Design & Construction of a four row tractor drawn Irish potato harvester

Abstract

Irish potato (Solanum tuberosum) is one of the most important a root vegetable grown in Uganda. It is a rich source of carbohydrate, used all over the country. Harvesting is one of the most important operations in Irish potato cultivation. However, it is one other most difficult task which accounts for the considerable share of costs involved in an agricultural production. The commonly used methods in Irish potato harvesting include; use of hand hoe, curved sticks, ox-plough potato lifter,garden forks and others

Harvesting of Irish potato is a major challenge in Uganda due to lack of appropriate technology and funds inspite of its high economic potential in the country. Small and medium scale Irish potato growers mostly use long and tedious methods which involves the use of human muscles. These methods are labor demanding, time consuming, compromises the quality of Irish potato. The proposed study is therefore intended to design a tractor drawn Irish potato harvester which simultaneously separates Irish potato, soil and plant residue in a single process to present the above challenges. Different components of the machine were designed which include; the hopper, separator, main shaft and idle shafts, digger blade, main frame, driving mechanism and analysing forces acting on the components to prevent failure. From the designs, separator operates at a speed of 90 rpm with a total maximum transmitted power requirement of 50.04HP, though 65HP can run the system with the same results After fabrication, the performance and economic analysis of the machine were performed in terms of field efficiency resulted into 76%. Machines total cost; Ugx.1.8M, monthly income; Ugx. 1.56M and pay back-period of 1.2years Owing to the performance and economic analysis of the machine, it achieves all its design purposes hence it is recommended for commercialization and adoption by the target groups.