Smart Auto-Watering Pot

Status: Prototype Goal: Simple, open-source auto-watering system that anyone can build and experiment with.

The Mechaxil Smart Auto-Watering Pot is a compact system for keeping a single plant automatically watered.

It uses a Capacitive Soil Moisture Sensor

Measures soil humidity via capacitance change instead of resistance. Corrosion-resistant and provides analog voltage proportional to moisture.

connected to a Development board of choice

A printed circuit board (PCB) that includes a microcontroller or microprocessor, along with necessary components and interfaces for prototyping and development.

running MicroPython

A compact version of Python for microcontrollers like the ESP32 and Raspberry Pi Pico. It lets you script directly on embedded hardware.

. When the soil gets dry, the controller drives a MOSFET Module

Small logic-level power switch board that lets 3.3V logic control high-current DC loads like pumps or valves.

with a gentle PWM

Pulse Width Modulation - controls average power by switching rapidly. The duty cycle determines the effective output.

soft-start, opening a small DC Valve

A direct-current operated valve, typically a small solenoid valve used to open or close water flow.

or pump and letting water flow from a 3D-printed tank into the pot.

Buy The Kit Buy The Components

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Key features

• Development board of choice
  A printed circuit board (PCB) that includes a microcontroller or microprocessor, along with necessary components and interfaces for prototyping and development.
  + MicroPython
  A compact version of Python for microcontrollers like the ESP32 and Raspberry Pi Pico. It lets you script directly on embedded hardware.
  firmware
• Capacitive Soil Moisture Sensor
  Measures soil humidity via capacitance change instead of resistance. Corrosion-resistant and provides analog voltage proportional to moisture.
  
• PWM
  Pulse Width Modulation - controls average power by switching rapidly. The duty cycle determines the effective output.
  soft-start valve control to reduce inrush current and brown-outs
• RGB LED
  A light-emitting diode that can produce a wide range of colors by combining red, green, and blue light.
  or a regular LED
  A light-emitting diode used frequently as a status indicator in electronic devices.
  feedback
• 3D-printable tank and electronics enclosure

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Mechanical design

All parts are designed to be printable on a typical FDM 3D Printing

Fused Deposition Modeling builds objects layer by layer by extruding melted filament through a heated nozzle.

with a 0.4 mm nozzle.

Recommended materials: PETG

A durable and easy-to-print 3D printing filament known for strength, flexibility, and resistance to impact and moisture.

or ASA

A strong and weather-resistant 3D printing filament, ideal for outdoor applications due to its UV and impact resistance.

(for better water and heat resistance than PLA

A biodegradable and easy-to-print 3D printing filament made from renewable resources such as corn starch or sugarcane.

, altough it works just as well).

Part	Description	Notes
Tank	200-500 ml reservoir	Watertight print, 2-3 mm walls, ≥4 perimeters, optional epoxy sealing inside
Electronics box	Small enclosure for the controller + MOSFET Metal-Oxide-Semiconductor Field-Effect Transistor - an electronic power switch. Logic-level MOSFETs can be driven directly from GPIO pins.	Cable holes high on the wall, lid screwed or clipped in place

STL and CAD files will be published together with this documentation once the v0.1 hardware is fully validated.

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Project goals

1. Serve as the first Mechaxil open kit: small, fully documented, reproducible.
2. Teach fundamentals of analog sensing, PWM
   Pulse Width Modulation - controls average power by switching rapidly. The duty cycle determines the effective output.
   power control and safe power distribution.