Design and Manufacture of a Portable Grass Chopping Machine Equipped with a Conveyor System to Enhance Livestock Feed Efficiency

Conventional forage processing is often inefficient due to high time and labor demands, alongside size inconsistencies that trigger feed rejection. This study aimed to design, fabricate, and analyze a portable, conveyor-fed grass chopping machine for processing Napier grass using an engineering design approach. The machine is powered by a 5.5 HP gasoline engine (Tesla brand) equipped with four High-Speed Steel (HSS) blades and a 120 cm looped PVC conveyor belt. Performance was evaluated at three initial no-load speeds: 1,537; 2,454; and 3,543 RPM. Results demonstrated optimal performance at 3,543 RPM, where the speed drop under Napier grass load was minimized to 90 RPM (reaching 3,453 RPM). This yielded a peak mechanical efficiency of 97.45% due to the shaft flywheel effect. Peak production capacity reached 576.3 kg/hour (9.605 kg/min) with fuel consumption of ±1.5 L/hour, marking a significant increase over the manual chopping baseline (150 kg/hour). High rotational speed and sharp HSS blades produced uniform Napier grass cuts ranging from 5 to 20 mm (averaging 10–20 mm), optimizing palatability and silage compaction. The machine effectively enhances feed productivity and farm efficiency.