• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.6
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• pp.77-86
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• 2016

Due to aging of the rural and mountain populations the labor force is reduced. However work intensity continues to increase, thus, there is a need to improve the current effectiveness of forest operations. This study compared and analyzed the Operation productivity and efficiency of planting containerized seedlings using a battery-powered planting auger and a mattock. Growth was also investigated by looking into the initial growth increments in the planted seedlings. Tasks were investigated by analyzing the process and operation time needed to plant 1 containerized seedling using a planting auger and a mattock. The time spent on the various elements of the planting process was measured with a stopwatch but observations were done continuously. Result of the study shows that with the use of a lightweight planting auger the average time spent to plant a containerized seedling is 18.61 seconds while with the use of a mattock it took an average of 26.96 seconds which clearly demonstrates that the planting auger is more efficient in terms of working hours. Working intensity was also analyzed with the use of a portable heart rate monitor (Polar V800). The average increase in heart rate and work intensity index were analyzed for one planting cycle. It was observed that when using the lightweight planting auger, there was a 46.51% increase in the average heart rate while a 74.67% increase in heart rate when the mattock was used which shows that there is a significant increase in heart rate when mattock is used. In addition, work intensity index was observed to be 29.95% and 47.83% when the planting auger and mattock were used respectively. With the continuous use, work intensity index is significantly higher with the use of the mattock as compared to that of the lightweight planting auger. There were no significant differences on the growth increment of seedlings planted using the different tools until a year after planting, however differences in growth increment were observed after a year. A difference of 15.1 cm in height and 3.41 mm in diameter was observed which shows that the use of lightweight planting auger is excellent for planting containerized seedlings.

• Journal of Korean Society of Forest Science
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• v.106 no.4
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• pp.465-472
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• 2017

In this study, containerized seedlings of Pinus densiflora (2-0) were planted in Iso-ri, Hwadong-myeon, Sangju-si, Gyeongbuk on April, 2015. It was planted by lightweight planting auger that Kyungpook University has developed and mattock which is the general planting method of containerized seedlings. With the square planting method ($1.8{\times}1.8m$), 225 trees were planted respectively and about 2 years of initial growth, survival rate and seedling quality index (SQI) were analyzed and investigated. According to the analysis result, the average root collar diameter (mm) of planted containerized seedlings that used lightweight planting auger and mattock reached 3.77 and 3.94 in 2015, 18.73 and 15.32 in 2016, and 27.8 and 23.9 in 2017 respectively. In addition, the average height of containerized seedlings rated 33.4 and 33.4 in 2015, 89.8 and 74.7 in 2016 and 120.7 and 97.9 in 2017. It turns out that the height of initial growth of containerized seedlings that are planted by lightweight planting auger were much higher than mattock. The survival rate of the containerized seedlings that used lightweight planting auger was also higher by 10% than that used mattock. Also, H/D rate (healthiness) and T/R rate were almost the same, however, for the SQI, 0.60 was for lightweight planting auger and 0.24 for mattock. It seems like the lightweight planting auger is more advantageous than mattock in initial growth.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.62-62
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• 2017

모터와 스크류를 이용한 경량 식혈기를 처음으로 개발함에 따라 실제 산림의 식재 시험에서 발생될 수 있는 것은 감속기와 스크류의 연결부분의 파괴이다. 이 감속기 축의 파괴는 토양내부의 큰 자갈로 인해 스크류가 낄 경우 식재봉을 좌우로 흔들게 되면 가장 취약한 부분인 스크류와 감속기의 연결부위에 가장 강한 모멘트가 걸리게 된다. 물론 작업자의 부주위가 원인이기도 하지만 감속기(K6G30C. Korea)의 축 지름이 8mm이므로 식재봉을 좌우로 흔들면 굽힘파괴가 일어날 가능성이 높다. 감속기의 축이 파괴가 되지 않게 하는 방법은 재료의 강도가 높은 새로운 감속기를 찾은 일과 기존 감속기의 축을 굽힘응력에 안전하게 대응할 수 있게 설계를 하는 방법이 있다. 본 연구에서는 전자에 대한 조사와 동시에 후자에 대한 설계와 제작을 수행하여 기 제작된 경량식혈기와 비교 분석하였다. 스크류 축의 굽힘응력에 대한 대응 방법으로 감속기 축의 보강방법은 감속기 축에 식재봉으로 부터 굽힘응력이 직접 전달되지 않게 하기 위해 모터 하우징의 하부 위치에 감속기 축을 감싸는 Radial Bearing을 결합하였다. 그리고 스크류의 축은 상단의 지름을 크게 키운 상태로 감속기의 축에 연결하는 방법으로 설계하였다. 이때 식혈봉으로 부터 걸리는 모멘트는 스크류의 상단 지름에 걸리게 되는데 상단부는 모터 하우징의 하단과 단단하게 결합함으로써 감속기 축을 보호하게 되고 또한 감속기 축의 길이에서 Bearing과 스크류 상단부 큰 지름이 각각 반반씩 보호하는 형태로 설계하였다. 이와 같이 감속기의 축을 보강한 경우 종전의 식혈기보다 무게가 무거워지게 된다. 즉, 1차 식혈기 무게는 3.38kgf, 2차 시작기는 3.28kgf, 축 강도가 보강된 3차 시작기는 무게가 3.87kgf로 증가되었다. 따라서 종전보가 약 600g 증가되어 다소 무거운 느낌이 들었다. 여기서 리듐 폴리머 배터리와 가방의 무게 3.23kgf를 부가하면 1차, 2차, 3차 시작기의 무게는 각각 6.61kgf, 6.51kgf, 7.1kgf로 나타났다. 따라서 굽힘응력에 대한 보강의 방안으로 설계된 무게 과다가 현장 시험에서 작업자의 피로도 증가와 작업의 비효율성이 예상되어 포트묘의 현장 식재시에 이에 대한 평가를 수행하여 비교 분석할 예정이다.