Automated monitoring system for Class V restricted sample return disposal devices

Abstract

The present invention discloses an automated monitoring system suitable for a Class V restricted sampling return disposal device, which relates to the field of planetary protection and can be used for the synchronous measurement of ambient temperature, ambient humidity, and concentrations of multiple gas components. It mainly includes a laser group for generating signal light of different wavelengths and its driver, a five-dimensional adjustment frame for adjusting the incident position and angle of the signal light, an embedded window in the sample processing cabin through which the signal light can pass, a multi-incident open-type stepped reflectivity optical multi-pass cell for multiple reflections of the signal light, and a detection signal processing module for detecting the output signal of the multi-incident open-type stepped reflectivity optical multi-pass cell. The present invention is not only suitable for the double-wall structure of an extraterrestrial sample processing cabin, which is convenient for adjustment and maintenance, but also can realize non-contact distributed high-precision synchronous monitoring of multiple environmental parameters.

Description

Technical Field

[0001] The present invention relates to the field of planetary protection, and in particular to an automated monitoring system suitable for a Class V restricted sampling return disposal device. Background Art

[0002] Planetary protection refers to the operation of avoiding cross-biological contamination between the Earth and extraterrestrial bodies when conducting deep space exploration. It generally includes two requirements: 1) Forward protection: protecting the natural state of the explored celestial body to avoid contamination of the exploration results and even affecting subsequent life exploration activities; 2) Return protection: preventing the Earth from being contaminated by materials from extraterrestrial bodies and ensuring that the Earth's biosphere is not contaminated or endangered by extraterrestrial life or materials. Implementing planetary protection in deep space exploration missions is both an inherent requirement for deep space exploration missions to achieve life detection and a recognized international responsibility and obligation. The specific requirements of the planetary protection policy requirements for unmanned deep space exploration missions are shown in Table 1.

[0003] Table 1 Current classification of international planetary protection needs

[0004]

[0005] With the continuous expansion of deep space exploration activities, in order to meet the needs of future sampling and return missions to extraterrestrial planets, the necessity of planetary protection is becoming increasingly prominent under the dual traction of scientific research needs and the safety needs of the Earth's ecosystem. However, at present, after the sealing devices of Class V restricted sampling and return are unsealed layer by layer, it is impossible to ensure that the contamination of extraterrestrial samples by Earth materials can be eliminated during the unsealing process, and it is also impossible to avoid the damage to the Earth's biosphere caused by potentially harmful organisms or substances in extraterrestrial samples. Therefore, it is urgent to realize the automated monitoring of Class V restricted sampling and return samples without direct contact by operators. Summary of the invention

[0006] In order to solve the technical problem that the environmental parameters such as humidity, temperature and oxygen content inside the double-walled processing cabin of the sampling return automated disposal device have different effects on extraterrestrial samples, thereby affecting the scientific nature of subsequent sample research and the technical problem that potential harmful organisms or substances in extraterrestrial samples may cause damage to the earth's biosphere, the present invention provides an automated monitoring system suitable for Class V restricted sampling return disposal devices, which can realize non-contact real-time measurement, ensure that the temperature, humidity and multi-gas component concentrations inside the double-walled processing cabin of the sampling return disposal device are monitored in real time and dynamically during the unsealing process of extraterrestrial samples, not only provide negative feedback input for the control system, but also can provide timely warning when the cabin environment is abnormal, ensure the safety and reliability of the extraterrestrial sample disposal process, and finally form effective scientific output. The present invention is not only suitable for the double-walled structure of the extraterrestrial sample processing cabin, which is convenient for adjustment and maintenance, but also can realize non-contact distributed high-precision synchronous monitoring of multiple environmental parameters.

[0007] In order to achieve the above object, the present invention adopts the following technical scheme:

[0008] An automated monitoring system suitable for a Class V restrictive sampling return disposal device comprises a laser driving module, a laser group, a five-dimensional adjustment frame group, an embedded window sheet of a sample processing chamber capable of transmitting signal light, a multi-incident open-type step reflectivity optical multi-pass cell for multiple reflections of the signal light, and a detection signal processing module; the laser driving module drives multiple laser groups to excite signal light of different wavelengths, and the signal light adjusts the incident position and the incident angle through the five-dimensional adjustment frame group, and the five-dimensional adjustment refers to the adjustment of the upper, lower, left, right and pitch angles; the signal light of different wavelengths is incident at different radii respectively, and forms a stable light field distribution through the multi-incident open-type step reflectivity optical multi-pass cell, so that the mirror surfaces of the relatively arranged first and second reflectors of the multi-incident open-type step reflectivity optical multi-pass cell present a multi-ring circular spot distribution of different radii, and then respectively emit from light outlets at different radii of the second reflector, and obtain the output signal of the multi-incident open-type step reflectivity optical multi-pass cell, and the detection signal processing module detects the output signal of the multi-incident open-type step reflectivity optical multi-pass cell.

[0009] Furthermore, the output wavelengths of the laser group are determined according to the absorption line positions of different types of gases to be measured, and the lasers of the laser group are all optical fiber outputs.

[0010] Furthermore, the embedded window of the sample processing chamber through which the signal light can pass includes a first window and a second window. The first window and the second window are both installed and embedded in the outer wall of the processing chamber, and both sides are coated with an anti-reflection film corresponding to the laser wavelength output by the laser group to reduce the intensity loss of the signal light during transmission.

[0011] Furthermore, the first reflector and the second reflector are both installed and embedded in the inner wall of the processing chamber with the reflective surface facing the inner side of the processing chamber, and the two are arranged opposite to each other, and the optical axes coincide with each other; the curvature radius of the reflective surface of the first reflector and the second reflector changes in a step-by-step manner, so that the reflective surfaces of different steps of the first reflector and the second reflector form a multi-ring circular spot distribution with different numbers of spot distributions, so as to ensure that signal lights of different wavelengths form the optimal number of spot distributions under the Herriott distribution on the reflective surfaces with different curvature radii.

[0012] Furthermore, the reflective surfaces of the first reflector and the second reflector are coated with a gold film except for the incident position and the exit position of the laser, and the incident position and the exit position are coated with an anti-reflection film of the target wavelength band;

[0013] Further, the surfaces of the first reflector and the second reflector facing the sandwich layer between the inner wall and the outer wall of the processing chamber are planes, and the annular steps of the surfaces facing the inner side of the processing chamber are concave surfaces; the single optical path length L between the first reflector and the second reflector is determined by the following formula:

[0014] The preset calculation formula is as follows:

[0015] ;

[0016] ;

[0017] ;

[0018] ;

[0019] ;

[0020] Wherein, k is the number of revolutions of the light beam around the optical axis of the first reflector or the second reflector to achieve re-incidence, and the number of revolutions of the light beam around the optical axis of the first reflector and the second reflector is equal, m is the number of light spots formed on the surface of the first reflector or the second reflector, and the number of light spots formed on the surfaces of the first reflector and the second reflector is equal, θ is the angle between adjacent light spots, r is the radius of curvature at the corresponding light spot distribution radius of the first reflector or the second reflector, and the radius of curvature of the first reflector and the second reflector are equal, x0 and y0 are the incident coordinate position of the signal light expressed with the center of the concave surface of the first reflector as the coordinate origin, x0' is the incident angle of the signal light, A is the distribution radius of the mirror light spot, the position of the anti-reflection film on the reflective surface of the first reflector and the second reflector is determined according to the distribution radius of the light spot, the radius of the anti-reflection film coating range is set to twice the diameter of the light spot of the incident signal light, and the single optical path length L satisfies 0 <L<2r。

[0021] Furthermore, the incident position of the signal light of the wavelength corresponding to the gas type with the highest detection sensitivity requirement is the outermost ring of the first reflector and the second reflector, and the incident position of the signal light of the wavelength corresponding to the gas type with the lower detection sensitivity requirement is closer to the inner ring of the first reflector and the second reflector.

[0022] Furthermore, the detection signal processing module includes a photoelectric detector, a signal acquisition unit and a processor corresponding to the emitted signal light, and reflects the oxygen concentration, carbon dioxide, ambient humidity and ambient temperature of the processing chamber.

[0023] Beneficial effects:

[0024] (1) The present invention can be well applied to the double-wall structure of the extraterrestrial sample processing cabin to form an integrated non-contact detection;

[0025] (2) The present invention does not require the placement of sensors in the cabin, thus greatly reducing the impact of the monitoring system on the environment inside the extraterrestrial sample processing cabin, while also improving the reliability of the sample handling process and meeting the isolation requirements between the inside and outside environments of the extraterrestrial sample processing cabin;

[0026] (3) The debugging and maintenance operations of the present invention do not need to be performed in the cabin, which makes the operation more convenient and effectively meets the requirements of a high-cleanliness internal environment of an extraterrestrial sample processing cabin;

[0027] (4) The present invention measures the average value of the environmental parameters along the path that the laser passes through. Compared with the traditional point measurement, the measurement result is more accurate, and the average measurement is more representative of the environmental parameters in the sample chamber;

[0028] (5) The present invention proposes a new type of multi-incident open-type stepped reflectivity optical multi-pass cell, which realizes the synchronous measurement of multiple environmental parameters of an extraterrestrial sample processing chamber in a limited spatial size, ensures the uniformity of the light spot distribution, and effectively suppresses the interference noise between the distributed light spots.

[0029] In summary, the present invention is based on spectroscopy technology and adopts a new open optical multi-pass cell to achieve high-precision monitoring of multiple environmental parameters in the processing cabin. Different from traditional sensors, the present invention is suitable for the double-wall structure of the extraterrestrial sample processing cabin, which is convenient for external adjustment and maintenance. In addition, compared with the contact measurement of traditional sensors, the present invention can achieve non-contact monitoring, avoiding the unreliable factors introduced by contact measurement in the cabin. In addition, compared with the single-parameter single-point measurement of traditional sensors, the present invention can achieve high-precision synchronous monitoring of distributed multiple environmental parameters, thereby more effectively ensuring the accuracy of monitoring environmental parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1An automated monitoring system for a Class V restricted sampling return disposal device provided in an embodiment of the present invention and a schematic diagram of its layout relative to a processing chamber (light propagation path is not shown);

[0031] Figure 2 A schematic cross-sectional view of an automated monitoring system for a Class V restricted sampling return disposal device and its layout relative to a processing chamber provided in an embodiment of the present invention (light propagation paths are not shown);

[0032] Figure 3 It is a schematic diagram of the structure of a multi-incident open-type stepped reflectivity optical multi-pass cell;

[0033] Figure 4 A schematic diagram of the simulation results of the spot distribution of a conventional Herriott optical multi-pass cell provided in an embodiment of the present invention;

[0034] Figure 5 A schematic diagram of the simulation results of the spot distribution of a multi-incident open-type stepped reflectivity optical multi-pass cell provided in an embodiment of the present invention;

[0035] Among them, the figure markings are: laser driving module 1, laser group 2, five-dimensional adjustment frame group 3, first window 4, first reflector 5, second reflector 6, second window 7, detection signal processing module 8, processing chamber outer wall 9, processing chamber inner wall 10, first support frame 11, second support frame 12, first radius range 51 of the first reflector, second radius range 52 of the first reflector, third radius range 53 of the first reflector, first radius range 61 of the second reflector, second radius range 62 of the second reflector, third radius range 63 of the second reflector. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0037] like Figure 1 , Figure 2 As shown, the automated monitoring system suitable for a Class V restrictive sampling return disposal device of the present invention includes a laser driving module 1, a laser group 2, a five-dimensional adjustment frame group 3, a first window 4, a first reflector 5, a second reflector 6, a second window 7, a detection signal processing module 8, an outer wall of a processing chamber 9, and an inner wall of a processing chamber 10.

[0038] The outer wall 9 of the processing chamber is provided with a laser driving module 1, a laser group 2, a first window 4, and a second window 7. The inner wall 10 of the processing chamber is provided with a first reflector 5 and a second reflector 6. The laser driving module 1 drives multiple laser groups 2 to excite signal lights of different wavelengths, and the signal lights are respectively emitted through three optical fibers, and the optical fiber head is installed on the five-dimensional adjustment frame group 3 to adjust the incident position and the incident angle, and the five dimensions refer to the adjustment of the upper, lower, left, right and pitch angles. The signal lights of different wavelengths are respectively incident at different radii, and after passing through the first window 4 and the first reflector 5, they go back and forth between the first reflector 5 and the second reflector 6, and a stable light field distribution is formed after one cycle, so that the mirror surfaces of the first reflector 5 and the second reflector 6 present a multi-ring circular spot distribution of different radii, and then they are respectively emitted from the light outlets at different radii of the second reflector 6, and after passing through the second window 7, the detection signal processing module 8 performs photoelectric conversion and signal processing, and finally inverts the oxygen concentration, carbon dioxide, ambient humidity and ambient temperature parameters of the processing chamber. The first window 4, the first reflector 5, the second reflector 6 and the second window 7 are coaxial. The five-dimensional adjustment frame assembly 3 and the detection signal processing module 8 are fixed on the first support frame 11 and the second support frame 12 respectively.

[0039] Preferably, both surfaces of the first window 4 and the second window 7 are coated with anti-reflection films of a wavelength corresponding to the laser group 2, so as to reduce signal light transmission loss and optical interference between mirror surfaces.

[0040] Preferably, the surface of the double-walled sandwich between the outer wall 9 and the inner wall 10 of the processing chamber of the first reflector 5 and the second reflector 6 is a plane, and is also coated with an anti-reflection film of the wavelength corresponding to the laser group 2. The reflective surfaces of the first reflector 5 and the second reflector 6 facing the inside of the processing chamber are coated with a gold film except for the incident position and the exit position. The incident position and the exit position are coated with an anti-reflection film of the wavelength corresponding to the laser group 2, and after forming a stable light field, the light spots formed by signal lights of different wavelengths have different reflectivities in the distributed ring, and the coating range is within a circular area centered on the incident point and the exit point. The diameter of the circular area is determined according to the set radius range. The light spot itself has a diameter, and the center point is variable. It is necessary to ensure that the light spot is maintained within the mirror radius range of the same curvature radius. The diameter of the circular area is preferably 8mm. Different incident positions and exit positions correspond to the distribution radius of the signal light spots of the corresponding wavelengths.

[0041] like Figure 3As shown, according to the "re-entrant" theory, that is, the theory of forming a single-circle spot distribution, the embodiment of the present invention performs three incidents, forming three circles of spot distribution at different radii of a light-pass pool, and the first reflector 5 and the second reflector 6 have different curvature radii at three different radii, achieving the purpose of multi-parameter simultaneous detection and ensuring the uniform distribution of the spots, thereby effectively suppressing the interference noise between the spots. Among them, the curvature radius at different radii of the concave surface of the first reflector 5 and the second reflector 6 in the optical multi-pass pool and the single optical path length L between the mirror surfaces can be set according to the number of mirror spot distribution requirements, as shown in the following formula:

[0042] ;

[0043] ;

[0044] ;

[0045] ;

[0046] Wherein, k is the number of revolutions of the light beam around the optical axis of the reflector to achieve single-cycle re-incidence, m is the number of light spots, θ is the angle between adjacent light spots, and r is the radius of curvature at the distribution radius of the high-reflection mirror light spot. x0 and y0 are the incident coordinate positions of the signal light expressed with the center of the concave surface of the first reflector 5 as the origin of the coordinates, A is the distribution radius of the mirror light spot, and the positions of the anti-reflection coatings on the reflective surfaces of the first reflector 5 and the second reflector 6 are determined according to the distribution radius of the light spots.

[0047] The incident angle x0' of the signal light can be obtained by the following formula:

[0048] ;

[0049] The width of the space enclosed by the inner wall 10 of the processing chamber is 2.5m, that is, the distance between the surface (reflection surface) of the first reflector 5 and the second reflector 6 facing the inner side of the processing chamber is also 2.5m. Assuming that the radius of the first reflector 5 and the second reflector 6 is 25mm, if the traditional Herriott multi-pass cell structure is used, only a single circle of incidence can be achieved. Taking a 20mm distribution radius as an example, 21 re-incidences can ensure uniform distribution of the light spot, and the effective absorption optical path is about 105m. However, in this case, only a single gas can be measured. The simulation results of the light spot distribution are shown in the figure. Figure 4As shown. Therefore, in order to achieve synchronous detection of multiple environmental parameters and multiple gases, the present invention proposes a new type of multi-incident open-type step reflectivity optical multi-pass cell. Taking the three-incident open-type step reflectivity new type optical multi-pass cell as an example, the radius of curvature of the annular area at the radius of 7.5mm to 12.5mm of the first reflector 5 and the second reflector 6 is 3781mm; the radius of curvature of the annular area at the radius of 12.5mm to 17.5mm of the first reflector 5 and the second reflector 6 is 2982mm; the radius of curvature of the annular area at the radius of 17.5mm to 22.5mm of the first reflector 5 and the second reflector 6 is 2799mm. The structure of the three-incident open-type step reflectivity new type optical multi-pass cell is as shown in FIG. Figure 3 As shown, the first reflector 5 has a first radius range 51 of the first reflector, a second radius range 52 of the first reflector, and a third radius range 53 of the first reflector, and the second reflector 6 has a first radius range 61 of the second reflector, a second radius range 62 of the second reflector, and a third radius range 63 of the second reflector. The spot distribution radius is 10mm, 15mm and 20mm respectively, and the number of re-incidences is 21 times, 16 times and 11 times respectively, corresponding to effective absorption optical paths of 105m, 80m and 55m. The simulation results of the spot distribution are shown in FIG. Figure 5 As shown. The three-circle spot distribution of triple incidence can respectively realize the measurement of oxygen, water vapor (ambient humidity) and carbon dioxide gas concentrations. By setting different curvature radii at different spot distribution radii, the uniform distribution of the spot is guaranteed, and the interference noise between the spots is effectively suppressed. When the absorption line strength of the selected gas is close, according to the detection sensitivity requirements, the outermost circle has the longest absorption optical path and is used for oxygen concentration measurement, the middle circle is used for water vapor concentration measurement, and the inner circle is used for the highest concentration of carbon dioxide gas measurement. It should be noted that, considering the need to monitor the internal ambient temperature of the cabin at the same time, when scanning the target absorption spectra of the three gases, at least one gas can realize the scanning of its double absorption lines, because the gas absorption line strength depends on temperature. Since different absorption lines have different low-state energy levels and different temperature dependence characteristics, two absorption lines of the same gas molecule can be selected and their line strength ratio can be used to measure temperature. It can be seen from the Beer-Lambert law that the line strength ratio is proportional to the ratio of the integral areas of the absorbance of the two absorption lines. In practical applications, the gas temperature can be inverted based on the integral area.

[0050] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. An automated monitoring system for a Class V restricted sampling return disposal device, characterized in that: The invention comprises a laser driving module, a laser group, a five-dimensional adjustment frame group, an embedded window piece of a sample processing cabin through which signal light can pass, a multi-incident open-type step reflectivity optical multi-pass cell for multiple reflections of signal light, and a detection signal processing module; the laser driving module drives multiple laser groups to excite signal light of different wavelengths, and the signal light adjusts the incident position and the incident angle through the five-dimensional adjustment frame group, and the five-dimensional adjustment refers to the adjustment of the upper, lower, left, right and pitch angles; the signal light of different wavelengths is incident at different radii respectively, and forms a stable light field distribution through the multi-incident open-type step reflectivity optical multi-pass cell, so that the mirror surfaces of the relatively arranged first reflector and the second reflector of the multi-incident open-type step reflectivity optical multi-pass cell present a multi-ring circular light spot distribution of different radii, and then respectively emit from the light outlets at different radii of the second reflector, and obtain the output signal of the multi-incident open-type step reflectivity optical multi-pass cell, and the detection signal processing module detects the output signal of the multi-incident open-type step reflectivity optical multi-pass cell.

2. An automated monitoring system for a Class V restricted sampling return disposal device according to claim 1, characterized in that: The output wavelength of the laser group is determined according to the absorption line positions of different types of gases to be measured, and the lasers of the laser group are all optical fiber outputs.

3. An automated monitoring system for a Class V restricted sampling return disposal device according to claim 1, characterized in that: The sample processing chamber embedded window that can transmit signal light includes a first window and a second window. The first window and the second window are both installed and embedded in the outer wall of the processing chamber and are arranged opposite to each other. Both sides of the first window and the second window are coated with an anti-reflection film corresponding to the laser wavelength output by the laser group.

4. The automated monitoring system for a Class V restricted sampling return disposal device according to claim 1, characterized in that: The first reflector and the second reflector are both installed and embedded in the inner wall of the processing chamber with the reflective surface facing the inner side of the processing chamber, and the two are arranged opposite to each other, and the optical axes coincide with each other; the curvature radius of the reflective surface of the first reflector and the second reflector changes in a step-by-step manner, so that the reflective surfaces of different steps of the first reflector and the second reflector form a multi-ring circular spot distribution with different numbers of spot distributions, so as to ensure that signal lights of different wavelengths form the optimal number of spot distributions under the Herriott distribution on the reflective surfaces with different curvature radii.

5. The automated monitoring system for a Class V restricted sampling return disposal device according to claim 1, characterized in that: The reflecting surfaces of the first reflector and the second reflector are all coated with gold film except for the incident position and the exit position of the laser, and the incident position and the exit position are all coated with anti-reflection film of the target band.

6. An automated monitoring system for a Class V restricted sampling return disposal device according to claim 4 or 5, characterized in that: The surfaces of the first reflector and the second reflector facing the sandwich layer between the inner wall and the outer wall of the processing chamber are planes, and the annular steps of the surfaces facing the inner side of the processing chamber are concave surfaces; the single optical path length L between the first reflector and the second reflector is determined by the following formula: The default calculation formula is as follows: ； ； ； ； ； Wherein, k is the number of revolutions of the light beam around the optical axis of the first reflector or the second reflector to achieve re-incidence, and the number of revolutions of the light beam around the optical axis of the first reflector and the second reflector is equal, m is the number of light spots formed on the surface of the first reflector or the second reflector, and the number of light spots formed on the surfaces of the first reflector and the second reflector is equal, θ is the angle between adjacent light spots, r is the radius of curvature at the corresponding light spot distribution radius of the first reflector or the second reflector, and the radius of curvature of the first reflector and the second reflector are equal, x0 and y0 are the incident coordinate position of the signal light expressed with the center of the concave surface of the first reflector as the coordinate origin, x0' is the incident angle of the signal light, A is the distribution radius of the mirror light spot, the position of the anti-reflection film on the reflective surface of the first reflector and the second reflector is determined according to the distribution radius of the light spot, the radius of the anti-reflection film coating range is set to twice the diameter of the light spot of the incident signal light, and the single optical path length L satisfies 0 <L<2r。 7. An automated monitoring system for a Class V restricted sampling return disposal device according to claim 6, characterized in that: The incident position of the signal light of the wavelength corresponding to the gas type with the highest detection sensitivity requirement is the outermost ring of the first reflector and the second reflector, and the incident position of the signal light of the wavelength corresponding to the gas type with the lower detection sensitivity requirement is closer to the inner ring of the first reflector and the second reflector.

8. An automated monitoring system for a Class V restricted sampling return disposal device according to claim 1, characterized in that: The detection signal processing module includes a photoelectric detector, a signal acquisition unit and a processor corresponding to the emitted signal light, and reflects the oxygen concentration, carbon dioxide, ambient humidity and ambient temperature of the processing chamber.

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