Autonomous Arduino Fertilizer Spreader

Overview

Role - Mechanical Designer | Controls Programmer | Manufacturing

Tools - AutoCAD, Arduino Uno, C++, 3D Printing

Skills - CAD Design, Embedded programming, Rapid prototyping, Mechanical design, Electronics integration, Systems integration, testing & validation

Design Process

The project began with the design and fabrication of a 3D-printed trailer to house the fertilizer dispensing system. Initial testing revealed that the original design was too large and heavy, limiting maneuverability. The trailer and wheel geometry were iteratively redesigned to create a lighter, more compact platform with improved mobility.

To simplify the electrical system, the dispensing mechanism was designed around a single servo motor, maximizing functionality while minimizing wiring complexity and component count. The rotating dispensing disc was tuned to accurately direct fertilizer through one of two outlets under servo control.

Once all subsystems were operating reliably, the design was refined with a focus on reducing weight, improving packaging, and increasing serviceability. Design for Manufacturing (DFM) and Design for Assembly (DFA) principles guided many of these decisions to simplify fabrication and reduce maintenance.

The Arduino control program was developed and tuned for the competition course, including adjustments to sensor thresholds, motor control, timing delays, and line-following performance across different surface materials.

Results

The completed system successfully performed all required competition tasks, including line following, obstacle avoidance, controlled fertilizer dispensing, and infrared signaling. Out of more than 80 competing teams, the robot achieved the fastest overall course completion while successfully completing every task. The project also received 2nd place for the People's Choice Award for its overall design and presentation.