Granted Patent B2

US 12,553,847 · App. 18/263,374 · Granted Feb 17, 2026

Inventors: Yongkun Sui (Danbury, CT); Madhur Bharath Atreya (Louisville, CO); Gregory Lewis Whiting (Boulder, CO); Jenna Nielson (Longmont, CO)

Assignee: The Regents of the University of Colorado, a body corporate

G01N27/223G01N33/246

Abstract

Claims (44)

1 . A capacitive soil moisture sensor for detecting moisture levels in soil, comprising:

a biodegradable substrate;

a capacitive circuit, wherein:

the capacitive circuit is positioned on the biodegradable substrate, and

the capacitive circuit does not comprise a water-soluble conductor;

an antenna circuit, wherein:

the antenna circuit is positioned on the biodegradable substrate in communication with the capacitive circuit, and

a circuit component located between an output of the capacitive circuit and an output of the antenna circuit comprises a degradable conductor that is configured to degrade when exposed to a soil environment; and

a hydrophobic, biodegradable encapsulating material encasing at least the capacitive circuit and the antenna circuit.

2 . The capacitive soil moisture sensor of claim 1 , wherein the biodegradable substrate comprises an organic material.

3 . The capacitive soil moisture sensor of claim 2 , wherein the biodegradable substrate comprises balsa wood.

4 . The capacitive soil moisture sensor of claim 1 , wherein the water-soluble conductor comprises zinc.

5 . The capacitive soil moisture sensor of claim 1 , wherein the water-soluble conductor comprises zinc.

6 . The capacitive soil moisture sensor of claim 1 , wherein the capacitive circuit comprises a water-soluble binder.

7 . The capacitive soil moisture sensor of claim 1 , wherein the hydrophobic, biodegradable encapsulating material comprises beeswax.

8 . The capacitive soil moisture sensor of claim 7 , wherein the hydrophobic, biodegradable encapsulating material comprises soy wax.

9 . The capacitive soil moisture sensor of claim 7 , wherein the hydrophobic, biodegradable encapsulating material encases at least the capacitive circuit with a thickness that is determined based at least upon a desired sensitivity of the capacitive soil moisture sensor and a desired life of the capacitive soil moisture sensor.

10 . A method for gathering data from a capacitive soil moisture sensor, comprising:

receiving capacitance data from the capacitive soil moisture sensor, the capacitive soil moisture sensor in physical contact with soil, the capacitive soil moisture sensor comprising:

a biodegradable substrate;

a capacitive circuit, wherein:

the capacitive circuit positioned on the biodegradable substrate, and

the capacitive circuit does not comprise a water-soluble conductor;

an antenna circuit, wherein:

the antenna circuit is positioned on the biodegradable substrate in communication with the capacitive circuit, and

a circuit component located between an output of the capacitive circuit and an output of the antenna circuit comprises a degradable conductor that is configured to degrade when exposed to a soil environment; and

a hydrophobic, biodegradable encapsulating material encasing at least the antenna circuit.

11 . The method of claim 10 , further comprising:

prior to receiving the capacitance data from the capacitive soil moisture sensor, inductively powering the capacitive soil moisture sensor.

12 . The method of claim 10 , further comprising:

recording an identification value associated with the capacitive soil moisture sensor.

13 . The method of claim 10 , further comprising:

recording a location value associated with the capacitive soil moisture sensor.

14 . A method for constructing a capacitive soil moisture sensor, comprising:

connecting a capacitive circuit on a biodegradable substrate, wherein the capacitive circuit does not comprise a water-soluble conductor;

connecting an antenna circuit on a biodegradable substrate, wherein a circuit component located between an output of the capacitive circuit and an output of the antenna circuit comprises a degradable conductor that is configured to degrade when exposed to a soil environment; and

encasing the capacitive circuit and the antenna circuit in a hydrophobic, biodegradable encapsulating material.

15 . A method of claim 14 , wherein the capacitive circuit consists of a water-soluble conductor.

16 . The method of claim 14 , wherein encasing the capacitive circuit in the hydrophobic, biodegradable encapsulating material comprises:

identifying a particular encapsulation thickness based at least upon a desired sensitivity of the capacitive soil moisture sensor and a desired life of the capacitive soil moisture sensor; and

encapsulating the capacitive soil moisture sensor in the hydrophobic, biodegradable encapsulating material to the particular encapsulation thickness.

17 . The method of claim 14 , wherein encasing the capacitive circuit in the hydrophobic, biodegradable encapsulating material comprises:

identifying a particular mix ratio of beeswax to soy wax based at least upon a desired life of the capacitive soil moisture sensor; and

encapsulating the capacitive soil moisture sensor in the hydrophobic, biodegradable encapsulating material that comprises the particular mix ratio.

Assignments (2)

Continuity (2)

References Cited (13)