Claims
- 1. A paving material analyzer system comprising:
an electronic circuit including an inductor adapted to null a capacitive reactance portion of an impedance reading of the paving material leaving a non-reactive portion; and a data analyzer operatively coupled to the electronic circuit that determines:
a total impedance of the paving material based on the non-reactive portion, a known inductive reactance and a known operating frequency of the electronic circuit, and a density of the paving material based on the total impedance.
- 2. The system of claim 1, wherein the inductor includes an active operational amplifier circuit.
- 3. The system of claim 1, further comprising a sensor operatively coupled to the electronic circuit, wherein an electric field is generated from the sensor proximate the paving material by the electronic circuit.
- 4. The system of claim 1, wherein the data analyzer corrects the density indication for an impedance of the sensor.
- 5. The system of claim 1, wherein the data analyzer includes a moisture corrector that corrects for moisture on a top surface of the paving material.
- 6. The system of claim 5, wherein the moisture corrector determines a density moisture correction factor from a phase angle of the impedance of the paving material.
- 7. The system of claim 1, further comprising a standoff distance corrector that corrects the density for a distance of the sensor to the paving material.
- 8. The system of claim 1, wherein the electronic circuit includes a variable oscillator.
- 9. A paving material analyzer system comprising:
means for measuring an impedance of the paving material and nulling a capacitive reactance portion of the impedance; means for analyzing data operatively coupled to the means for measuring, the means for analyzing determining:
a total impedance of the paving material based on a non-reactive portion of the impedance, a known inductive reactance portion of the impedance and a known operational frequency of the means for measuring, and a density of the paving material based on the total impedance.
- 10. The system of claim 9, wherein the means for determining includes a means for varying an operating frequency.
- 11. A method for analyzing paving material comprising the steps of:
determining an impedance of the paving material; determining a capacitance of a space between a sensor and the paving material; and determining the density of the paving material based on the impedance determination of the paving material and the capacitance of the space.
- 12. The method of claim 11, wherein the step of determining an impedance of the paving material includes:
providing a sensor; applying an electric potential to the sensor to generate an electrical field proximate the paving material; receiving the electrical field from the paving material; and determining an impedance of the paving material based on the effect of impedance characteristics of the paving material on the electrical field.
- 13. The method of claim 12, wherein the step of determining the impedance of the paving material includes nulling a capacitive reactance portion of the impedance.
- 14. The method of claim 11, wherein the step of determining an impedance of the paving material includes correcting the determination for an impedance of the sensor.
- 15. The method of claim 11, wherein the step of determining an impedance of the paving material includes correcting the determination for moisture on a top surface of the paving material.
- 16. The method of claim 15, wherein the step of correcting includes monitoring a phase angle of the impedance to determine moisture on a top surface of the paving material.
- 17. A paving material analyzer system having a sensor operatively couple to an electronic circuit for generating an electric field proximate paving material and a data analyzer for determining a density of the paving material, the system comprising:
a standoff distance corrector that corrects the density for a distance of the sensor to the paving material.
- 18. The system of claim 17, wherein the standoff distance corrector includes means for measuring the distance of the sensor to the paving material.
- 19. The system of claim 17, wherein the standoff distance corrector includes a laser probe.
- 20. The system of claim 19, wherein the standoff distance corrector also determines a paving material surface profile.
- 21. The system of claim 17, wherein the standoff distance corrector includes a paving material contact and a Hall effect sensor coupled thereto.
- 22. The system of claim 17, wherein the electronic circuit includes means for determining an impedance of the paving material and nulling a capacitive reactance portion of the impedance.
Parent Case Info
[0001] This application is a continuation-in-part application of U.S. Ser. No. 09/565,022, to be issued Jul. 2, 2002 as U.S. Pat. No. 6,414,497.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09565022 |
May 2000 |
US |
Child |
10185510 |
Jun 2002 |
US |