Sensor and monitoring system for structural monitoring

• US 9,267,862 B1
• Filed: 02/17/2010
• Issued: 02/23/2016
• Est. Priority Date: 02/18/2009
• Status: Active Grant

• Current Assignee: SENSR Monitoring Technologies, LLC (Loram Maintenance of Way, Inc.)
• Original Assignee: SENSR Monitoring Technologies, LLC (Loram Maintenance of Way, Inc.)
• Inventors: Kavars, Christopher Lee, Davis, Leslie
• Primary Examiner(s): Toatley, Gregory J
• Assistant Examiner(s): Dalbo, Michael
• Application Number:
  US12/706,880
• Time in Patent Office: 2,197 Days
• Field of Search: 702/160, 735/143.5
• US Class Current: 1/1
• CPC Class Codes: G01M 5/0008 of bridges
• CPC Class Codes: G01M 5/0033 by determining damage, crack or wear
• CPC Class Codes: G01M 5/0066 by exciting or detecting vibration or acceleration vibration testing of structures G01M7/00
• CPC Class Codes: G01P 15/0891 with indication of predetermined acceleration values G01P15/135 takes precedence

Abstract

A method and system for monitoring the integrity of a structure such as a building or a bridge includes taking accelerometer readings using an accelerometer and taking inclinometer readings using an inclinometer. The accelerometer and inclinometer each take readings in at least one axis, with one coincident axis between the two. The accelerometer readings are preferentially sampled at a higher rate than the inclinometer readings. Accelerometer readings verify inclinometer readings, and vice-versa. Using acceleration readings, it can be determined whether, when, and at what frequency inclination readings should be taken. The inclinometer can be powered down as long as accelerometer readings indicate that the environment would strain the inclinometer. Inclinometer readings can also be modified and corrected using inclinometer readings. Data accuracy and reliability are enhanced, and the overall integrity of a structure is dynamically monitored even as the structure and its environment change over time.

Claims

1. A method of monitoring integrity of a structure, including the steps of:

a) obtaining acceleration readings using an accelerometer with a first sensor; and

b) simultaneously obtaining separate inclination readings using an inclinometer with a second sensor that is separate from the first sensor, the inclinometer and the accelerometer being housed in one sensor module;

c) wherein;

1) the inclination readings are obtained at an inclination sampling rate using the second sensor,

2) the acceleration reading are obtained at an accelerometer sampling rate using the first sensor,

3) the accelerometer sampling rate is higher than the inclinometer sampling rate; and

a step of powering down the inclinometer based on acceleration readings, wherein the inclinometer is powered down if the acceleration readings are above a threshold and the inclinometer would be strained or damaged if not powered down.

2. The method of claim 1 further including the step of restoring power to the inclinometer if, based on acceleration readings, it is determined that the inclinometer would not be strained or damaged.

3. A system for monitoring integrity of a structure having a sensor module, wherein:

a) the sensor module includes;

1) a dedicated inclinometer configured to take inclination readings using a first sensor;

(i) along at least two inclinometer axes, and

(ii) at an inclinometer sampling rate; and

2) a dedicated accelerometer configured to take separate acceleration readings using a second sensor that is separate from the first sensor;

(i) along at least three accelerometer axes; and

(ii) at an accelerometer sampling rate;

b) at least one inclinometer axis is coincident with at least one accelerometer axis; and

c) the system is configured to;

1) take inclinometer and acceleration readings simultaneously to discern motion and tilt experienced by a structure being monitored; and

2) use the inclinometer to determine inclination along an inclinometer axis that is not coincident with an accelerometer axis; and

an instructional unit configured to instruct the sensor module to take inclination readings only while acceleration readings fall below a threshold, wherein the inclinometer would be damaged if inclination readings are taken while acceleration readings exceed the threshold;

wherein the accelerometer sampling rate is higher than the inclinometer sampling rate.

4. A system for monitoring integrity of a structure having a sensor module, wherein:

a) the sensor module includes;

1) a dedicated inclinometer configured to take inclination readings using a first sensor;

(i) along at least two inclinometer axes, and

(ii) at an inclinometer sampling rate; and

2) a dedicated accelerometer configured to take separate acceleration readings using a second sensor that is separate from the first sensor;

(i) along at least three accelerometer axes; and

(ii) at an accelerometer sampling rate;

b) at least one inclinometer axis is coincident with at least one accelerometer axis; and

c) the system is configured to;

1) take inclinometer and acceleration readings simultaneously to discern motion and tilt experienced by a structure being monitored; and

2) use the inclinometer to determine inclination along an inclinometer axis that is not coincident with an accelerometer axis;

wherein the system is configured to power down the inclinometer without powering down the accelerometer when the inclinometer would be strained or damaged if not powered down and subsequently restore power to the inclinometer if, based on acceleration readings, the inclinometer would not be strained or damaged.