Design and development of IoT based solar power agriculture robot

Agriculture in developing economies such as Pakistan remains heavily dependent on manual labor and single-purpose, grid or fuel-powered machinery that is often unaffordable for smallholder farmers. This paper presents the design, fabrication, and experimental evaluation of a multifunctional, solar-powered, Internet of Things (IoT)-enabled agricultural robot capable of performing soil cultivation, seed placement, irrigation, and crop cutting within a single integrated platform. The system architecture is built around an ESP32 microcontroller that interfaces with a DHT11 temperature/humidity sensor, an HC-SR04 ultrasonic obstacle sensor, an ESP32-CAM module for visual field monitoring, an L298N dual H-bridge motor driver, and relay-controlled actuators, with energy supplied by a 20 W photovoltaic panel, a 12 V/7.2 Ah battery, and a battery management system (BMS). Mechanical subsystems comprising a tooth-type cultivator, a soil-leveling roller, a servo-actuated seed dispenser, a DC pump-based irrigation unit, and a blade-type cutter were designed in CAD, fabricated, and integrated onto a four-wheel-drive chassis. Engineering calculations were used to size the power budget, battery backup, drive-motor torque, structural factor of safety, seeding rate, and irrigation flow. Field trials show a typical operating power demand of 24.4 W against an average usable solar output of 11–12 W, a battery backup of approximately 3.5 h, The experimental results demonstrated satisfactory performance of the proposed agricultural robot, achieving an average seed-placement accuracy of 74.45% over 11 experimental trials. The developed system also successfully performed soil digging, irrigation, crop cutting, obstacle detection, and real-time IoT-based remote monitoring, demonstrating its suitability for sustainable precision agriculture.