## 1 Introduction  
Peppers account for 22% of commitment vegetables produced in Korea, and they are used to produce the main condiment favored by Korean cuisine due to their unique spicy flavor. In Korea, pepper cultivation area and production weight are reported to have decreased by more than 40% and 30%, respectively, from 53,097 ha and 352,977 tons in 2006 to 28,337 ha and 241,946 tons in 2017 due to a decrease in the agricultural population and the low mechanization rate compared to other field-based crops [1]. Even though the mechanization rates of tillage and soil preparation, mulching, and pest control are 97.7%, 58.5%, and 90.9%, respectively, pepper harvesting has not been mechanized at all due to the growth characteristics of peppers that mean they need to be continuously harvested four to six times (or more) over the course of a season [2, 3]. The National Institute of Horticultural and Herbal Science (Jeonju, Jeollabuk-do, Korea) has developed the Jeokyoung, a chili species suited to mechanical harvesting, so a pepper harvesting machine suitable for this species needs to be developed. [PERSON] et al. [4] analyzed the mechanical and physical characteristics of Korean pepper species to find a species suitable for use with a pepper harvesting machine. In their analysis, the Poisson's ratio,modulus of elasticity, shear modulus, density, recovery factor, and the friction coefficient of the \"AR Legend\" species were investigated; the Poisson's ratio, modulus of elasticity, and the shear modulus were found to be 0.295, 3.295 \(\times\) 107 Pa, and 4.624 \(\times\) 106 Pa, respectively. [PERSON] and [PERSON] [5] proposed and developed a helical type picking design for mechanical pepper harvesting; using this design the yield of pepper was found to increase as the rotation speed of the helical shaft increased. [PERSON] [6] produced picking designs in the form of three-row helical, four-row helical, bar, and semi-circular tooth designs that were evaluated in various tests. The bar type was found to be the picking tooth type most suitable for pepper harvest showing a successfully harvested rate of 77.3% and a pepper left on plant rate of 3%. [PERSON] and [PERSON] [7] conducted a picking performance test for five types of picking design (disk, chain, Creager, Hernandez, and helix) to find the best type. Among these five types, the helix type was found to be the best type for picking, showing a harvest efficiency of 88.3% and a mechanical damage rate of 11.2%. Studies were conducted recently in Korea to develop a self-propelled pepper harvester by improving the existing picking and selecting designs [8; 9; 10; 11; 12; 13]. Field performance tests were conducted for picking with different helix types to determine an ideal design for picking; in these tests, the maximum harvest efficiency was found to be 76%, and the lowest ground fall loss rate and the pepper left on plant rate were found to be 15% and 7%, respectively, for the triple helix design with a shaft speed of 300 rpm, driving speed of 0.3 m/s, and a picking part inclination angle of 40\({}^{\circ}\)[12; 13]. [PERSON] et al. [9] attempted to improve the harvest efficiency by additionally designing and producing a second picking design using a drum. [PERSON] et al. [10] designed and produced a sorting factor test device of a card cleaner type. They conducted a performance test looking at picking out peppers from foreign substances (stone, pepper twig, etc.) using their design. The conditions that led to the fewest foreign substances being picked were an inclination angle of 15\({}^{\circ}\) and rotation speed of 50 rpm. [PERSON] et al. [11] determined the ideal conditions for a card cleaner using a computer simulation with the discrete element method (EDEM). They compared the results with the factor performance test conducted by [PERSON] et al. [10]. The self-propelled pepper harvester developed using the chassis base of a combine [9; 10; 12; 13] is suitable for use in large pepper farms not smaller than 1 ha.