DEVELOPMENT AND PERFORMANCE EVALUATION OF LEAFY VEGETABLE HARVESTER

Abstract

A vegetable harvester for leafy vegetables was developed to enhance mechanized production of herbaceous vegetables. The major components of the harvester include the cutting unit. the frame, the reel. the transmission unit and the storage bin The components were designed using basic engineering principles. as well as Automated Computer Aided Design Software. AutoC AD :2007 version. The harvester was powered from the tractor Power-Take-Off The height of cut is adjusted by the tractor hydraulic system. The performance of the harvester was evaluated in harvesting amaranthus at various knife and forward speeds of the machine as well as different ages of vegetables and heights of cut. This was achieved by dividing the experimental field into sections with each section planted with vegetable to meet the specific operational/field parameters. Data were obtained from each treatment and all were statistically analysed. Result of the tests showed that the field capacity of the machine' increases linearly with increase in knife speed and forward speed. 447 rprn knife speed gave a field capacity of 0.18ha/h at a forward speed of 5.04 krn/h. The harvesting efficiency of the machine at this optimal performance was 68%. At a reduced forward speed of 3.27.7kmh. the effective field capacity of the harvester was 0.20 ha/hr with an efficiency of 9:2%. The performance of the harvester was satisfactory at this speed and it suitable met the design objectives. Attempt to increase the forward speeds of the machine at various knife speeds resulted in the blockage of the cutting unit which increased the down time and subsequently lowered the harvesting efficiency of the machine. The harvesting efficiency of the machine was also reduced when the average height of the vegetable was 69.60 Cm. The reason for this is that the frame of the machine pushed them away , from the reach or the cutting unit. With exception of the conveyor which did not function properly during testing, the harvester performed satisfactorily, Further research work is recommended to improve the workings 01" the com e: or and make the harvester front-mounted as against the current rear-mounted or, self-propelled to enhance the performance of the harvester.