Effects of Saw Blade Geometry on Oil Palm Frond Cutting

Harvesting oil palm is heavily reliant on manual effort due to the high cutting force required, especially with traditional sickles featuring narrow wedge angles.Mechanised alternatives, such as reciprocating saws, offer potential to reduce manual efforts.This study investigates the influence of frond cutting angles (0, 15, 30, 45, 60), feed rates (5, 10, 15 mm/s), and blade types (Jigsaw blade and heavy-duty pruning blade) on cutting forces using a cordless electric reciprocal saw.Specific Cutting Force (SCF), defined as the cutting force per volume of frond removed per stroke, was found to be higher for the jigsaw blade compared to the heavy-duty blade.At a 0 relative frond cutting angle and 15 mm/s feed rate, the SCF for the jigsaw blade increased from 0.35 N/mm to 1.64 N/mm, while the heavy-duty blade showed a smaller increase from 0.14 N/mm to 0.69 N/mm.The jigsaw blade's performance declines at higher frond angles and feed rates, requiring up to 280% more force than the heavy-duty blade under those conditions.Cutting efficiency, notably at 30 frond cutting angle, the heavy-duty blade was over 250% more efficient than jigsaw blade, highlighting its advantage in high demand cutting conditions.These findings highlight the importance of blade design and cutting conditions in optimizing harvesting efficiency, with mechanized tools like the reciprocal electric saw reducing worker strain and improving productivity.The findings support the use of mechanised tools to reduce physical strain and enhance efficiency and can support the design of advanced robotic or drone-based automated harvesting systems for the oil palm industry.