Non-contacting monitor for bridges and civil structures

• US 20160171309A1
• Filed: 12/09/2015
• Published: 06/16/2016
• Est. Priority Date: 12/11/2014
• Status: Active Grant

• Current Assignee: RDI Technologies, Inc.
• Original Assignee: RDI Technologies, Inc.
• Inventors: Hay, Jeffrey R.
• Granted Patent: US 9,704,266 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 5/0077 Devices for viewing the surface of the body, e.g. camera, magnifying lens
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/165 Evaluating the state of mind, e.g. depression, anxiety
• CPC Class Codes: A61B 5/4815 Sleep quality
• CPC Class Codes: A61B 5/7435 Displaying user selection data, e.g. icons in a graphical user interface
• CPC Class Codes: G01N 2291/028 Material parameters
• CPC Class Codes: G01N 29/44 Processing the detected response signal , e.g. electronic circuits specially adapted therefor digital signal processing per se G06F17/00
• CPC Class Codes: G06F 16/7335 Graphical querying, e.g. query-by-region, query-by-sketch, query-by-trajectory, GUIs for designating a person/face/object as a query predicate end-user interface involving hot spots associated with the video H04N21/4725; end-user interface for selecting a Region of Interest H04N21/4728
• CPC Class Codes: G06F 3/04847 Interaction techniques to control parameter settings, e.g. interaction with sliders or dials
• CPC Class Codes: G06T 2200/24 involving graphical user interfaces [GUIs]
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/20056 Discrete and fast Fourier transform, [DFT, FFT]
• CPC Class Codes: G06T 2207/20216 Image averaging
• CPC Class Codes: G06T 2207/30004 Biomedical image processing
• CPC Class Codes: G06T 2207/30164 Workpiece; Machine component
• CPC Class Codes: G06T 7/0016 involving temporal comparison
• CPC Class Codes: G06T 7/11 Region-based segmentation
• CPC Class Codes: G06T 7/248 involving reference images or patches
• CPC Class Codes: G06T 7/262 : using transform domain methods, e.g. Fourier domain methods
• CPC Class Codes: G06V 20/52 : Surveillance or monitoring of activities, e.g. for recognising suspicious objects recognising microscopic objects G06V20/69
• CPC Class Codes: G06V 40/20 : Movements or behaviour, e.g. gesture recognition recognition of facial expressions G06V40/16
• CPC Class Codes: H04N 7/18 : Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast

Abstract

A method for monitoring the condition of a bridge includes:

• • stably positioning a video camera at a selected location with an unobstructed view of a selected portion of the bridge structure;
  • collecting a video file of the structure over a selected total time interval;
  • using a data processing system to analyze the video and calculate a physical parameter related to movement of the selected portion as a function of time, wherein the data processing system is controlled through a graphical user interface (GUI) having the following features:
    • a display of a single video frame corresponding to a selected time;
    • a movable area selector in the video frame to indicate the selection of an area of the structure for analysis; and,
    • a display of displacement versus time for the selected area over the total time interval.

The processor may perform some tasks, e.g., area selection, autonomously or via predetermined rules.

Claims

1. A method for monitoring the condition of a bridge comprising the steps of:

stably positioning a video camera at a selected location and having an unobstructed view of a selected portion of the bridge structure;

collecting a video file of said structure over a selected total time interval;

using a data processing system to analyze the video and calculate a physical parameter related to movement of said selected portion of said bridge structure as a function of time, wherein said data processing system is controlled through a graphical user interface (GUI) having at least the following features;

a display of a single video frame corresponding to a selected time within said total time interval;

a movable area selector superimposed on said video frame to indicate the selection of an area of said structure for analysis; and

,

a display of displacement versus time for said selected area over said total time interval.

3. The method of claim 1 further including the step of:

populating a searchable database with the video file and selected metadata associated with said video file.

4. The method of claim 1 further including the steps of:

selecting a first area of said structure and calculating a physical displacement associated with said first area;

selecting a second area of said structure and calculating a physical displacement associated with said second area;

comparing the displacements in said first and second areas to determine spatial variations in structural behavior within said bridge.

5. The method of claim 1 further including the steps of:

collecting video files of the same structure at different times; and

,

comparing the displacement of a selected area of said structure at said different times to determine changes in the structural behavior of said bridge over time.

6. The method of claim 1 further including the further of:

collecting a video file while a vehicle of known mass traverses said bridge, and analyzing said video file to provide a calibrated baseline for comparison to files acquired for the same bridge at later times.

8. The method of claim 1 wherein said searchable database includes data sets created by multiple users and is accessible to multiple users so that a larger amount of comparative data is available to each user and a particular bridge may be compared to a larger population of comparable bridges.

9. The method of claim 8 wherein said searchable database resides in the user'"'"'s data processing system and is periodically updated by adding data from other systems and users.

10. The method of claim 8 wherein said searchable database resides in a centralized server accessible to users via any suitable communication means.

11. The method of claim 1 wherein said camera is positioned on the ground at a selected distance from said bridge.

12. The method of claim 1 wherein said camera is positioned on said bridge with an unobstructed view of a portion of the bridge structure.

13. The method of claim 1 wherein said physical parameter related to movement of said selected portion of said bridge structure is selected from the group consisting of:

physical displacement;

frequency;

phase;

maximum displacement; and

damping rate.

14. The method of claim 1 wherein said movable area selector in said GUI comprises a user-generated box of a selected size and shape defining a selected portion of said video frame for analysis.

15. The method of claim 1 wherein said movable area selector in said GUI comprises a user-selected X,Y coordinate and a user-defined set of pixels centered on said X,Y coordinate in said video frame.

16. The method of claim 1 wherein said GUI further allows the user to define a line segment on said video image for use as a reference for measuring displacements and analyzing movement along said line segment.

17. The method of claim 1 wherein said GUI further includes an output selected from the group consisting of:

still images containing phase information;

still images containing frequency information;

still images containing edge enhancement;

moving images displaying motion amplification; and

,

audio recordings.

18. The method of claim 1 wherein said movable area selector is controlled by said data processing system using a rules-based process.

19. The method of claim 18 wherein said data processing system performs an edge detection step and then uses said rules-based process to select areas along said edges for analysis.

2. The method of claim wherein said display of displacement versus time has therein a first movable cursor to allow a user to select a particular time within said total time interval and cause the GUI to display the particular video frame corresponding to that particular time.

7. The method of claim wherein said selected metadata associated with each video file may include data selected from the group consisting of:

specific bridge identifier;

bridge location;

bridge type;

date;

time;

weather conditions;

bridge loading;

traffic conditions;

locations of selected areas analyzed and maximum deflections at said selected areas; and

position of video camera relative to bridge.