# Stress and Fatigue Analysis of Picking Device Gears for a 2.6 kW Automatic Pepper Transplanter
## 4 Conclusions  
In this study, different materials and dimensions of an automatic pepper transplanter picking device gear mechanism were evaluated to identify those that achieved suitable gear mechanical properties using a non-linear FEA simulation and loads acting on a gear set. A torque measurement test bench was developed to analyze the load condition of the picking device gear under different operations. Based on the FEA simulation, the maximum stress value was observed at the contact point of the mashing gear and pinion. The stress analysis result also indicated that the high- and middle-carbon steel materials were appropriate for the design of this type of picking device gear mechanism. The high-carbon steel material was more expensive than the middle-carbon steel material, therefore it would increase the manufacturing cost. For example, a middle-carbon steel material (for example, SCM 420H carbon steel) with a carbon percentage of 0.25 to 0.60% could be used for the picking mechanism gear set. To evaluate the fatigue life of the gear, the damage was calculated using the load duration distribution method and S-N curve, based on torque data measured in the experiment. According to the fatigue analysis, the damage of the working load on the transmission increased with increasing gear speed, and the SCM 420H carbon steel with a 5 mm face width was suitable to operate the picking device for a 10-year (recommended) service life. The theoretical and experimental results of this study provide useful information for gear set design for an automatic pepper transplanter picking mechanism. In particular, the results can be used for designing optimal pepper transplanter transmissions, thereby improving design reliability and reducing material costs. Conceptualization, S-O.C., and M.N.I. ; methodology, S-O.C., and M.N.I. ; software, M.N.I. ; validation, M.N.I., S-O.C., and D.-H.L. ; formal analysis, M.N.I., M.Z.I., and M.A. ; investigation, S-O.C., and M.S.N.K. ; resources, S-O.C. ; data curation, M.N.I., M.Z.I., M.S.N.K., and M.A. ; writing--original draft preparation, M.N.I. ; writing--review and editing, S-O.C., D.-H.L., and M.C. ; visualization, M.N.I., M.Z.I., M.C., and K.S. ; supervision, S-O.C. ; project administration, S-O.C. ; funding acquisition, S-O.C. All authors have read and agreed to the published version of the manuscript. This work was supported by the Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry, and Fisheries (IPET) through the Advanced Production Technology Development Program, funded by the Ministry of Agriculture, Food, and Rural Affairs (MAFRA) (project no. 317013-03), Korea. Figure 10: Predicted fatigue life hours of the picking device gear mechanism for the 10-year service life: (**a**) crank gear and (**b**) cam gear. * [PERSON] et al. (2015) [PERSON]; [PERSON]; [PERSON]; [PERSON] Experimental and analytical study of gear micropitting initiation and propagation under varying loading conditions. _Wear_**2015**, _328-329_, 8-16. [CrossRef]
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