Plant Moisture Sensor

Work-in-Progress

 

Plant Name: Stew

Objective

Determine the moisture levels in my often-dying plants to provide more insight into how often I should be watering.

I enjoy making plots as well.

 

Software

-Python

-bash

-Arduino IDE

Hardware

-Arduino

-Soil Sensor

 
 

Calibration

I want to get an idea of my sensor’s capabilities so I start by calibrating the sensor and logging the data in a controlled environment.

I accomplish this by submerging my sensor in a mug of water.

testLoop.gif

Calibration of Sensor

 

Arduino Code:

void setup(){
     Serial.begin(115200);
}
void loop() {
     int val;
     val = analogRead(0); //connect sensor to Analog 0
     Serial.println(val); //print the value to Serial
     delay(10);
}

 
dacq.jpg

I was lucky and able to borrow a data acquisition system for a few days.

 
 
calibrate_Dacq.png

Serial Output <> Voltage Readings

Knowing my Arduino has 10-bit resolution (2^10 or 1,024 ADC readings), I can get my estimated serial output as a function of voltage.

I repeated the calibration (dunking and retrieving the sensor in just a mug of water) and plotted the voltage measurements.