DEVELOPMENT OF A MECHANICAL HARVESTER FOR AMARANTHUS

Abstract

A lot of drudgery is involved in the manual harvesting of leafy vegetables. Therefore, with small and medium scale farmers in mind, a low cost leafy vegetables harvester was developed. The major components of the machine are the frame which support the other components, chopper knives which cut the vegetable stems about 6 ern from the soil surface, set of spur gears which drives the propelling land wheels .. The machine is rugged and sturdy, and it was designed to harvest leafy vegetables such as Amaranthus Spp, water leaf, soko and Solanium nigrum (odu). The experimental machine was designed to be coupled to the tractor to hasten harvesting. However the experimental machine prototype was manually pushed to harvest the vegetable during testing, to permit monitoring of the machine performance at close range. The operating speed of the machine during harvesting was 3 k.m/h. For the purpose of evaluating the performance of the harvester, a field was prepared where atnaranthus was planted at different weeks interval. The following parameters were varied during harvesting, moisture content of the soil and age/maturity of vegetables. Prior to harvesting, two growth parameters of the amaranthus plant, that is stem diameter and height of crop were determined and were used for design calculation. The result of the tests performed on machine show that it is appropriate for small farm holders. Furthermore, it shows that the Field Efficiency of the machine was influenced by moisture content of the soil and the age of crop at harvest. The machine's maximum Field Capacity was 0.8 ha/h with a Field Efficiency of 82 %. The Quality Performance Efficiency was 60% at 22% Moisture content (wb) of the experimental soil. Harvesting was best at five weeks after planting. The cost of the machine was estimated at about N16,123.