CN104597126B - Method for detecting structure health of spacecraft based on acoustic sensor - Google Patents

Abstract

The invention discloses a method for detecting structure health of a spacecraft based on an acoustic sensor. The method is characterized in that an acoustic transmission signal is synchronously acquired by various sensors on the spacecraft, and the acoustic transmission signal is transmitted to a signal acquisition analyzer after being amplified and filtered. The signal acquisition analyzer is used for processing the signal, whether a collision happens or not is firstly judged, a collision point is located if the collision happens, simultaneously a leakage detection and location module is started to detect and locate the leakage, and then a flaw detection module is started to detect the damage degree of the nearby structure according to the collision and leakage location result. By adopting the method, the structure of a spacecraft bin body does not need to be changed, the operation of an astronaut outside the spacecraft bin is not needed, the area of 4m<2> surrounding the sensor can be monitored in real time, the surface of the spacecraft bin body does not need to be gradually scanned point by point, the result health detection efficiency can be improved, the signal consistency is guaranteed, and the location precision can be improved.

Description

Spacecraft structure health detecting method based on sonic transducer

Technical field

The present invention relates to a kind of new spacecraft structure health detecting method, have simultaneously collision positioning, leakage positioning and The function of lesion assessment, belongs to structural health detection field.

Background technology

Due to spacecraft transmitting enter the orbit and running in by vibrated, vacuum, high/low temperature alternation, micrometeor and sky Between fragment, the interaction of elemental oxygen, solar radiation and cosmic ray, therefore, nacelle and sealing structure may produce loosening, become Shape, surface oxidation, burn into damage the even phenomenon such as perforation and then cause leakage accident, and this is by aerial mission and spacefarer Life security brings serious threat even to cause heavy consequence.

At present, spacecraft structure health detection has been done with certain research work both at home and abroad, developing has some special Equipment.Wherein, the U.S., Europe research work more deep, and domestic start late, technology is in urgent need to be improved.(1) NASA with A kind of supersonic leak detector of Si Chuan company of U.S. joint research and development (for example, see G.Studor, " Ultrasonic Detectors In Space, " in CTRL Systems, Inc., 2002, p.3 and A.Hoover, " Maryland Company Expanding Technology in Space-NASA Won't Leave Earth Without the CTRL UL101,"in CTRL Systems, Inc., 2002, p.1.), explored at suspicious position with ultrasonic detector, existed if there are leakage, ultrasonic Detector is able to detect that the ultrasonic wave that leakage produces, and sound that Ultrasonic transformation can be heard for human ear pass to earphone In, operator determines whether that by the sound in earphone leakage exists.(2) U.S. Invocon company developed in 2002 A kind of for fragment clash into detection and leak detection leak detection system (for example, see [3] Kevin D.Champaigne, Jonathan Sumners.Wireless impact and leak detection and location systems for the ISS and shuttle wing leading edge[C].IEEE Aerospace Conference Proceedings Proceedings.2005:1-7 and Kevin Champaigne and Eric Krug.Wireless Instrumentation System for Plasma Measurements on the International Space Station[C].AIAA Paper 2002-0937,AIAA Aerospace Sciences Meeting&Exhibit,40th, 2002), when spacecraft is when running into the urgent incident of leakage generation being caused by space debris and micrometeor shock, this system is not only Can detect because the sound of gas leakage generation, and triangulation can be carried out to leak position.(3) 2003 years, Europe NASA (ESA) utilizes embedded and surface-mount type fiber-optic grating sensor to carry out temperature on the spacecraft that repeatable transmitting utilizes With the monitoring structural health conditions verification experimental verification of strain (for example, see Martin A R, Fernando G F, Hale K F.Impact damage detection in filament wound tubes using embedded optical fiber sensors.Smart Materials and Structures).

In sum, the external method using has obvious limitation, first, these methods can only be implemented separately touching at present Hit positioning, leakage positioning or lesion assessment etc. it is impossible to realize above-mentioned functions simultaneously；Second, these methods or because poor sensitivity, Or because complex operation etc. is not all used widely.Therefore, a kind of new detecting method is badly in need of in this area, meets spacecraft knot The demand of structure health detection.

Content of the invention

It is an object of the invention to provide a kind of health detecting method of spacecraft structure, there is collision positioning, leakage is determined Position and the function of lesion assessment, are applicable to the detection of spacecraft in-orbit structural health, also applicable environment simulation facility, natural gas storage tank Deng the detection of tun structural health.

To achieve these goals, present invention employs following technical scheme：

A kind of spacecraft structure health detecting method, using two ultrasound array sensors, two multiple signals switch Occur to carry out with acquisition and analysis instrument with a signal, two ultrasound array sensors comprise respectively by same piezoelectric ceramics material 8 × 8 six ten four array elements that material makes, each array element includes two kinds of mode of operations and actively launches work and passively receive mould Formula, is fixed on spacecraft cabin inner surface, the switching of multiple signals switch PLC technology multiple signals, letter by couplant Number occur to be used for transmission signal excitation sonac gather sonac response signal with acquisition and analysis instrument, carry out letter Number process；Comprise the steps：

1) two ultrasound array sensors are fixed on spacecraft cabin inner surface by couplant, obtain array A and battle array Center distance L of row B, array element distance D, set up rectangular coordinate system, obtain the centre coordinate (x of array A₁, y₁), the center of array B Coordinate (x₂, y₂)；

2) any three array elements in sensor array A and array B are chosen, three array elements can not be real in same an array When detect the leakage acoustic emission signal that they receive, with the sample rate of more than the 3MB/s signal as 8KB for the acquisition length respectively, Its significant level is designated as U successively₁、U₂、U₃, take U=max (U₁,U₂,U₃), if three array elements are simultaneously received more than amplitude 10U Pulse signal, is judged as having collision or stress events to occur, now jumps to step 3)；If three array elements are simultaneously received amplitude More than 10U persistent signal, is judged as having incident of leakage to occur, now jumps to step 4)；If after detecting after a while, do not had Occur more than amplitude 10U signal when, then jump to step 5)；

3) signal amplitude of the array element that record above three is in passive reception pattern strengthened to moment during 10U respectively t₁、t₂、t₃If velocity of wave is v, calculates the position (x of collision or stress events according to following formula_I,y_I)

4) 64 array elements in array A are all set to passive reception pattern, 64 in synchronous acquisition array A The signal that array element receives, calculates directional angle θ to leakage sound source for the array A according to beamforming algorithm₁, in the same manner, will In array B, 64 array elements are all set to passive reception pattern, and in synchronous acquisition array B, 64 array element receives Signal, calculates directional angle θ to leakage sound source for the array B according to beamforming algorithm₂, leakage sound source is calculated according to following formula Position (x_L,y_L)；

5) by array B in the face of the row array unit of array A is all arranged to passive reception pattern, simultaneously by faced by array A The one row array unit of array B sets gradually into active emission mode, opens every time and actively launch mould in array B difference record array A The transmission signal of the array element of formula, records 8 times altogether, obtains signal virtual value saves as one 8 × 8 array, wherein, element U_ijGeneration In table array B, array element j receives the signal of array element i transmitting in array A, if there is an element U_mnValue be less than all units of matrix / 3rd of plain mean value, then it is assumed that having damage on line between array element m in array element n and array A in array B, otherwise do not have Damage and occur.

Wherein, array element distance D is less than 8mm.

Wherein, with the sample rate of more than the 10MB/s signal as 8KB for the acquisition length respectively.

Wherein, velocity of wave v determines according to Spacecraft Material.

Compared with prior art, it is an advantage of the current invention that：

1st, the present invention has collision positioning, leakage assessment and positioning, three kinds of functions of lesion assessment simultaneously.

2nd, ultrasound array sensor is directly pasted onto spacecraft module inner surface by the present invention, need not be to spacecraft cabin structure Make any change it is not required that astronaut operates to out of my cabin.

3rd, each array element of ultrasound array sensor used by the present invention is made it is ensured that believing by same piezoceramic material Number uniformity, improve positioning precision.

4th, the present invention can be to 4m around sensor²Scope realizes real-time monitoring it is not necessary to point by point scanning nacelle surface, improves The efficiency of spacecraft structure health detection.

Brief description

Fig. 1 is the structural representation of ultrasound array sensor used in the inventive method；

Fig. 2 is to pass through the method schematic diagram that two groups of acoustic emission sensor array obtain leakage sound source position in the present invention.

Fig. 3 is the flow chart of the spacecraft structure health detecting method of the present invention.

Specific embodiment

Introduced below is the specific embodiment as present invention, below by specific embodiment to the present invention Content further illustrates.Certainly, description following detailed description is only the content of the different aspect of the example present invention, and Should not be construed as limiting the invention scope.

When shock, leakage, injury event occur, section structure can produce acoustic emission signal due to stress, friction etc., should Acoustic emission signal is constantly propagated along wall.By each sensor synchronous acquisition acoustic emission signal of setting on spacecraft, Jing Guofang Big and filtering process, transfers signals in signal gathering analysis meter.Signal gathering analysis meter is processed to signal, sentences first Breaking and whether collide, if collide just positioning to collision point, starting leakage detection and localization module to leakage simultaneously Detected and positioned, subsequent start-up damage check module according to collision, leakage positioning result, to neighbouring structural damage degree Detected.

Based on such consideration, the present invention proposes following Space Vehicle Health detection method.

The in-orbit leak detection of new spacecraft of the present invention and small opening localization method, specific implementation step is as follows：

1st, two sensor arrays are fixed on spacecraft cabin inner surface, obtain center distance L of array A and array B, Array element distance D (less than 8mm), sets up rectangular coordinate system, obtains the centre coordinate (x of array A₁, y₁), the centre coordinate of array B (x₂, y₂)；

2nd, No. 1 array element of real time detecting sensor array A, No. 1 array element (any three of No. 64 array elements and sensor array B Individual it is impossible to choose in same an array) the leakage acoustic emission signal that receives, with the sample rate of 3MB/s (more than, 10MB/s) respectively Acquisition length is the signal of 8KB, and its significant level is designated as U successively₁、U₂、U₃, take U=max (U₁,U₂,U₃).If three array elements are same When receive the above pulse signal of amplitude 10U, be judged as having collision or stress events to occur, now jump to step 3；If three battle arrays Unit is simultaneously received the above persistent signal of amplitude 10U, is judged as having incident of leakage to occur, now jumps to step 4；

3rd, No. 1 array element of difference record array A, No. 1 array element of No. 64 array elements and sensor array B (is in passive reception Pattern) signal amplitude strengthens to moment t during 10U₁、t₂、t₃If velocity of wave is v, (according to known to Spacecraft Material can determine that V value), according to following formula calculate collision or stress events position (x_I,y_I)

4th, 64 array elements in array A are all set to passive reception pattern, 64 in synchronous acquisition array A The signal that array element receives, calculates directional angle θ to leakage sound source for the array A according to beamforming algorithm₁, in the same manner, will In array B, 64 array elements are all set to passive reception pattern, and in synchronous acquisition array B, 64 array element receives Signal, calculates directional angle θ to leakage sound source for the array B according to beamforming algorithm₂, leakage sound source is calculated according to following formula Position (x_L,y_L)；

5th, after detecting after a while, without occur more than amplitude 10U signal when, by array B in the face of array A A row array unit be all arranged to passive reception pattern, simultaneously by array A in the face of array B a row array unit set gradually into main Dynamic emission mode, opens the transmission signal of the array element of active emission mode every time, records 8 altogether in array B difference record array A Secondary, obtain signal virtual value saves as one 8 × 8 array., based in array A, 1-8 array element is changed successively taking Fig. 2 as a example Dynamic emission mode, the signal of the 1-8 array element receiving array A array element transmitting simultaneously of array B, signal virtual value is saved as one 8 × 8 array, wherein, element U_ijRepresent the signal that array element j in array B receives array element i transmitting in array A.If there being one Element U_mnValue be less than matrix all elements mean value 1/3rd then it is assumed that in array element n and array A in array B array element m it Between have damage on line, otherwise do not damage generation.

Although above the specific embodiment of the present invention being given with detailed description and illustrating, it should be noted that We can carry out various equivalent changes according to the conception of the present invention and change to above-mentioned embodiment, and function produced by it is made With still without departing from specification and accompanying drawing covered spiritual when, all should be within protection scope of the present invention.

Claims (3)

1. a kind of spacecraft structure health detecting method, using two ultrasound array sensors, two multiple signals switch and One signal occurs to carry out with acquisition and analysis instrument, and two ultrasound array sensors comprise respectively by same piezoceramic material 8 × 8 six ten four array elements making, each array element includes two kinds of mode of operations and actively launches work and passive reception pattern, Spacecraft cabin inner surface, the switching of multiple signals switch PLC technology multiple signals, signal are fixed on by couplant Occur to be used for transmission signal excitation sonac with acquisition and analysis instrument and gather sonac response signal, carry out signal Process；Comprise the steps：

1) two ultrasound array sensors are fixed on spacecraft cabin inner surface by couplant, obtain array A's and array B Center distance L, array element distance D, set up rectangular coordinate system, obtain the centre coordinate (x of array A₁, y₁), the centre coordinate of array B (x₂, y₂)；

2) any three array elements in sensor array A and array B are chosen, three array elements can not be examined in same an array in real time Survey the leakage acoustic emission signal that they receive, with the sample rate of more than the 3MB/s signal as 8KB for the acquisition length respectively, it has Effect level is designated as U successively₁、U₂、U₃, take U=max (U₁,U₂,U₃), if three array element is simultaneously received the pulse of more than amplitude 10U Signal, is judged as having collision or stress events to occur, now jumps to step 3)；If three array element be simultaneously received amplitude 10U with Upper persistent signal, is judged as having incident of leakage to occur, now jumps to step 4)；If after detecting after a while, do not gone out During more than existing amplitude 10U signal, then jump to step 5)；

3) signal amplitude of the array element that record above three is in passive reception pattern strengthens to moment t during 10U respectively₁、t₂、 t₃If velocity of wave is v, calculates the position (x of collision or stress events according to following formula_I,y_I)

$\left\{\begin{array}{c}\sqrt{{(x_I-x_{A1})}^2+{(y_I-y_{A1})}^2}-\sqrt{{(x_I-x_{A64})}^2+{(y_I-y_{A64})}^2}=(t_1-t_2)\&CenterDot;v\\ \sqrt{{(x_I-x_{A1})}^2+{(y_I-y_{A1})}^2}-\sqrt{{(x_I-x_{B1})}^2+{(y_I-y_{B1})}^2}=(t_1-t_3)\&CenterDot;v\end{array}\right.;$

4) 64 array elements in array A are all set to passive reception pattern, 64 array elements in synchronous acquisition array A The signal receiving, calculates directional angle θ to leakage sound source for the array A according to beamforming algorithm₁, in the same manner, by array B In 64 array elements be all set to passive reception pattern, the signal that in synchronous acquisition array B, 64 array element receives, Directional angle θ to leakage sound source for the array B is calculated according to beamforming algorithm₂, the position of leakage sound source is calculated according to following formula (x_L,y_L)；

$\left\{\begin{array}{c}{x}_L=x_1+\frac{{\mathrm{cot\&theta;}}_1\&times;L}{{\mathrm{cot\&theta;}}_1+{\mathrm{cot\&theta;}}_2}\\ y_L=y_1-\frac{L}{{\mathrm{cot\&theta;}}_1+{\mathrm{cot\&theta;}}_2}\end{array}\right.;$

5) by array B in the face of the row array unit of array A is all arranged to passive reception pattern, simultaneously by array A in the face of array B A row array unit set gradually into active emission mode, array B opens the battle array of active emission mode respectively in record array A every time The transmission signal of unit, records 8 times altogether, obtains signal virtual value saves as one 8 × 8 array, wherein, element U_ijRepresent array In B, array element j receives the signal of array element i transmitting in array A, if the value that there is an element Umn is less than matrix all elements putting down / 3rd of average, then it is assumed that having damage on line between array element m in array element n and array A in array B, otherwise do not damage Occur.

2. the method for claim 1, wherein array element distance D is less than 8mm.

3. the method for claim 1, wherein velocity of wave v determines according to Spacecraft Material.