Moisture detection system and method of use thereof

A moisture detection system comprising:

• an electrical conductor disposed on a surface of a substrate and having a resonant frequency that varies as a function of an amount of moisture present adjacent the electrical conductor;
• an oscillator which outputs an oscillator signal at a predetermined amplitude and a predetermined frequency;
• a resonator circuit coupled to the electrical conductor and responsive to the oscillator signal for outputting a resonator signal having an amplitude related to the resonant frequency of the electrical conductor;
• a filter circuit responsive to the resonator signal for outputting a rectified and filtered signal;
• an analog-to-digital converter responsive to the rectified and filtered signal for outputting a digital signal related to the rectified and filtered signal;
• and
• a controller responsive to the digital signal for causing another system to operate in accordance with the digital signal, wherein the predetermined frequency is between one of (i) 300 and 700 kHz and (ii) 400 and 600 kHz.

A moisture detection system comprising:

• an electrical conductor disposed on a surface of a substrate and having a resonant frequency that varies as a function of an amount of moisture present adjacent the electrical conductor;
• an oscillator which outputs an oscillator signal at a predetermined amplitude and a predetermined frequency;
• a resonator circuit coupled to the electrical conductor and responsive to the oscillator signal for outputting a resonator signal having an amplitude related to the resonant frequency of the electrical conductor;
• a filter circuit responsive to the resonator signal for outputting a rectified and filtered signal;
• an analog-to-digital converter responsive to the rectified and filtered signal for outputting a digital signal related to the rectified and filtered signal;
• and
• a controller responsive to the digital signal for causing another system to operate in accordance with the digital signal, wherein:
• the substrate is a flexible substrate;
• and
• the flexible substrate further includes at least one of (i) a ground conductor disposed on the flexible substrate at least partially surrounding the electrical conductor and (ii) a conductive material disposed on a surface of the flexible substrate opposite the electrical conductor, said conductive material having a form that defines a faraday shield.

A moisture detection system comprising:

• an electrical conductor disposed on a surface of a substrate and having a resonant frequency that varies as a function of an amount of moisture present adjacent the electrical conductor;
• an oscillator which outputs an oscillator signal at a predetermined amplitude and a predetermined frequency;
• a resonator circuit coupled to the electrical conductor and responsive to the oscillator signal for outputting a resonator signal having an amplitude related to the resonant frequency of the electrical conductor;
• a filter circuit responsive to the resonator signal for outputting a rectified and filtered signal;
• an analog-to-digital converter responsive to the rectified and filtered signal for outputting a digital signal related to the rectified and filtered signal;
• and
• a controller responsive to the digital signal for causing another system to operate in accordance with the digital signal, wherein the filter circuit includes:
• a diode connected to conduct current from the resonator toward the analog-to-digital converter;
• and
• a capacitor connected between an end of the diode adjacent the analog-to-digital converter and a reference voltage.

A moisture detector system comprising:

• means disposed on a substrate for conducting electrical current, the conducting means having a resonant frequency that changes as a function of moisture adjacent the conducting means;
• an oscillator for outputting to the conducting means an oscillator signal having a predetermined frequency and a first amplitude;
• means responsive to the oscillator signal for outputting a resonator signal having a second amplitude related to the resonant frequency of the conducting means, wherein the second amplitude is different than the first amplitude;
• and
• means responsive to the resonator signal for outputting a control signal having a value related to the second amplitude of the resonator signal.

A moisture detector system comprising:

• means disposed on a substrate for conducting electrical current, the conducting means having a resonant frequency that changes as a function of moisture adjacent the conducting means;
• an oscillator for outputting to the conducting means an oscillator signal having a predetermined frequency and a first amplitude;
• means responsive to the oscillator signal for outputting a resonator signal having a second amplitude related to the resonant frequency of the conducting means, wherein the second amplitude is different than the first amplitude;
• and
• means responsive to the resonator signal for outputting a control signal having a value related to the second amplitude of the resonator signal, wherein the conducting means includes at least one of (i) one or more lines of conductive material, (ii) one or more sheets of conductive material, and (iii) a dispersion of conductive particles in the form of one or more lines and/or sheets.

A moisture detector system comprising:

• means disposed on a substrate for conducting electrical current, the conducting means having a resonant frequency that changes as a function of moisture adjacent the conducting means;
• an oscillator for outputting to the conducting means an oscillator signal having a predetermined frequency and a first amplitude:
• means responsive to the oscillator signal for outputting a resonator signal having a second amplitude related to the resonant frequency of the conducting means, wherein the second amplitude is different than the first amplitude;
• and
• means responsive to the resonator signal for outputting a control signal having a value related to the second amplitude of the resonator signal, wherein the substrate is a windshield that includes plural sheets of glass laminated together.

A moisture detector system comprising:

• means disposed on a substrate for conducting electrical current, the conducting means having a resonant frequency that changes as a function of moisture adjacent the conducting means;
• an oscillator for outputting to the conducting means an oscillator signal having a predetermined frequency and a first amplitude;
• means responsive to the oscillator signal for outputting a resonator signal having a second amplitude related to the resonant frequency of the conducting means, wherein the second amplitude is different than the first amplitude;
• and
• means responsive to the resonator signal for outputting a control signal having a value related to the second amplitude of the resonator signal, wherein:
• the substrate is a flexible substrate that is coupled to a sheet;
• and
• the conducting means has a resonant frequency that changes as a function of moisture on the sheet.

A method of moisture detection comprising:

• (a) providing a substrate having an electrical conductor disposed thereon;
• (b) stimulating the electrical conductor with an oscillator signal in the absence of moisture adjacent the electrical conductor;
• (c) determining a first amplitude of the electrical conductor to the stimulation in step (b);
• (d) stimulating the electrical conductor with the oscillator signal when moisture is present adjacent the electrical conductor;
• (e) determining a second amplitude of the electrical conductor to the stimulation in step (d), wherein the second amplitude is different than the first amplitude due to a change in resonant frequency of the electrical conductor in response to the presence of moisture adjacent the electrical conductor;
• and
• (f) determining a difference between the first amplitude and the second amplitude, wherein the difference is related to the amount of moisture present adjacent the electrical conductor.

A moisture detection system comprising:

• a substrate;
• an electrical conductor disposed on the substrate;
• means for stimulating the electrical conductor with an oscillator signal operating at a predetermined frequency;
• means responsive to the oscillator signal and the electrical conductor for detecting changes in resonant frequency of the electrical conductor in response to changes in an amount of moisture disposed adjacent the electrical conductor;
• and a controller responsive to the frequency changes for causing another system to operate in accordance with the changes.

A moisture detection system comprising:

• a substrate;
• an electrical conductor disposed on the substrate;
• means for stimulating the electrical conductor with an oscillator signal;
• means responsive to the oscillator signal and the electrical conductor for detecting changes in a resonant frequency of the electrical conductor in response to changes in an amount of moisture disposed adjacent the electrical conductor;
• a controller responsive to the frequency changes for causing another system to operate in accordance with the changes;
• and a sheet in contact with the substrate.

A moisture detection system comprising:

• a fluid reservoir, an electrical conductor disposed on the fluid reservoir;
• means for stimulating the electrical conductor with an oscillator signal;
• means for stimulating the electrical conductor with an oscillator signal;
• means responsive to the oscillator signal and the electrical conductor for detecting a change in a resonant frequency of the electrical conductor responsive to a change in a level of fluid in the fluid reservoir and for outputting a control signal when the detected change in the resonant frequency of the electrical conductor corresponds to less than a desired level of fluid in the fluid reservoir;
• and a controller responsive to the frequency changes for causing another system to operate in accordance with the changes.