Performance Evaluation of a Height Adjustable Mini Combine Harvester

Abstract

Mini combine harvesters have been very popular among paddy farmers. The compact size of the machine, in addition to the axial flow threshing mechanism and the effect of low ground pressure on paddy soil, makes it a potential alternative for efficient paddy harvesting of a height-adjustable mini combine harvester used for harvesting paddy fields. This type of harvester was tested in typical paddy field conditions planted with MR297 variety at MARDI Seberang Perai. The performance tests included measuring theoretical and effective field capacity, field efficiency, soil bearing capacity before and after machine disturbance and machine slippage. The fuel consumption was also recorded. The combined harvesting losses were also measured during the experiment. Results showed that in wet and muddy conditions, the mini combine harvester obtained a theoretical field capacity (TFC) of 1.28 ha/hr, effective field capacity (EFC) of 0.94 ha/hr and a field efficiency (FE) of 73.4%. The average fuel consumption of the mini combine harvester was 25 L /ha. The wheel slippage in wet paddy fields was 2.18% and on farm roads was 1.55%. The mini combine harvester also contributed to producing less ground effects, combined with the use of low ground contact pressure tracks, that caused minimal soil disturbance that would affect the soil hardpan layer. This mini combine harvester produced an average harvesting loss of 2.3% with an average harvesting impurity of 10.65%.  The mini combine harvester had enough power to move in typical paddy field conditions, with no soft soil problems. The mini combine harvester was able to turn 360 degrees within a small area, which made it suitable for harvesting in paddy fields. Thus,  this mini combine harvester has the potential to be used for paddy harvesting with the ability to not only produce minimal harvesting loss, but also produce less ground contact pressure which can help to manage the soil hardpan layer from being easily damaged.