Membrane structure tiny fragment detection method

Abstract

According to the membrane structure tiny fragment detection method, when tiny space fragments move at a high speed and impact a tensioned square membrane structure, vibration is generated on the membrane structure, the vibration is conducted to the four edges of the membrane structure through a thin film and collected by four metal resonance strips on the four edges, and piezoelectric thin films on the metal resonance strips are caused to vibrate; vibration signals are monitored through the piezoelectric film, four-side vibration signals are substituted into a rectangular film forced vibration equation, the position coordinates of a vibration source can be positioned, and the position of the vibration source is the fragment collision / breakdown position; through an upper layer of rectangular film and a lower layer of rectangular film which are arranged at a distance of 40cm, debris collision / breakdown positions of the micro space debris on two planes which are at a distance of 40cm can be obtained, and through a connecting line of the two positions, space moving track parameters, namely speed information, incident direction and angle information, of the micro space debris can be obtained. Wherein the film structure, the position of the metal resonance strip, the fine structure of the metal resonance strip and the position of the piezoelectric film are specially designed, so that the position of the metal resonance strip is located at the connection position of the tensioning structure of the film and the film, a microstructure resonance channel and a resonant cavity are engraved on the metal resonance strip, and the piezoelectric film is placed at the resonant cavity, so that the detection sensitivity is improved.

Description

Technical Field

[0001] The present invention relates to the field of tiny space debris detection, and in particular to an on-orbit passive ultra-high-speed tiny space debris sensing method using thin-film electrodes, which is used for on-orbit tiny space debris sensing and status monitoring of spacecraft. Background Art

[0002] With the increase of human activities in outer space, more and more space debris is left in the Earth's orbit. Spacecraft also face collisions with micrometeorites from comets and asteroid belts. These space debris and micrometeorites pose serious challenges to the safety of human space activities. The development and application of space debris / micrometeorite detection technology has been increasingly valued by various countries. As of the end of May 2020, there were more than 20,000 large debris (diameter greater than or equal to 10 cm) tracked and catalogued in low-Earth orbit, about 750,000 small debris (diameter between 1 and 10 cm), about 100 million tiny space debris of 1 to 10 mm, tens of billions of tiny space debris below 1 mm, and the number of tiny space debris less than 1 cm in size as high as 99.67% of the total.

[0003] The movement trajectory of large debris larger than 10 cm can be observed and predicted by ground-based equipment, and spacecraft can avoid them through active control, so the probability of large debris colliding with spacecraft is very low. Small debris between 1 and 10 cm and tiny space debris smaller than 1 cm are limited by the observation level and it is difficult to accurately determine the spatial distribution and detect them, so spacecraft cannot take effective active avoidance measures. Among them, tiny space debris has a very high probability of colliding with spacecraft due to its large number and wide distribution, posing a great threat to spacecraft in orbit, so it is also called "dangerous debris." For example, in 2011, the National Aeronautics and Space Administration (NASA) discovered 75 impact craters with diameters of 0.1 to 1.5 mm on the Multipurpose Service Module (MLM) of the International Space Station during maintenance; the fuel tank assembly (ATA) formed 49 impact craters with diameters of 0.1 to 1 mm; in 2021, NASA and the Canadian Space Agency discovered during a routine inspection of the International Space Station that there was a small hole with a diameter of 5 mm on the arm of the Canadarm2 robotic arm provided by Canada, which was caused by debris impact, but it is not known when the impact occurred.

[0004] In December 2022, the Soyuz MS-22 spacecraft collided with a 0.8mm tiny space debris / micrometeor and caused a cooling system failure. The impact point was not located until the 18th. Figure 1-2 As shown, a series of subsequent missions such as astronaut extravehicular activities and the return of American and Russian astronauts were forced to be canceled, and the Soyuz MS-23 will be used instead to replace the crew for return and evacuation.

[0005] In recent years, the failures caused by tiny space debris / micrometeoroids during the orbital operation of domestic and foreign spacecraft have begun to become prominent, seriously affecting the normal operation of spacecraft and becoming one of the main environmental safety threats faced by spacecraft. As an important milestone in China's space industry, the Chinese space station is expected to operate in orbit for more than 10 years in an increasingly harsh space environment after its on-orbit construction is completed. How to effectively sense the flux of tiny space debris in the orbit of the space station and the surrounding environment, establish a space debris orbit distribution model, and locate the impact point in a timely and accurate manner after a tiny space debris impact event occurs, so as to further evaluate the impact degree and facilitate on-orbit maintenance, is of great significance to ensuring the on-orbit safety of the space station.

[0006] At present, space debris detection is mainly divided into two categories, namely ground-based detection and space-based detection.

[0007] Telescopes and radars directly obtain orbital information of larger space debris. Due to technical limitations, ground-based equipment cannot capture tiny space debris. Space-based detection mainly uses radars, telescopes, sensors, etc. installed on spacecraft to detect space debris. Depending on whether the detector comes into contact with space debris, space-based detection can be divided into two categories. One is to install lasers, radars, cameras, etc. on the spacecraft to directly detect space debris; the other is to install sensors on the spacecraft to infer space debris information by detecting the relevant parameters when space debris collides with the spacecraft. Most of the detection of tiny space debris is carried out through the latter method. Using the detected space debris information, a space debris orbital distribution model can be established to provide relevant data for spacecraft structural protection design and debris avoidance.

[0008] At present, semiconductor detectors, ionization detectors, piezoelectric detectors, and combined detectors are mainly used to detect the collision kinetic energy of tiny space debris and the plasma after the collision. However, the sensor area of ​​these methods is relatively small and they do not have the ability to detect large areas. Summary of the invention

[0009] The purpose of the present invention is to overcome the shortcomings of the prior art and propose a method for detecting tiny debris with a membrane structure, so as to realize the detection of tiny space debris after impact and the detection of its motion trajectory, which can effectively enhance my country's ability to detect tiny space debris and achieve a dual improvement in scientific research and the safety assurance capability of spacecraft in orbit.

[0010] The basic principle of the present invention is: when tiny space debris collides with the tensioned square membrane structure at high speed, vibration is generated on the membrane structure, and the vibration is transmitted to the four sides of the membrane structure through the film, collected by the four metal resonance strips on the four sides, and causes the piezoelectric film on the metal resonance strip to vibrate. The vibration signal is monitored by the piezoelectric film, and the four-side vibration signal is brought into the rectangular membrane forced vibration equation, and the vibration source position coordinates can be located, and the vibration source position is the debris collision / breakdown position; through the upper and lower layers of rectangular membranes arranged 40 cm apart, the debris collision / breakdown position on two planes 40 cm apart can be obtained, and the space movement trajectory parameters of the tiny space debris, namely the speed information, incident direction, and angle information, can be obtained by connecting the two positions. The membrane structure, the metal resonance strip position, the metal resonance strip fine structure and the piezoelectric film position are specially designed, so that the metal resonance strip position is at the connection position between the tension structure of the membrane and the membrane, the metal resonance strip is engraved with a microstructure resonance channel and a resonance cavity, and the piezoelectric film is placed at the resonance cavity position to achieve improved detection sensitivity.

[0011] This method is achieved through the following technical solutions:

[0012] 1 This method arranges a compression tension structure at the edge of the film structure. The tension structure is in a compressed and tightened state in the launch section. After entering the track, the membrane structure is opened under the action of the ejection mechanism, and the compression tension structure is opened, so that the entire membrane structure is opened, and under the tensioning action of the tension structure, prestress is formed inside the membrane.

[0013] 2 The tension adjustment part of the compression tension structure is a butterfly spring composed of bimetallic strips. According to the change of membrane structure temperature, the expansion rate of the bimetallic strips is different, so that the bending degree of the tension adjustment part is different, thereby achieving different tensioning forces of membrane structures at different temperatures, keeping the membrane structure always in a tensioned state.

[0014] 3 Four metal resonance strips are placed on the four edges of the membrane structure, and the characteristic is that they are placed close to the edge of the membrane, one long side of the metal resonance strip is close to the tensioning structure, and the other long side is on the membrane.

[0015] 4 The metal resonance strip is a long and narrow strip, on which a resonance channel and a resonance cavity are processed by micromachining technology, and a piezoelectric film is set at the resonance cavity.

[0016] The piezoelectric film detects the vibration signal of the resonant cavity, and amplifies the charge signal of the piezoelectric film through a charge amplifier to obtain the amplified vibration signal.

[0017] 6 The time when the four charge amplifiers output piezoelectric signals is recorded as t1, t2, t3, and t4 respectively, and the time when the fragment reaches the membrane is set to t0. Then, the coordinate of the fragment impact position can be calculated based on the coordinate of the fragment impact position, the dimensional parameters of the membrane structure, the sound velocity of the membrane and t0, t1, t2, t3, and t4.

[0018] 7 Place the same membrane structure sensor in parallel at a distance of 40 cm from the membrane. The times when the four charge amplifiers of the membrane structure output piezoelectric signals are recorded as t1', t2', t3', and t4' respectively. Set the time when the debris reaches the membrane as t0'. Then, the debris impact position coordinate 2 can be calculated based on the debris impact position coordinate, the size parameters of the membrane structure, the sound velocity of the membrane and t0', t1', t2', t3', and t4'.

[0019] 8 The fragment velocity can be calculated based on the time t0 and t0' it takes for the fragment to pass through the two layers of film and the distance between the two layers of film.

[0020] 9 Based on the debris impact position coordinate 1 and the debris impact position coordinate 2, trajectory parameters such as the debris incident direction and angle can be calculated.

[0021] Compared with the prior art, the present invention has the following positive effects:

[0022] 1 The present invention proposes a method for detecting tiny fragments using a membrane structure, which can realize the detection of millimeter and sub-millimeter-level tiny particles.

[0023] 2 The present invention proposes a method for detecting tiny fragments of a membrane structure, which can realize detection in a larger range and provide information such as speed and angle.

[0024] 3 The present invention proposes a method for detecting tiny debris using a membrane structure, which can realize the detection of tiny space debris at the millimeter and sub-millimeter level. Compared with the existing technical means, it has a light structure, a large detection range, and can detect more parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0026] Figure 1 It is a schematic diagram of the principle of a method for detecting tiny fragments of a membrane structure.

[0027] Figure 2 It is a schematic diagram of the folding of a method for detecting tiny fragments of a membrane structure. DETAILED DESCRIPTION

[0028] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein, which are instead provided for a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not intended to limit the scope of protection of the present invention.

[0029] The technical solution of the present invention is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0030] Embodiment 1:

[0031] The present disclosure provides a method for detecting tiny fragments of a membrane structure, comprising:

[0032] 1See Figure 2 , Figure 2 As shown in a, this method sets a compressive tension structure at the edge of the film structure, and the tension structure in the emission section is Figure 2 b is the compressed and tightened state. After entering the track, the membrane structure opens under the action of the pop-up mechanism, and the compression tension structure opens, so that the entire membrane structure opens, and under the tensioning action of the tension structure, prestress is formed inside the membrane, wherein the pop-up mechanism opens the membrane structure along the rotation axis 3, and under the compression preload of the compression tension structure, the membrane structure opens along the rotation axis 2, and then opens along the rotation axis 3, and finally reaches Figure 2 a shows the expanded state.

[0033] 2 Figure 1 The tension adjustment part of the compression tension structure shown in the figure is a butterfly spring composed of bimetallic strips. Depending on whether the membrane structure is operating in a sunny area or a shaded area, and the change in the temperature of the membrane structure, the different expansion rates of the bimetallic strips can achieve different bending degrees of the tension adjustment part, thereby achieving different tensioning forces for membrane structures of different temperatures, keeping the membrane structure always in a tensioned state.

[0034] 3 Figure 1 Four metal resonance strips are placed on the four edges of the membrane structure shown in the figure. The characteristic of the metal resonance strips is that they are placed close to the edge of the membrane, one long side of the metal resonance strip is close to the tensioning structure, and the other long side is on the membrane.

[0035] 4 Figure 1 The metal resonance strip shown in the figure is a long and narrow strip, which is finely processed by micromachining technology to form a resonance channel and a resonance cavity, and a piezoelectric film is set at the resonance cavity.

[0036] 5The piezoelectric film detects the vibration signal of the resonant cavity and Figure 1 The charge amplifier shown in amplifies the charge signal of the piezoelectric film and obtains an amplified vibration signal.

[0037] 6 The time of the output piezoelectric signal of charge amplifier 1, charge amplifier 2, charge amplifier 3, and charge amplifier 4 is recorded as t1, t2, t3, and t4 respectively, and the time when the fragment reaches the membrane is set to t0. Then, according to the fragment impact position coordinates, the side length dimension parameter l of the membrane structure, the membrane sound velocity v and t0, t1, t2, t3, and t4, the fragment impact position coordinate 1 (x1, y1) can be calculated. Figure 1 A coordinate system is established on the membrane structure shown in the figure. The origin of the coordinate system is the lower left corner of the membrane, the positive direction of the x-axis is horizontal to the right, and the positive direction of the y-axis is vertically upward. The calculation formula is: x1 / (l-x1)=(t2-t0) / (t4-t0), y1 / (l-y1)=(t3-t0) / (t1-t0), and the sound velocity v of the membrane can be used to correct the deformation, l=v(t2+t4) or l=v(t3+t1).

[0038] 7 Place the same membrane structure sensor in parallel at a distance of 40 cm from the membrane. The times when the four charge amplifiers of the membrane structure output piezoelectric signals are recorded as t1', t2', t3', and t4' respectively. Set the time when the debris reaches the membrane as t0'. Then, the debris impact position coordinate 2 can be calculated based on the debris impact position coordinate, the size parameters of the membrane structure, the sound velocity of the membrane and t0', t1', t2', t3', and t4'.

[0039] 8 The fragment velocity can be calculated based on the time t0 and t0' it takes for the fragment to pass through the two layers of film and the distance between the two layers of film.

[0040] 9 Based on the debris impact position coordinate 1 and the debris impact position coordinate 2, trajectory parameters such as the debris incident direction and angle can be calculated.

Claims

1. A method for detecting tiny fragments of a membrane structure, characterized in that: The basic principle is: when tiny space debris collides with the tensioned square membrane structure at high speed, vibration is generated on the membrane structure, and the vibration is transmitted to the four sides of the membrane structure through the film, collected by the four metal resonance strips on the four sides, and causes the piezoelectric film on the metal resonance strip to vibrate. The vibration signal is monitored by the piezoelectric film, and the vibration signal of the four sides is brought into the forced vibration equation of the rectangular membrane, and the coordinates of the vibration source position can be located, which is the collision / breakdown position of the debris; through the upper and lower layers of rectangular membranes arranged 40 cm apart, the collision / breakdown position of the tiny space debris on two planes 40 cm apart can be obtained, and by connecting the two positions, the spatial trajectory parameters of the tiny space debris, namely the speed information, incident direction, and angle information, can be obtained. The membrane structure, the position of the metal resonance strip, the fine structure of the metal resonance strip, and the position of the piezoelectric film are specially designed, so that the metal resonance strip is located at the connection position between the tension structure of the membrane and the membrane, the metal resonance strip is engraved with a microstructure resonance channel and a resonance cavity, and the piezoelectric film is placed at the resonance cavity position to achieve improved detection sensitivity.

2. A method for detecting tiny fragments of a membrane structure, characterized in that: By setting a compression tension structure at the edge of the membrane structure, the tension structure is in a compressed and tightened state in the launch section. After entering the track, the membrane structure is opened under the action of the ejection mechanism, and the compression tension structure is opened, so that the entire membrane structure is opened, and under the tensioning action of the tension structure, prestress is formed inside the membrane. The tension adjustment part of the compression tension structure is a butterfly spring composed of bimetallic strips. According to the change of the membrane structure temperature, the expansion rate of the bimetallic strips is different, so that the bending degree of the tension adjustment part is different, thereby achieving different tensioning forces of membrane structures at different temperatures, and keeping the membrane structure always in a tensioned state. Four metal resonance strips are placed on the four edges of the membrane structure, and are characterized in that they are placed close to the edge of the membrane, one long side of the metal resonance strip is close to the tensioning structure, and one long side is on the membrane; The metal resonance strip is in the shape of a long and narrow strip, and is finely processed by micro-machining technology to form a resonance channel and a resonance cavity, and a piezoelectric film is arranged at the resonance cavity; The piezoelectric film detects the vibration signal of the resonant cavity, and amplifies the charge signal of the piezoelectric film through a charge amplifier to obtain the amplified vibration signal; The times of the output piezoelectric signals of the charge amplifier 1, charge amplifier 2, charge amplifier 3, and charge amplifier 4 are recorded as t1, t2, t3, and t4 respectively. The time when the fragments reach the membrane is set to t0. The fragment impact position coordinates 1 (x1, y1) can be calculated based on the fragment impact position coordinates, the side length dimension parameter l of the membrane structure, the membrane sound velocity v, and t0, t1, t2, t3, and t4. The calculation formula is x1 / (l-x1)=(t2-t0) / (t4-t0), y1 / (l-y1)=(t3-t0) / (t1-t0), and the membrane sound velocity v can be used to correct the deformation amount l, l=v(t2+t4) or l=v(t3+t1).

3. A method for detecting tiny fragments of a membrane structure, characterized in that: The same membrane structure sensor is placed parallel to the membrane at a distance of 40 cm. The times when the four charge amplifiers of the membrane structure output piezoelectric signals are recorded as t1', t2', t3', and t4' respectively. The time when the fragment reaches the membrane is set to t0'. The fragment impact position coordinate 2 can be calculated based on the fragment impact position coordinate, the size parameters of the membrane structure, the sound speed of the membrane and t0', t1', t2', t3', and t4'. The fragment speed can be calculated based on the time t0 and t0' when the fragment passes through the two layers of film and the distance between the two layers of film. The trajectory parameters such as the fragment incident direction and angle can be calculated based on the fragment impact position coordinate 1 and the fragment impact position coordinate 2.

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