Design, Fabrication, and Testing of a Horizontal Weeding Machine

Abstract

This research work focused on the design, fabrication and performance evaluation of a horizontal weeding machine which is powered by a 6 hp petrol engine. The research work was aimed at reducing cost, labour, stress and time wastage involved in the weeding operation on the farm. The machine consists of frame, pulleys, belt, bearings, the petrol engine, depth adjuster, set of weeding blades, frame support, protector, and wheels. The machine was fabricated from locally sourced materials, which makes it cheap and easily affordable and also easy and cheaper to maintain. The machine was tested at the soil moisture content level of 16 % and operation depth of 35 mm. The result revealed that the weeding efficiency increased with an increase in blade rotational speed from 1000 rpm to 2500 rpm. Also, increasing the operator's speed from 0.54 km/hr to 1.26 km/hr increased the weeding efficiency from 90.8% to 97.6% and then decreased to 52.3% with further increased in speed to 1.62 km/hr. The effective machine capacity increased with increasing operator's speed from 0.54 km/hr to 1.26 km/hr and then decreased with further increase in speed to 1.62 km/hr. Also blade type and grass types both have significant effects on the weeding efficiency and effective capacity of the machine, with spear grass and horizontal blade-type having the highest significant effects. The developed machine is efficient, reduces stress, drudgery and increased area of covered per unit time. The total cost of construction of the machine was $137.