Coating impedance monitoring system

• US 7,477,060 B2
• Filed: 12/27/2005
• Issued: 01/13/2009
• Est. Priority Date: 12/27/2005
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Matthews, Michael R., Shreve, Gary A., Yu, Steven Y.
• Primary Examiner(s): Patel; Harshad
• Assistant Examiner(s): ROY, PUNAM P
• Application Number:
  US11/318,709
• Publication Number:
  US 20070144272A1
• Time in Patent Office: 1,113 Days
• Field of Search: 324/700, 324/699, 324/693, 324/691, 324/649, 324/600, 702/33, 702/34, 702/35, 702/36
• US Class Current: 324/693
• CPC Class Codes: G01N 17/02 Electrochemical measuring systems for weathering, corrosion or corrosion-protection measurement
• CPC Class Codes: G01N 33/44 Resins; rubber; leather

Abstract

A detection system for monitoring an engineered structure includes an array of sensors disposable in a predetermined pattern on the engineered structure and disposable between a surface of the engineered structure and a protective coating substantially covering the surface. The detection system also includes a data acquisition system in communication with the array of sensors for retrieving data from the sensors. The array of sensors can provide data corresponding to at least one of a degree of cure of the protective coating, a health of the cured protective coating, and a corrosion rate of the engineered structure at each of the sensors.

Claims

1. A detection system for monitoring a physical condition of an engineered structure, comprising:

an array of sensors disposable in a predetermined pattern on the engineered structure and disposable between a surface of the engineered structure and a protective coating substantially covering said surface; and

a data acquisition system in communication with the array of sensors for retrieving data from said sensors, the array of sensors providing data corresponding to at least one of a degree of cure of the protective coating and a corrosion rate of the engineered structure at each of the sensors,

wherein at least one sensor of the array comprises;

a sensing portion configured to detect at least one of an impedance, current, and voltage, said sensing portion disposed on a flexible substrate, and

a control electronics portion including a unique address,

wherein the sensing portion comprises a conductive element patterned as at least two electrodes on the flexible substrate, and wherein the control electronics portion includes voltage and current control electronics.

2. The detection system of claim 1, wherein the sensing portion is disposable on a non-flat surface of the engineered structure.

3. The detection system of claim 1, wherein at least a portion of the plurality of sensors of the sensor array are coupled serially.

4. The detection system of claim 1, wherein at least a portion of the plurality of sensors of the sensor array are coupled in parallel.

5. The detection system of claim 1, wherein the array of sensors are coupled to the data acquisition system via a data line.

6. The detection system of claim 1, wherein the engineered structure comprises at least one of a metallic, composite, ceramic, and fiberglass material.

7. A method of detecting physical conditions in an engineered structure:

providing a data acquisition circuit that provides an activation signal initiating data collection from an array of sensors, each of the sensors including a sensing portion, the array of sensors being disposed between a surface of the engineered structure and a protective coating substantially covering said surface;

searching for at least a portion of the array of sensors and recording and saving all searched sensor addresses;

retrieving data from a first sensor of the searched sensors;

analyzing the retrieved data;

storing the analyzed data; and

displaying the stored data upon request, wherein the analyzed data corresponding to at least one of a degree of cure of the protective coating and a corrosion rate of the engineered structure at each of the sensors, wherein the activation signal provides power to each of the sensors of the array.

8. The detection method of claim 7, further comprising repeating the retrieval, analyzing, and storing steps for a second sensor of the array.

9. The detection method of claim 7, further comprising providing an alert when the sensor indicates that one of a degradation of the coating and a degradation of the structure has occurred.

10. The detection method of claim 7, further comprising turning off the power to the sensors.

11. The detection method of claim 7, comprising detecting a first voltage across a sensing portion of the first sensor and detecting a second voltage at the first sensor wherein the second voltage corresponds to a voltage supplied by the data acquisition circuit, and calculating a ratio of the first voltage and a second voltage.