Precision Fertiliser Spreader Controller Variant 26 Kit with ESP32 + LED
Precision Fertiliser Spreader Controller Kit: GPS-Guided Variable Rate Application with ESP32
Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.
For agri-engineers and precision farming researchers, this kit delivers a complete hardware stack to build a fertiliser spreader controller that varies output based on GPS location and soil electrical conductivity. By loading a prescription map onto a microSD card, the ESP32 correlates real-time GPS position and in-field EC readings to modulate a relay via PWM — exactly what modern commercial VRT systems do, in a buildable, open-source form.
What You'll Build
You’ll assemble a weatherproof field unit that sits on a tractor or implement, reads GPS coordinates and soil EC in real time, matches them against a pre-loaded prescription map, and drives a relay that controls the spreader’s metering mechanism with PWM-adjusted duty cycle. The OLED displays current zone, target rate, and actual output, while the RTC and microSD log every application pass for later analysis.
What You'll Learn
- Fusing NMEA GPS sentences with soil EC data to implement true variable rate logic
- Parsing geo-referenced prescription maps from SD card and matching zones via nearest-neighbour search
- Generating stable PWM signals with the ESP32 LEDC peripheral for smooth relay control
- Designing a rugged power supply with buck converter and filtering to survive tractor electrical noise
Kit Contents
| Component | Quantity |
|---|---|
| ESP32 Dev Board | 1 |
| NEO-6M GPS | 1 |
| TDS EC Meter | 1 |
| DS3231 RTC | 1 |
| MicroSD Module | 1 |
| IRF540N MOSFET | 1 |
| LM2596 Buck Converter | 1 |
| 0.96in OLED | 1 |
| 100nF Caps | 10 |
| 4.7kΩ Resistors | 5 |
| PCB Prototype Board | 2 |
| Waterproof Enclosure | 1 |
| 12V PSU | 1 |
| Soldering Iron | 1 |
| Solder Wire | 1 |
Why Buy This Kit Instead of Sourcing Parts Separately
| Factor | Sourcing Separately | Compoden Kit |
|---|---|---|
| Compatibility checks | You verify every part | Pre-tested as a system |
| Build support | Forums and scattered tutorials | AI companion trained on this exact project |
| Time to first working build | Days of debugging | Hours, with step-by-step guidance |
| Shipping coordination | Multiple sellers, multiple delays | One shipment from Bengaluru in 3-5 days |
Who This Kit Is For
B.Tech and M.Tech students in agricultural engineering, electronics, or IoT streams tackling precision farming projects; Smart India Hackathon teams building agritech solutions with hardware; and R&D labs prototyping variable rate technology for Indian field conditions. If you already understand embedded C/C++ and have wired an ESP32 before, this kit takes you straight to field-ready integration.
Built and Backed by Compoden
Every Compoden kit ships with an AI build companion trained on this exact project — accessible via a QR code on the box, with WhatsApp and email backup. We've spent 10 years building projects for makers, schools, and institutions across India. If a part fails because of a manufacturing defect, replace it free within 7 days.
What if I get stuck during the build?
Open the AI companion on your phone — scan the QR code from the kit box. If it's after midnight and you'd rather text a person, WhatsApp support is available for this advanced kit.
Can I test the system without an actual tractor and spreader?
Yes. The kit includes a 12V PSU and relay output simulates the spreader motor. You can bench-test the entire GPS-EC-PWM logic on a breadboard before field installation.
How do I prepare the prescription map for the SD card?
The AI companion includes a Python script to convert shapefiles or GeoJSON into a CSV grid the ESP32 can parse. You’ll load the map with zone IDs and target rates, and the code matches GPS to the nearest grid cell.
What about electrical noise from the tractor’s alternator?
The LM2596 buck converter and the 100 nF capacitors on the power rail are specifically chosen to suppress voltage spikes. We also recommend a ferrite bead on the 12V input — the AI guide walks you through that optional addition.
GPS and soil EC map guide variable rate spreader relay opening via PWM to match pre-loaded prescription map.
What's in this kit
Choose your assembly option:
- Soldering Kit — 25W soldering iron, 60/40 solder wire, flux, and small perfboard for permanent assembly.
- Breadboard Combo — 800-point full-size breadboard with 65-piece jumper wire pack for solderless prototyping.
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Shipping Information
- Prepaid Orders: ₹75 for orders up to ₹999, FREE shipping above ₹999
- COD Orders: ₹125 shipping + ₹50 COD fee = ₹175 total
- Delivery Timeline: Dispatch in 1-2 days, delivery in 2-7 days depending on location
Returns & Warranty
- 7-Day Return: Manufacturing defects only (approval required)
- Warranty: 7 days from delivery
- Non-Returnable: Batteries, consumables, cut wires, clearance items