Erosion sensor and system, method, and computer program product thereof

• US 10,215,660 B1
• Filed: 11/10/2011
• Issued: 02/26/2019
• Est. Priority Date: 11/10/2011
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Kraft, William, Basak, Leszek S., Fouts, Timothy R.
• Primary Examiner(s): Nghiem, Michael P
• Application Number:
  US13/294,015
• Time in Patent Office: 2,665 Days
• Field of Search: 702 34, 702 35
• CPC Class Codes: G01M 5/0033 by determining damage, crack or wear
• CPC Class Codes: G01M 99/007 by applying a load, e.g. for resistance or wear testing G01M99/001 takes precedence; testing the elasticity of structures G01M5/00
• CPC Class Codes: G05B 19/4065 Monitoring tool breakage, life or condition
• CPC Class Codes: G05B 23/02 Electric testing or monitoring

Abstract

Erosion sensors and systems, methods, and computer products thereof are operative to determine and provide real time erosion data. Such data may be used to determine in real time an amount of erosion or ablation on an ablative surface, for instance, of a rocket or missile launch pad, of an exhaust management system, of an extraterrestrial vehicle, or of a fire detection system.

Claims

1. An ablation detection system for detecting ablation caused by high temperature, high pressure exhaust, comprising:

at least one ablative panel, the at least one ablative panel having embedded therein a plurality of fiber optic sensors, each configured to provide a return signal having an output level inversely proportional to an amount of ablation sustained by the respective sensor due to exposure to the high temperature, high pressure exhaust;

a receiver to detect return signal output characteristics from the fiber optic sensors, the return signal output characteristics being indicative of the amount of ablation sustained by the fiber optic sensors due to exposure to the high temperature, high pressure exhaust,

the receiver being operative to calculate the amount of ablation based on the detected return signal output characteristics, and

the receiver being operative to output an identifier when the amount of ablation exceeds a predetermined threshold, the identifier indicating which of the plurality of fiber optic sensors have ablated past the predetermined threshold; and

a control unit operative to receive ablation data associated with the amount of ablation from the receiver, each of the plurality of fiber optic sensors being associated with a respective one of a plurality of launch cells and the control unit being operative to perform one or more operations based on the ablation data, the one or more operations including at least one of;

determining a sequence of operations, determining a next operation to take, generating an erosion model, determining existence of an unsafe condition, determining that a portion should be replaced or refurbished, outputting an alarm, performing calibration operations, and outputting data to a display,

wherein each of the fiber optic sensors includes a plurality of discrete optic fibers configured to pass light therethrough, the plurality of discrete optic fibers being disposed in a body portion of a respective one of the fiber optic sensors, and

wherein each fiber optic sensor comprises a body made of an ablative material, a top face of the body being flush with a front face of the at least one ablative panel such that the top face is exposed to an external environment prior to ablation of the fiber optic sensor.

2. The ablation detection system according to claim 1, wherein the return signal output characteristics include an amount of light.

3. The ablation detection system according to claim 1, wherein the at least one ablative panel has the plurality of fiber optic sensors substantially permanently embedded therein.

4. The ablation detection system according to claim 1, wherein said receiver is a transceiver and outputs a signal to an input of the fiber optic sensors, the signal being a plurality of discrete light signals.

5. The ablation detection system according to claim 1, wherein said receiver is operative to perform a calibration operation to determine a return signal output characteristic of the fiber optic sensors indicative of no or substantially no ablation, the return signal output characteristic indicative of no or substantially no ablation being used by said receiver for comparison against return signal output characteristics in a normal operation mode to determine the amount of ablation.

6. The ablation detection system according to claim 1, wherein ablation to the fiber optic sensors is caused by a force or forces other than a mechanical friction force, and wherein said receiver is operative to calculate a thickness of and/or an amount of thickness reduction of at least one ablative panel in which at least one of the fiber optic sensors is embedded.

7. The ablation detection system according to claim 1, wherein the receiver is further operative to output an alarm when the amount of ablation exceeds the predetermined threshold.

8. The ablation detection system of claim 1, wherein the return signal is based on light passing through the fiber optic sensors.

9. The ablation detection system of claim 1, wherein the one or more operations comprise determining whether a cell is safe for firing, a cell firing order, and/or a next cell to fire of the launch cells.

10. The ablation detection system of claim 9,

wherein the launch cells are vertical launch cells, and

wherein each of the plurality of fiber optic sensors is embedded in a surface of a respective one of the plurality of vertical launch cells.

11. The ablation detection system of claim 1, wherein each of the discrete optic fibers are disposed in a semi-rectangular arrangement.

12. The ablation detection system of claim 1, wherein

the body made of the ablative material is adapted to measure ablation caused by a force other than mechanical friction including ablation caused by high temperature, high pressure exhaust.

13. The ablation detection system of claim 12, wherein the ablative material is one or more of MXB 360, MXBE-350, FR-1, CD108-40, FM16771-F, FM16771-A, and MX-4926.

14. The ablation detection system of claim 1, wherein the control unit either includes a non-volatile memory or is operatively coupled to a non-volatile memory, the control unit storing the received ablation data in the non-volatile memory, the stored ablation data being used to perform refurbishing calculations to determine whether one or more components of the system should be refurbished or replaced.

15. The ablation detection system of claim 1, wherein the plurality of fiber optic sensors protrude above a surface of the at least one ablation panel.