Wi-Fi Enabled Soil Moisture Sensor

Overview

• Circuit to Measure Capacitance• Soil Moisture Sensor• Electric Imp (Wi-Fi)

Measuring Capacitance

)

h𝑊 𝑒𝑟𝑒𝜏=𝑅𝐶𝑅𝑒𝑎𝑟𝑟𝑎𝑛𝑔𝑖𝑛𝑔𝑇𝑒𝑟𝑚𝑠…… ..

𝐶=−𝑡

𝑅∗ ln (1−𝑉 (𝑡 )𝑉 0

)

𝐸𝑞𝑢𝑎𝑡𝑖𝑜𝑛𝐹𝑜𝑟 𝑎 h𝐶 𝑎𝑟𝑔𝑖𝑛𝑔𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑜𝑟 :

Measuring Capacitance

Measuring Capacitance

Measuring Capacitance

Measuring Capacitance

Measuring Capacitance

Measuring Capacitance

View of The Circuit

Circuit Output

Soil Moisture Sensor

Circuit Output With Sensor In Soil

Circuit Output with Sensor in Air

Testing

Using Capacitance to Estimate Dielectric Value of the Soil

C 𝜀0=Vacuum Permittivity

Testing Results

5.00E+00 1.00E+01 1.50E+01 2.00E+01 2.50E+01 3.00E+010

2

4

6

8

10

12

14

16

18

f(x) = 0.691042616968669 x − 3.21588628446756R² = 0.68086321570672

Soil Moisture Probe Dielectric (Capacitance / Vacuum Permittivity)(F/m)

Deca

gon

Diel

ectr

ic (F

/m)

Electric Imp

Sending Emails of Dielectric Values

Sending Emails of Dielectric Values

Future Plans

• Enclosure• Further Testing to Improve Capacitance

Measuring Circuit• Better Calibration