Design, Fabrication and Evaluation of a Hand-Operated Semi-Automatic Chopping Machine for Leafy Vegetables and Medicinal Herbs

Abstract

A hand-operated semi-automatic vegetable chopping machine was designed, fabricated and evaluated to introduce an efficient chopping machine to ease the preparation of leafy vegetables and herbal medicines. The main features and components of the chopping machine were integrated cutting and feeding mechanism, operating handle, cylindrical container, piston, collecting drawer and the frame. The machine was designed to operate manually reducing the operational & capital cost and to ease the use in rural areas, where there is no electrical supply. A performance test was done for this machine using four different leafy vegetables and medicinal herbs [Mukunuwenna (Alternanthera sessilis), Kankun (Ipomoea aquatica), Gotu kola (Centella asiatica) and Kathuru murunga (Sesbania grandiflora)] in comparison with manual chopping using a general kitchen knife. Five unskilled males and females were involved in a performance test with three replicates. The three-factor factorial experimental design was used in the evaluation. The actual capacity and the efficiency of the chopping machine were 1.81 kg h-1 and 74%, respectively compared to 1.02 kg h-1 and 76% of the manual kitchen knife. The average width of a particle cut by machine and kitchen knife were 1.87 mm and 3.38 mm, respectively. According to the user-feedback, this machine is a safe, affordable and convenient device for processing vegetables and herbal medicines.