Design development and techno-economic assessment of a solar-powered three-row chickpea leaf nipping and collecting machine for sustainable farming

Abstract

Agricultural mechanization enhances productivity and reduces manual labour in labour-intensive regions. Chickpea, a major pulse crop in India, is widely cultivated in semi-arid regions of North Karnataka, particularly in Vijayapura district. In 2024, 500,000 hectares of pigeonpea and 1.9 million hectares of chickpea were sown in this region. In chickpea, leaf nipping is a vital agronomic practice that encourages branching and improves yields. However, this practice is done manually, making it highly labour-intensive, time-consuming, and less feasible for small-scale farmers. To address these challenges, the current research focuses on the design, development, and techno-economic evaluation of a solar-powered, three-row leaf-nipping and collecting machine. This machine is equipped with a 150 W solar PV system, six 15 W BLDC motors, and an adjustable cutter-head assembly for efficient operation. A techno-economic analysis was conducted to evaluate cutting force, torque, power consumption, and battery discharge characteristics, as well as the payback period, cost savings, and improvements in farm income. Field trials conducted on a 9-acre farm in Vijayapura, receiving an average annual solar irradiation of approximately 1950 kWh/m², demonstrated 350-400 kg of leaf collection and a 25-30% increase in crop productivity. The machine provides a cost-effective, eco-friendly, and scalable solution for small and medium-scale farmers.