Sensor Infrastructure

• US 20080312846A1
• Filed: 03/03/2008
• Published: 12/18/2008
• Est. Priority Date: 03/03/2004
• Status: Active Grant

• Current Assignee: Metis Design Corporation
• Original Assignee: Metis Design Corporation
• Inventors: Kessler, Seth S., Jugenheimer, Kristin A., Size, Aaron B.
• Granted Patent: US 7,725,269 B2
• Time in Patent Office: Days
• US Class Current: 702/35
• CPC Class Codes: G01B 5/30 for measuring the deformation in a solid, e.g. mechanical strain gauge
• CPC Class Codes: G01L 1/16 using properties of piezoelectric devices
• CPC Class Codes: G01M 5/0033 by determining damage, crack or wear
• CPC Class Codes: G01M 5/0075 by means of external apparatus, e.g. test benches or portable test systems G01M5/005 takes precedence
• CPC Class Codes: G01N 2291/0258 Structural degradation, e.g. fatigue of composites, ageing of oils
• CPC Class Codes: G01N 2291/02827 Elastic parameters, strength or force
• CPC Class Codes: G01N 2291/02845 Humidity, wetness
• CPC Class Codes: G01N 2291/0422 Shear waves, transverse waves, horizontally polarised waves
• CPC Class Codes: G01N 2291/0427 Flexural waves, plate waves, e.g. Lamb waves, tuning fork, cantilever
• CPC Class Codes: G01N 2291/106 one or more transducer arrays
• CPC Class Codes: G01N 2291/2694 Wings or other aircraft parts
• CPC Class Codes: G01N 29/045 by imparting shocks to the workpiece and detecting the vibrations or the acoustic waves caused by the shocks measuring resonant frequency G01H13/00; measuring strength properties by application of mechanical stress G01N3/00
• CPC Class Codes: G01N 29/12 by measuring frequency or resonance of acoustic waves measuring frequency or resonant frequency of mechanical vibrations or acoustic waves in general G01H1/06, G01H3/04, G01H13/00; acoustic resonators G10K11/04; vibration or shock testing of structures G01M7/00
• CPC Class Codes: G01N 29/2475 Embedded probes, i.e. probes incorporated in objects to be inspected
• CPC Class Codes: G01N 29/2481 Wireless probes, e.g. with transponders or radio links

Abstract

A device for use in detecting an event in a structure includes a sensor encapsulation, the encapsulation containing a sensor, an actuator positioned substantially in-plane to the sensor within the housing and a printed circuit board in communication with at least one of the sensor and the actuator. The printed circuit board includes a microprocessor constructed and arranged to collect data from at least one of the sensor and the actuator, a signal generator constructed and arranged to provide excitation to at least one of the sensor and the actuator, and an amplifier to condition the excitation.

Claims

1. A network of nodes for use in detecting an event in a structure, each node in the network comprising:

a sensor encapsulation configured for structural health monitoring, the encapsulation containing;

at least one sensing element;

a printed circuit board coupled to the at least one sensing element, the printed circuit board comprising;

a signal conditioning analog circuit;

an analog-to-digital conversion element configured to digitize data collected from the at least one sensing element;

a microprocessor coupled to the at least one sensing element, the signal conditioning analog circuit, and the analog-to-digital conversion element and configured to collect data from the at least one sensing element;

an excitation element configured to provide excitation to the sensing element;

a memory component coupled to the microprocessor configured to locally store data; and

a communication chip coupled to the microprocessor and configured to provide remote digital connectivity.

2. The network of claim 1 wherein the sensing element includes a sensor that measures at least one of stress, strain, vibration, acoustics, temperature, humidity, pressure, acceleration, location, rotation, radiation, electric fields, magnetic fields, light and motion.

3. The network of claim 1 wherein the sensor encapsulation further comprises a connector to provide a power and a data connection between the device and an external network.

4. The network of claim 1 wherein the sensor encapsulation further comprises a wireless chip positioned in the encapsulation and configured to provide a data connection between the node and an external network.

5. The network of claim 1 wherein the node is configured to bi-directionally communicate with an external microprocessor.

6. The network of claim 1 wherein each node of the network is configured to communicate with a second node in the network.

7. The network of claim 6 wherein a first node of the network is configured to pass data associated with the first node to a second node of the network.

8. The network of claim 1 wherein each of the nodes of the network is configured to pass data to a central processing unit.

9. The network of claim 8 wherein the encapsulation further comprises a USB connector and wherein the USB connector is configured to connect each node and the central processing unit.

10. The network of claim 8 wherein the central processing unit is configured to trigger an active damage detection operation by communicating with at least one of the plurality of nodes.

11. The network of claim 1 wherein the encapsulation further comprises a battery to supply power to the device.

12. The network of claim 1 wherein the encapsulation further comprises an actuator positioned substantially in-plane with the at least one sensing element.

13. The network of claim 12 wherein the encapsulation further comprises an amplifier configured to condition and rectify an excitation signal provided to the excitation element.

14. The network of claim 1 wherein the excitation element is configured to indirectly provide excitation to the sensing element.

15. The network of claim 1 wherein the excitation element is configured to directly provide excitation to the sensing element.

16. A method of detecting an occurrence in a material, the method comprising:

distributing a plurality of sensor nodes in a structure, each of the sensor nodes having an analog-to-digital conversion element, a sensing element, an excitation element, and a microprocessor;

exciting the sensing element using the excitation element;

collecting data related to the structure from at least one of the plurality of nodes using the sensing element;

analyzing the data to identify a structural occurrence in the structure by comparing the data to a baseline measurement of the structure; and

triggering an active damage detection operation to determine a location and a degree of the structural occurrence.

17. The method of claim 16 further comprising digitizing data collected from at least one of the plurality of nodes.

18. The method of claim 16 further comprising collecting data at a node proximal to the at least one of the plurality of nodes before analyzing the data to identify a structural occurrence.

19. The method of claim 16 further comprising passing the data to a central processor for analysis of the data to identify a structural occurrence.

20. The method of claim 16 further comprising iteratively collecting data at the at least one of the plurality of nodes and passing the data to at least one of a second node and a central processing unit.

21. The method of claim 16 further comprising:

passing the data collected at a first of the plurality of nodes to a second node;

combining the data from the first node with data collected at the second node; and

determining a position of a structural occurrence based on the data from the first node and the data from the second node.

22. The method of claim 16 wherein exciting the sensing element includes indirectly exciting the sensing element using the excitation element.

23. The method of claim 16 wherein exciting the sensing element includes directly exciting the sensing element using the excitation element.