Removable chromatic witness assembly, system, and method to monitor thermal events and impact events on a composite structure

Patent metadata

Field	Value
Publication number	US-10024792-B2
Application number	US-201615231691-A
Country	US
Kind code	B2
Filing date	Aug 8, 2016
Priority date	Aug 8, 2016
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

There is provided a removable chromatic witness assembly, system, and method to monitor thermal events and impact events on a surface of a composite structure. The removable chromatic witness assembly has a plurality of chromatic witness geometric configurations separately coupled in an arrangement to one or more portions of a polymeric film layer. Each chromatic witness geometric configuration has a plurality of chromatic probes of a same type incorporated into an adhesive material. At least two of the geometric configurations have a different type of chromatic probes with a different sensing capability for thermal events and impact events on the composite structure. The polymeric film layer and the geometric configurations form the removable chromatic witness assembly in a form of a removable chromatic witness applique configured to be removably applied directly and continuously to the surface of the composite structure, and configured to monitor the thermal and impact events.

First claim

What is claimed is:

1. A removable chromatic witness assembly to monitor thermal events and impact events on a surface of a composite structure, the removable chromatic witness assembly comprising:
a plurality of chromatic witness geometric configurations separately coupled in an arrangement to one or more portions of a polymeric film layer, each chromatic witness geometric configuration comprising a plurality of chromatic probes of a same type incorporated into an adhesive material, and at least two of the plurality of chromatic witness geometric configurations having a different type of chromatic probes with a different sensing capability for one of, thermal events and impact events on the surface of the composite structure,
wherein the polymeric film layer and the plurality of chromatic witness geometric configurations form the removable chromatic witness assembly in a form of a removable chromatic witness applique configured to be removably applied directly and continuously to the surface of the composite structure, and configured to monitor the thermal events and the impact events on the surface of the composite structure.

2. The removable chromatic witness assembly of claim 1 further comprising a backing film layer and a pressure sensitive adhesive (PSA) layer, the backing film layer coupled to the plurality of chromatic witness geometric configurations, and the pressure sensitive adhesive (PSA) layer coupled to the backing film layer.

3. The removable chromatic witness assembly of claim 1 wherein the polymeric film layer is transparent and comprises a high temperature polymeric film layer that is stable in a temperature range of between about 130° F. (one hundred thirty degrees Fahrenheit) to about 500° F. (five hundred degrees Fahrenheit).

4. The removable chromatic witness assembly of claim 1 wherein the plurality of chromatic witness geometric configurations comprise three repeating chromatic witness geometric configurations, each of the three repeating chromatic witness geometric configurations having different types of chromatic probes.

5. The removable chromatic witness assembly of claim 1 wherein the plurality of chromatic witness geometric configurations are separately coupled in an adjacent repeating arrangement to the one or more portions of the polymeric film layer, and further wherein each chromatic witness geometric configuration has a geometric configuration comprising one of, a rectangular strip, and a square configuration.

6. The removable chromatic witness assembly of claim 1 wherein the plurality of chromatic probes comprise one of, thermochromatic probes and mechanochromatic probes.

7. The removable chromatic witness assembly of claim 1 wherein the adhesive material comprises a pressure sensitive adhesive (PSA) comprising one or more of a silicone adhesive, an acrylic adhesive, and an epoxy adhesive.

8. The removable chromatic witness assembly of claim 1 wherein the removable chromatic witness applique is a multi-sensing applique configured to take thermal testing measurements and impact testing measurements across the surface of the composite structure over which the removable chromatic witness applique is applied, and wherein after the composite structure is tested, the removable chromatic witness applique is configured to be removed and is configured to be analyzed.

9. A removable chromatic witness system to monitor thermal events and impact events on a surface of a composite structure to be tested and monitored, the removable chromatic witness system comprising:
the composite structure having the surface to be tested and monitored for one of, the thermal events and the impact events;
a removable chromatic witness assembly comprising a removable chromatic witness applique applied directly and continuously over the surface of the composite structure to be tested and monitored, the removable chromatic witness assembly comprising a plurality of chromatic witness geometric configurations separately coupled in a repeating arrangement to one or more portions of a polymeric film layer, each chromatic witness geometric configuration comprising a plurality of chromatic probes of a same type incorporated into an adhesive material, and at least two of the plurality of chromatic witness geometric configurations having a different type of chromatic probes with a different sensing capability for sensing one of, the thermal events and the impact events on the surface of the composite structure;
a light source configured to activate the plurality of chromatic probes in the removable chromatic witness applique applied on the surface of the composite structure, wherein each different type of chromatic probe is configured to fluoresce in a different predefined time-temperature range;
an imaging device configured to image and record one or more images of a chromatic response of the different types of chromatic probes to the light source, the chromatic response comprising one or more color changes and one or more intensity changes; and
a data processor system configured for processing and analyzing the one or more images to identify areas on the surface of the composite structure that have experienced one of, temperatures above a predefined threshold temperature, and impacts above a predefined threshold impact, based on the chromatic response.

10. The removable chromatic witness system of claim 9 wherein the removable chromatic witness assembly further comprises a backing film layer and a pressure sensitive adhesive (PSA) layer, the backing film layer coupled to the plurality of chromatic witness geometric configurations, and the pressure sensitive adhesive (PSA) layer coupled to the backing film layer.

11. The removable chromatic witness assembly of claim 9 wherein the plurality of chromatic witness geometric configurations comprise three repeating chromatic witness geometric configurations, each of the three repeating chromatic witness geometric configurations having different types of chromatic probes.

12. The removable chromatic witness system of claim 9 wherein the light source comprises one of, an ultraviolet (UV) light source, a light-emitting diode (LED) light source, and an infrared (IR) light source, and further wherein the imaging device comprises one of, a detector, including a spectrometer, and a camera, including a digital camera.

13. The removable chromatic witness system of claim 9 wherein the composite structure comprises an aircraft composite structure, and the removable chromatic witness applique is a multi-sensing applique configured to take thermal testing measurements and impact testing measurements across the surface of the composite structure over which the removable chromatic witness applique is applied, and wherein after the composite structure is tested, the removable chromatic witness applique is configured to be removed and is configured to be analyzed.

14. A method of using a removable chromatic witness system to monitor thermal events and impact events on a surface of a composite structure, the method comprising the steps of:
providing the removable chromatic witness system comprising:
the composite structure having the surface to be tested and monitored for one of, thermal events and impact events;
a removable chromatic witness assembly comprising a removable chromatic witness applique having a plurality of chromatic witness geometric configurations separately coupled in an arrangement to one or more portions of a polymeric film layer, each chromatic witness geometric configuration comprising a plurality of chromatic probes of a same type incorporated into an adhesive material, and at least two of t

Assignees

• Boeing Co
• Univ Washington

Inventors

• Toivola Ryan E
• Jen Alex Kwan-Yue
• Jang Sei-Hum
• Flinn Brian D
• Winter Eric G
• Georgeson Gary E
• Holman Wesley L
• Gleason Gregory R
• Johnston Scott R

Classifications

• B32B27/322

  comprising halogenated polyolefins, e.g. PTFE · CPC title

• B32B27/08

  of synthetic resin · CPC title

• B32B2307/748

  Releasability · CPC title

• B32B2250/242

  All polymers belonging to those covered by group B32B27/32 · CPC title

• B32B2307/308

  Heat stability · CPC title