Adoptive design and construction of a of a manual paddy rice transplanter

Abstract

Rice is a crop of growing importance in Uganda with about 75,000 Ha under rice cultivation. In Uganda, rice production has increased rapidly in the past 10 years while the yield has been stagnant. This can partly be attributed to hand methods of seedling transplanting that result in low seedling placement, spacing inefficiencies and drudgery for the farmer which limits the size of field that can be planted. The farmers cannot however turn to imported transplanters due to high import cost prices. To that effect therefore, a manual lowland rice transplanter was designed, fabricated and tested. The working mechanism of the rice transplanter is that seedlings are kept on the tray and allowed to flow down under gravity while 2 planting arms attached to a shaft pick up the seedlings off the seed tray and place them in the ground at the desired spacing, depth and angle of place. The motion of the shaft is given by the ground wheel using chain and sprocket arrangement. The seedlings are planted into the land by a simple four bar mechanism. The planter shall reduce the time taken to transplant seedlings compared to hand transplanting thus allowing more time for harvest. It will as well improve inter-row and intra-row spacing of rice plants to allow for more room to grow, allow plants to get more sunshine and air and produce more tillers unlike when planted randomly. According to the tests done, the transplanter places seedlings at 30cm by 25cm planting distances at a rate of 4 seedlings per second, hence a planting capacity of 0.75 acres per hour. The transplanter was fabricated at Tree shed Engineering Limited. This report also includes a clear methodology indicating the steps taken to design the transplanter and finally the test protocol for performance and efficiency. In conclusion the designed transplanter will be able to reduce drudgery, improve timeliness and improve row spacing of rice plants.