US5686841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and method for the detection and measurement of liquid water and ice layers on the surfaces of solid materials
Assignee: Stolar Inc
•
Filing: 1995-12-13
•
Granted: 1997-11-11
•
Expires: 2015-12-13
Abstract
Abstract An embodiment of the present invention is a roadway sensor for surface installation in a hole such that a thin ceramic contact sensor may be used to measure and cross-compare fundamental physical antenna parameters of the space immediately above a roadway or bridge surface. Measurements are combined by a microprocessor to discriminate between dry pavement, water (rain), snow and ice above the sensor head. Ambient surface temperature, water depth and ice/slush conditions are determined to estimate any hydroplaning hazard and ice/antifreeze/water mixtures. The sensor comprises an antenna that exhibits a resonant frequency and an input admittance including a real term; a Maxwell bridge coupled to the antenna for detecting the resonant frequency, input admittance and real term; and a frequency sweeping oscillator for driving the antenna at a plurality of frequencies proximate in frequency to the resonant frequency. A phase sensitive detector determines an attenuation rate and phase and thereby is able to extract a conductivity (σ) and a dielectric (ε) measurement. The microprocessor relates the conductivity and dielectric measurements to yield, for example, a pair of estimates for ice and water content and layer thickness.
Inventors
- 👤 Larry G. Stolarczyk
- 👤 Gerald Lee Stolarczyk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:39
CPC Classifications
G; G01; G01W; G01W1/00; G01W1/14; G01N; G01N22/00; G01N22/04; G01R; G01R23/00; G01R23/02; G01R23/06; G01R23/07; G08; G08G; G08G1/00; G08G1/09; G08G1/0962; G08G1/0967; G08G1/096766; G08G1/096783
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
88 words
A measurement system, comprising: an antenna for placement proximate to a surface location subject to accumulation of ice and/or water layer and that exhibits a resonant frequency and an input admittance including a real term; Maxwell bridge means coupled to the antenna for detecting said resonant frequency, said input admittance and said real term; and frequency sweeping means for driving the antenna at a plurality of frequencies proximate in frequency to said resonant frequency wherein said resonant frequency, said input admittance and said real term may be determined.
Claim 2
Dependent Claim
88 words
A measurement system, comprising: an antenna for placement proximate to a surface location subject to accumulation of ice and/or water layer and that exhibits a resonant frequency and an input admittance including a real term; Maxwell bridge means coupled to the antenna for detecting said resonant frequency, said input admittance and said real term; and frequency sweeping means for driving the antenna at a plurality of frequencies proximate in frequency to said resonant frequency wherein said resonant frequency, said input admittance and said real term may be determined.
Claim 3
Dependent Claim
53 words
The system of claim 1, further comprising: phase sensitive detection means for determining an attenuation rate and phase and thereby a conductivity (σ) and dielectric (ε) measurement associated with said layer; and computational means for relating said conductivity and dielectric measurements to determine ice and water content, anti-freeze freezing point and layer thickness.
Claim 4
Dependent Claim
17 words
The system of claim 2, further comprising: communication means for conveying said measurements to a radio receiver.
Claim 5
Dependent Claim
32 words
The system of claim 3, wherein: said receiver is adapted for inclusion in an aircraft control tower and includes graphical means for displaying ice build up conditions from an aircraft surface sensor.
Claim 6
Dependent Claim
33 words
The system of claim 3, wherein: said receiver is adapted for inclusion in a motor vehicle and includes graphical means for displaying ice build up conditions to a driver of said motor vehicle.
Claim 7
Dependent Claim
28 words
The system of claim 3, wherein: said receiver is adapted for locating next to a roadway and for activating a sign to alert drivers of a road hazard.
Claim 8
Dependent Claim
59 words
The system of claim 2, wherein the communication means further comprises: frequency/phase modulating means for modulating the frequency sweeping means to apply a modulated radio transmission signal to the sensor antenna wherein the sensor antenna operates as a transmitting antenna between measurements; and coding means for translating said measurements to a modulation signal coupled to the frequency modulating means.
Claim 9
Dependent Claim
33 words
The system of claim 1, further comprising: a battery for powering the system; and automatic power-up and power-standby means for periodically cycling the system wherein average power drain from the battery is reduced.
Claim 10
Dependent Claim
32 words
The system of claim 8, further comprising: temperature sensing means for providing a surface temperature such that a freezing point may be determined and to control the automatic power-up and power-standby means.
Claim 11
Dependent Claim
21 words
The system of claim 1, further comprising: temperature sensing means for determining a temperature of said surface proximate to the antenna.
Claim 12
Dependent Claim
44 words
The system of claim 7, further comprising: a housing for the system for embedding the system flush in a roadway wherein roadway water depth and ice/slush conditions may be determined to periodically communicate any hydroplaning hazard and ice/antifreeze/water mixtures information to a radio receiver.
Claim 13
Dependent Claim
36 words
The system of claim 7, further comprising: a housing for the system for embedding the airfoil surfaces of an airplane wing wherein icing conditions may be determined and the information periodically communicated to a radio receiver.
Claim 14
Dependent Claim
68 words
The system of claim 7, further comprising: a battery for powering the system; automatic power-up and power-standby means for periodically cycling the system wherein average power drain from the battery is reduced; a housing for the system for embedding the system flush in a surface subject to weather conditions wherein water depth and ice/slush conditions may be determined to periodically communicate ice/antifreeze/water mixture information to a radio receiver.
Claim 15
Dependent Claim
28 words
The system of claim 1, wherein: the antenna comprises materials having a thermal conductivity that approximates the thermal conductivity of a material which substantially comprises said surface location.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-11-10 | 2001-05-12 | 2001-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-11-10 | 2005-05-12 | 2005-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-11-10 | 2009-05-12 | 2009-11-11 | $7700.00 | Window Closed / Lapsed |