DEVICE AND METHOD FOR MEASURING ICE THICKNESS

• US 20130238282A1
• Filed: 07/05/2010
• Published: 09/12/2013
• Est. Priority Date: 07/05/2010
• Status: Active Grant

• Current Assignee: Saab AB
• Original Assignee: Eduardo Figueroa-Karlstrom
• Inventors: Figueroa-Karlstrm, Eduardo
• Granted Patent: US 9,625,248 B2
• Time in Patent Office: Days
• US Class Current: 702/170
• CPC Class Codes: B64D 15/20 Means for detecting icing or initiating de-icing
• CPC Class Codes: G01B 7/06 for measuring thickness measuring during the manufacture of coatings C23C14/54
• CPC Class Codes: G08B 19/02 Alarm responsive to formation or anticipated formation of ice

Abstract

A device and method for measuring ice thickness on a first surface of a construction element. The device includes a sensor arrangement arranged in connection with the construction element and arranged to provide signals related to an impedance. A processing unit is coupled to the sensor arrangement and arranged to determine the presence of ice based on the provided impedance signals. A reference sensor arrangement is arranged to generate reference impedance measurement signals. The processing unit is further arranged to determine the ice thickness based on determinations of a relation between the impedance signals determined by the sensor arrangement and the reference impedance values generated by the reference sensor arrangement.

Claims

1. A device (100) for measuring ice thickness on a first surface (110;

210;

310) of a construction element (120;

220), said device comprising

a sensor arrangement (130) arranged in connection with said construction element and arranged to provide impedance values,

a processing unit (140;

640) coupled to the sensor arrangement (130) and arranged to determine the presence of ice based on the provided impedance values,

characterized in that the device comprises a reference sensor arrangement (150;

450) arranged to generate reference impedance values, and that the processor unit (140;

640) is arranged to determine the ice thickness based on determinations of a relation between the impedance values determined by the sensor arrangement and the reference impedance values generated by the reference sensor arrangement.

2. A device according to claim 1, characterized in that the sensor arrangement (130) comprises one first electrode (134;

234;

334) separated from the construction element (120;

220) by an insulating gap (160;

260;

360), wherein the first electrode (134;

234;

334) has a second surface (132;

232).

3. A device according to claim 2, wherein the construction element (120;

220) forms a grounding electric plane.

4. A device according to claim 2 or 3 characterized in that the electrode (134;

234;

334) is arranged in relation to the construction part so that the second surface (132, 232) and the first surface (110;

210;

310) form an integrated surface.

5. A device according to any of the preceding claims, characterized in that the reference sensor arrangement (150;

450) is arranged to generate substantially the same impedance values as the sensor arrangement when the first and second surfaces are clean.

6. A device according to any of the preceding claims, characterized in that the sensor arrangement (130) and the reference sensor arrangement (150;

450) are operated at the same frequency (AC).

7. A device according to any of the preceding claims, characterized in that the processing unit (140;

640) comprises a calculation unit (642) arranged to calculate a thickness of the ice based on consecutive determinations of the relation between the impedance value and the reference impedance value.

8. A device according to claim 7, characterized in that the calculation unit (642) is arranged to repeatedly calculate a mean value and a standard deviation value for the ice thickness.

9. A device according to claim 7 or 8, characterized in that the calculation unit (642) is implemented in a microprocessor.

10. A device according to any of the preceding claims, characterized in that the processing unit (140;

640) comprises a lock-in amplifier (641) arranged to output the relation between the impedance value and the reference impedance value, said lock-in amplifier being arranged to receive the impedance value and the reference impedance value on its inputs.

11. Method (1000) for measuring ice thickness, said method comprising the steps of

measuring (1010) an impedance change caused by ice accretion as added load to an insulating gap between a construction element (120;

220) and an electrode formed therein,

measuring (1020) a reference impedance, and

determining (1030) the ice thickness based on a correlation between the measured impedance change and the measured reference impedance.