Online Rapid Detection Method of Fertilizer Solution Information Based on Characteristic Frequency Response Features

Area of Science:

• Agricultural Engineering
• Sensor Technology
• Analytical Chemistry

Background:

• Intelligent precision variable fertilization requires real-time monitoring of fertilizer solutions.
• Existing methods may lack the speed and accuracy needed for dynamic agricultural systems.

Purpose of the Study:

• To develop and validate an online rapid detection method for fertilizer type and concentration.
• To design a cylindrical capacitance sensor for this purpose.
• To improve the intelligence of water and fertilizer machines.

Main Methods:

• A cylindrical capacitance sensor was designed utilizing the dielectric properties of fertilizer solutions.
• A characteristic frequency response mode was employed for detection.
• Sine wave excitation signals (1 kHz to 10 MHz) were used to obtain sensor response data.
• A 'first type, then concentration' detection strategy was implemented.

Main Results:

• The sensor demonstrated high stability with a maximum relative error of 0.72%.
• Concentration detection achieved a maximum error of 7.26%.
• The method successfully differentiated between potassium chloride, calcium superphosphate, and urea solutions across various concentrations.

Conclusions:

• The developed sensor and method enable rapid, accurate online detection of fertilizer type and concentration.
• This technology can provide real-time feedback to intelligent water and fertilizer machines.
• The findings contribute to advancing precision agriculture and optimizing fertilization processes.