Performance Testing and Evaluation of Drum-Type Stem-Separation Device for Pepper Harvester
###### Abstract  
The chili pepper harvester has shown potential problems of low pepper stem separation and a high pepper damage rate. The low pepper stem separation has required additional labor, which consists of separating the pepper and stem after pepper harvesting. To improve the stem separation and sorting function of pepper harvesters, three-shaft and four-shaft drum-type stem-separation devices were manufactured, and performance tests were conducted to assess these devices. In an attempt to reduce the damage rate, a brush was used as the teeth in the drum-type stem-separation device. In the factor test, the rotational speeds of shaft 1(A), shaft 2(B), shaft 3(C), and the conveyor for the three-shaft drum were 0.9, 2.7, 1.3, and 0.5 m/s, respectively. The rotational speed of the four-shaft drum was the same as that of the three-shaft drum except for shaft 4(D), and the rotational speed of this additional D was set to 1.3 m/s, which was the same as that of C. In the non-moving status during the non-picking operation of the pepper harvester, the average stem-separation efficiency (SSE) of the four-shaft drum increased by 1.2%, the average pepper with twig rate (PTR) decreased by 5.9%, and the average damage rate (DR) increased by 3.7% compared to the three-shaft drum. In the moving status during the picking operation of the pepper harvester, the SSE of the four-shaft drum increased by 3.6%, the PTR decreased by 9.1%, and the DR increased by 3.8% compared to the three-shaft drum, so an improvement in the pepper stem-separation capacity was observed. chili pepper harvester; drum type separating system; prototype; stem-separation of foreign materials; performance; evaluation; field test +
Footnote †: journal: Medical  
Research on chili pepper varieties for use in mechanical harvesting has been conducted [16]. Recently, to evaluate the suitability for harvest mechanization, previous research was conducted on the nutritional and physiological components of various varieties [17; 18; 19; 20; 21] as well as plant spacing, productivity, and quality [22; 23; 24] according to cultivation methods. The self-propelled chili pepper harvester consists of the picking and transfer parts that remove peppers from plants, a separation sorting part that removes small branches and leaves, and a collecting part that contains the peppers [25]. Previous studies were conducted on the separation sorting part using a star wheel and a card cleaner [26; 27; 28; 29] as well as using an air blower [26; 30] to remove small branches. When bigger particles, such as stemmed chili peppers, flow in from the picking part, the development of additional separating and sorting devices are required. [PERSON] et al. [31] obtained a PTR of 24.2-37.8% in a chili harvester comparison test, and suggested the need for a stem-separation and sorting device to reduce the input of additional manpower for sorting work after the chili harvest. Studies on stem separation used a rotating roller method and a drum-type threshing method. A study on a rotating roller method conducted by [PERSON] et al. [32] reported that, as a result of a pair of feeding rollers rotating in opposite directions putting a whole paprika plant, including roots, into the two pairs of picking elements, the number of stem-attached peppers was reduced by 50% compared to that of work without a stem-separation system. [PERSON] et al. [33] reduced the amount of stem-attached cherry peppers by more than 90% by placing stem-attached cherry peppers between roller beds of different sizes. [PERSON] et al. [34] developed a system for separating stems using three cylindrical squeeze rollers rotating clockwise at the top and eight downstream rollers rotating counterclockwise at the bottom. [PERSON] et al. [35] designed and simulated an automated system that detects the color of bell peppers and separates the pepper from the stem by a roller-driven belt. A study by [PERSON] et al.