A method and device for monitoring space debris impact in orbit based on PDV

Abstract

The application discloses a kind of based on PDV monitoring space's fragment impact in-orbit sensing method and device, solve the existing monitoring technology to be vulnerable to structure shape, temperature and complex electromagnetic environment influence, lead to the problem that cannot accurately obtain impact position and impact energy, specifically includes: multiple laser probes are arranged in the inside of cabin wall, to monitor the particle of cabin wall inner surface;When space debris impacts cabin wall, the particle of cabin wall inner surface generates disturbance, each laser probe emits laser to cabin wall inner surface, and receives the laser reflected by cabin wall inner surface to generate Doppler shift to obtain corresponding frequency signal, based on the time difference of signal of four measuring points that first appear frequency signal obtains the position coordinate of fragment impact point, the method and device can realize in-situ non-contact measurement, accurately obtain impact position, and not be influenced by structure shape, temperature and complex electromagnetic environment, the method provides reliable and accurate monitoring means for spacecraft in-orbit operation safety.

Description

Technical Field

[0001] This invention relates to on-orbit sensing methods and devices for spacecraft, specifically to an on-orbit sensing method and device for space debris impact based on PDV monitoring. Background Technology

[0002] As human activity in space increases, so does the amount of space debris, posing a serious threat to the operational safety of spacecraft. A typical spacecraft protective structure is the Whipple structure, consisting of two or three layers: an outer protective shield and an inner bulkhead. Typically, when space debris impacts at extremely high speeds and penetrates the protective shield, it creates a debris cloud. This cloud disperses and impacts the bulkhead, causing damage. The debris cloud may damage the bulkhead structure, and some larger debris clouds may even penetrate the bulkhead, injuring equipment and personnel inside the spacecraft. Therefore, monitoring technologies for impacts to spacecraft bulkheads are crucial for the safety of spacecraft in orbit. Current on-orbit sensing technologies primarily rely on acoustic emission, thermal measurement, thermal imaging, electromagnetic wave emission, accelerometers, and optical camera surface monitoring. These monitoring technologies are susceptible to the influence of structural shape, temperature, and complex electromagnetic environments. Summary of the Invention

[0003] The purpose of this invention is to provide an on-orbit sensing method and device for debris impact based on PDV monitoring space, in order to solve the technical problem that existing monitoring technologies are easily affected by structural shape, temperature and complex electromagnetic environment, resulting in the inability to accurately obtain the impact location and impact energy.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A method for on-orbit sensing of debris impacts based on PDV monitoring space is characterized by the following steps:

[0006] Step 1: Arrange multiple laser probes on the inner side of the bulkhead to monitor particles on the inner surface of the bulkhead. The multiple laser probes are arranged in an N×M matrix, where N×M≥4 and N and M are both positive integers. The distance between two adjacent laser probes in the horizontal and vertical directions is d.

[0007] Step 2: When space debris impacts the bulkhead, particles on the inner surface of the bulkhead are disturbed. Each laser probe emits laser light to the inner surface of the bulkhead and receives the laser light reflected from the inner surface of the bulkhead, generating a Doppler frequency shift to obtain the corresponding frequency signal. The first four frequency signals are acquired and converted into particle velocity-time history curves. The times when the corresponding particles are disturbed at the four measurement points are obtained from the particle velocity-time history curves as t1, t2, t3, and t4, where t1 > t2 > t4 > t3. At the same time, a coordinate system is established such that the coordinates of the four laser probes whose frequency signals appear first are (0, 2d), (d, 2d), (d, d), and (0, d), respectively. Among them, (0, 2d) corresponds to t1, (d, 2d) corresponds to t2, (d, d) corresponds to t3, and (0, d) corresponds to t4.

[0008] Step 3: Calculate the position coordinates (x, y) of the debris impact point:

[0009]

[0010]

[0011] in, D4 is the distance between the laser probe and the impact point corresponding to the coordinates (0, 2d), and c is the elastic wave velocity.

[0012] Furthermore, N = M = 3.

[0013] An on-orbit debris impact sensing device based on PDV monitoring space, used in the above-mentioned on-orbit debris impact sensing method based on PDV monitoring space, is characterized in that it includes N×M laser probes, probe fixing fixtures, N×M detectors, an oscilloscope and a computer, where N×M≥4 and N and M are both positive integers.

[0014] The probe fixing fixture is set on the inner side of the cabin wall. N×M laser probes are mounted on the probe fixing fixture and face the inner surface of the cabin wall, and are arranged in an N×M matrix. Each laser probe is connected to N×M detectors. Each detector is connected to the input terminal of the oscilloscope, and the output terminal of the oscilloscope is connected to the computer.

[0015] The laser probe is used to emit laser light to the inner surface of the bulkhead and receive the laser signal reflected by the inner surface of the bulkhead; the detector is used to detect the laser signal, the oscilloscope is used to acquire signal data, and the computer is used to record and process the signal data.

[0016] Furthermore, N = M = 3.

[0017] Furthermore, the probe fixing fixture is a fixed mounting plate;

[0018] The laser probe body is detachably connected to the fixed mounting plate, and its connecting wire passes through the fixed mounting plate to connect to the corresponding detector.

[0019] Furthermore, the laser probe is a narrow linewidth laser probe.

[0020] Furthermore, the laser probe is connected to the corresponding detector via an optical fiber.

[0021] The beneficial effects of this invention are:

[0022] 1. The present invention provides an on-orbit sensing device and method for debris impact monitoring based on PDV (Positioning Device and Vehicle) in space. It uses laser probes arranged on the inner surface of the spacecraft's cabin wall to monitor the particle velocity on the inner surface of the cabin wall. When a collision occurs, the impact point position can be calculated based on the time difference of the signals acquired by different laser probes. It can realize in-situ non-contact measurement, accurately obtain the impact position, and is not affected by structural shape, temperature and complex electromagnetic environment. This method provides a reliable and accurate monitoring means for the safe operation of spacecraft in orbit.

[0023] 2. The on-orbit sensing device and method for debris impact based on PDV monitoring space provided by this invention has a short response time, reaching the nanosecond level, and accurate signal interpretation.

[0024] 3. This invention uses a narrow linewidth laser probe, which is not easily damaged and can still be monitored after the tested material has delamination. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of an embodiment of an on-orbit sensing device for debris impact based on PDV monitoring space according to the present invention.

[0026] Figure 2 This is a schematic diagram of the coordinate system established in an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the conversion of frequency signals into particle velocity-time history curves in an embodiment of the present invention, wherein (a) is a frequency-time history curve and (b) is a particle velocity-time history curve.

[0028] Icon labels:

[0029] 1-Laser probe, 2-Probe fixing fixture, 3-Bulkhead. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] This invention provides an on-orbit sensing device for debris impact based on PDV monitoring space, such as... Figure 1 As shown, the system mainly includes a laser probe 1, a probe fixing fixture 2, an optical fiber, a detector, an oscilloscope, and a computer. The laser probe 1 emits and receives reflected laser light, the probe fixing fixture 2 fixes the position of the laser probe 1, the optical fiber transmits the laser signal, the detector detects the laser signal and converts it into an electrical signal, the oscilloscope acquires the raw signal data, and the computer records and processes the signal data.

[0032] When space debris impacts bulkhead 3, the resulting shock wave propagates along bulkhead 3. When the elastic precursor wave in the shock wave propagates to the inner surface of bulkhead 3, it disturbs the particles on the inner surface. At this time, laser probe 1 receives the reflected laser, which generates a Doppler frequency shift. The signal is transmitted back to the detector through an optical fiber and displayed on an oscilloscope. The frequency waveform in the oscilloscope is transmitted back to the computer, and through calculation, the frequency signals of the nine detectors can be obtained. Normally, only four signals are needed to determine the impact location of the debris. The arrangement of nine detectors is based on two considerations: (1) to consider design redundancy, so that there are still enough signals to determine the impact location when individual detectors fail; (2) nine detectors can make the determined location more accurate.

[0033] The interpretation method is based on the impact event description. For example... Figure 2 As shown, when the impact point occurs at the location shown in the diagram, let the coordinates of the impact point be (x, y). When the space debris impacts the bulkhead 3, measurement points ①-⑨ generate particle velocity signals respectively. Selecting the signals from the first four measurement points ①②⑤④, a coordinate system is established with their coordinates (0, 2d), (d, 2d), (d, d), and (0, d) respectively. A schematic diagram of the frequency signals is shown below. Figure 3 As shown in (a). The frequency signal obtained by the detector is converted into particle velocity, which can be obtained as follows. Figure 3particle velocity-time history curve shown in (b). D1 is the straight-line distance between measuring point ① and the impact point, the straight-line distance between measuring point ② and the impact point is D2, the straight-line distance between measuring point ⑤ and the impact point is D3, and the straight-line distance between measuring point ④ and the impact point is D4. The times when the frequency signal arrives at the four measuring points ⑤, ④, ②, ① sequentially are t3, t4, t2, t1 respectively, wherein (0, 2d) corresponds to t1, (d, 2d) corresponds to t2, (d, d) corresponds to t3, and (0, d) corresponds to t4; obviously D3<D4<D2<D1, thus t1>t2>t4>t3. Let the shortest time t3=0, it is speculated that the position (x,y) of the impact point has the following relationship with the time history curve:

[0034] x 2 +(y-2d) 2 =D1 2 ;

[0035] (x-d) 2 +(y-2d) 2 =D2 2 ;

[0036] (x-d) 2 +(y-d) 2 =D3 2 ;

[0037] x 2 +(y-d) 2 =D4 2 ;

[0038] D3-D4=c(t4-t3);

[0039] D2-D4=c(t2-t4);

[0040] D1-D2=c(t1-t2);

[0041] D1-D4=c(t1-t4);

[0042] The position (x, y) of the impact point is calculated from the above formulas:

[0043]

[0044]

[0045]

[0046] wherein c is the elastic wave velocity.

[0047] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present invention should be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An on-orbit sensing method for debris impact based on PDV monitoring space, characterized in that, Includes the following steps: Step 1: Arrange multiple laser probes (1) inside the bulkhead (3) to monitor particles on the inner surface of the bulkhead (3). The multiple laser probes (1) are arranged in an N×M matrix, where N×M≥4 and N and M are both positive integers. The distance between two adjacent laser probes (1) in the horizontal and vertical directions is d. Step 2: When space debris hits the bulkhead (3), the particles on the inner surface of the bulkhead (3) are disturbed. Each laser probe (1) emits laser to the inner surface of the bulkhead (3) and receives the laser reflected from the inner surface of the bulkhead (3) to generate Doppler frequency shift and obtain the corresponding frequency signal. The first four frequency signals are obtained and converted into particle velocity-time history curves. The time when the corresponding particles at the four measuring points are disturbed is obtained through the particle velocity-time history curves as t1, t2, t3 and t4, and t1 > t2 > t4 > t3. At the same time, a coordinate system is established so that the coordinates of the four laser probes (1) that first produce frequency signals are (0, 2d), (d, 2d), (d, d) and (0, d); where (0, 2d) corresponds to t1, (d, 2d) corresponds to t2, (d, d) corresponds to t3 and (0, d) corresponds to t4. Step 3: Calculate the position coordinates (x, y) of the debris impact point: ； ； in, D4 is the distance between the laser probe (1) and the impact point corresponding to the coordinate (0, 2d), and c is the elastic wave velocity.

2. The on-orbit sensing method for debris impact based on PDV monitoring space according to claim 1, characterized in that: N=M=3.

3. An on-orbit debris impact sensing device based on PDV monitoring space, used to implement the on-orbit debris impact sensing method based on PDV monitoring space as described in any one of claims 1-2, characterized in that: It includes N×M laser probes (1), probe fixing fixtures (2), N×M detectors, oscilloscopes and computers, where N×M≥4 and N and M are both positive integers; The probe fixing fixture (2) is set on the inner side of the bulkhead (3). N×M laser probes (1) are installed on the probe fixing fixture (2) and face the inner surface of the bulkhead (3), and are arranged in an N×M matrix. Each laser probe (1) is connected to N×M detectors in a one-to-one correspondence. Each detector is connected to the input terminal of the oscilloscope, and the output terminal of the oscilloscope is connected to the computer. The laser probe (1) is used to emit laser light to the inner surface of the bulkhead (3) and receive the laser signal reflected by the inner surface of the bulkhead (3); the detector is used to detect the laser signal, the oscilloscope is used to acquire signal data, and the computer is used to record and calculate the signal data.

4. The on-orbit sensing device for debris impact based on PDV monitoring space according to claim 3, characterized in that: N=M=3.

5. The on-orbit debris impact sensing device based on PDV monitoring space according to claim 3 or 4, characterized in that: The probe fixing fixture (2) is a fixing mounting plate; The laser probe (1) is detachably connected to the fixed mounting plate, and its connecting wire passes through the fixed mounting plate and is connected to the corresponding detector.

6. The on-orbit sensing device for debris impact based on PDV monitoring space according to claim 5, characterized in that: The laser probe (1) is a narrow linewidth laser probe.

7. The on-orbit sensing device for debris impact based on PDV monitoring space according to claim 6, characterized in that: The laser probe (1) is connected to the corresponding detector via an optical fiber.

Images