Design, Development and Analytical Assessment of a Low-Cost Multipurpose Agricultural Fixture for Simultaneous Weed Control and Pesticide Application in Smallholder Farming

Abstract

Smallholder farmers in developing countries face persistent challenges in weed management and pesticide application because of labour shortages, increasing operational costs, and occupational exposure to agrochemicals. This study presents the design and analytical assessment of a low-cost multipurpose agricultural fixture mounted on a conventional two-wheeler platform to combine inter-row weed cutting and pesticide spraying in a single pass. The prototype incorporates a mild-steel structural frame, three adjustable weed-cutting blades, a 60-L polyethylene tank, a 12-V battery-operated pump, delivery lines, and adjustable hollow-cone nozzles. A SolidWorks model was developed considering crop-row spacing, crop height, vehicle geometry, and operator accessibility. Preliminary draft force and power requirements were estimated using the modified ASABE Universal Draft Equation; the estimated draft force was 3177.59 N and the corresponding power requirement was 1.32–2.65 kW over an operating-speed range of 1.5–3 km h−1. Importantly, these values are analytical design estimates and were not experimentally validated using a drawbar dynamometer, load cell, torque measurement, or wheel-slip instrumentation in the present study. Prototype operation was assessed qualitatively for integrated blade engagement and spraying functionality, but quantitative measurements of weeding efficiency, spray deposition, crop damage, traction, structural response, and energy consumption were not undertaken. Accordingly, the present work establishes a preliminary design and feasibility framework rather than a fully field-validated performance claim.